Today's Message Index:
----------------------
0. 12:32 AM - Value of the List... (Matt Dralle)
1. 03:50 AM - Re: Wing fitting / W.W. Corvair (DaveG601XL)
2. 04:02 AM - New baffles on the plane (Afterfxllc@aol.com)
3. 04:35 AM - Re: Zenith-List Digest: 14 Msgs - 11/23/08 (Don Baker)
4. 05:12 AM - Re: Spreading fear about the XL (jaybannist@cs.com)
5. 06:12 AM - Re: Spreading fear about the XL (Roger & Lina Hill)
6. 06:22 AM - Re: Spreading fear about the XL (LarryMcFarland)
7. 06:57 AM - Re: Spreading fear about the XL (steve)
8. 07:13 AM - Re: Spreading fear about the XL (Frank Roskind)
9. 07:44 AM - Re: Spreading fear about the XL (jaybannist@cs.com)
10. 07:46 AM - One more in the air (Dr. Andrew Elliott)
11. 07:52 AM - Re: One more in the air (Beckman, Rick)
12. 07:57 AM - Re: One more in the air ()
13. 07:57 AM - Re: Spreading fear about the XL (Dirk Zahtilla)
14. 08:00 AM - Re: One more in the air (DaveG601XL)
15. 08:16 AM - Re: Spreading fear about the XL (Dirk Zahtilla)
16. 09:11 AM - Re: One more in the air (Sabrina)
17. 09:47 AM - Re: Spreading fear about the XL (Rick Lindstrom)
18. 10:08 AM - Re: Spreading fear about the XL (japhillipsga@aol.com)
19. 10:33 AM - Re: Spreading fear about the XL (jaybannist@cs.com)
20. 11:18 AM - Chat Room Reminder (George Race)
21. 11:38 AM - Re: Spreading fear about the XL (steve)
22. 12:21 PM - Re: Spreading fear about the XL (Juan Vega)
23. 12:22 PM - Re: One more in the air (Juan Vega)
24. 01:26 PM - Re: Spreading fear about the XL (Clyde Barcus)
25. 03:52 PM - Re: One more in the air (Bill Naumuk)
26. 03:53 PM - Re: Spreading fear about the XL. (Gary Gower)
27. 03:58 PM - Re: One more in the air (leinad)
28. 04:03 PM - Re: One more in the air (Craig Payne)
29. 04:04 PM - Re: Spreading fear about the XL (Jay Maynard)
30. 04:07 PM - Re: One more in the air (Carlos Sa)
31. 04:11 PM - Re: One more in the air (Bill Naumuk)
32. 04:16 PM - 601XL passenger seat and baggage shelf dimensions? (Jay Maynard)
33. 04:23 PM - Re: One more in the air (n801bh@netzero.com)
34. 04:46 PM - Re: Spreading fear about the XL (JAPhillipsGA@aol.com)
35. 05:56 PM - Re: Spreading fear about the XL (Roger & Lina Hill)
36. 05:56 PM - Our 701 in the local AirShow. Flyers Guadalajara Vuela. (Gary Gower)
37. 06:58 PM - Re: Spreading fear about the XL (Rick Lindstrom)
38. 08:00 PM - Re: One more in the air (Ron Lendon)
39. 09:28 PM - My first week at FLAG (Richard Vetterli)
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| Subject: | Value of the List... |
If you look forward to checking your List email everyday (and a lot of you have
written to say that you do!), then you're probably getting at least $20 or $30
worth of Entertainment from the Lists each year. You'd pay twice that for a
subscription to some lame magazine or even just a single dinner out. Isn't the
List worth at least that much to you?
Won't you please take a minute to make your Contribution today and support the
Lists?
Contribution Page:
http://www.matronics.com/contribution
Again, I want to say THANK YOU to everyone that has made a Contribution thus far
during this year's List Fund Raiser!! These Lists are made possible exclusively
through YOUR generosity!!
Thank you for your support!
Matt Dralle
Email List Admin.
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| Subject: | Re: Wing fitting / W.W. Corvair |
Me too. My rear channel was very close to the 6-S-3 drop dimension from the longeron.
If you needed to move it a bit, there was some movement, but it was
not a lot.
Good luck,
--------
David Gallagher
601 XL/Jabiru 3300
First flight 7/24/08
Phase I flight test complete 10/16/08
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=216024#216024
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| Subject: | New baffles on the plane |
I went to the airport for a test fit of the new baffles.
**************One site has it all. Your email accounts, your social networks,
and the things you love. Try the new AOL.com
%26icid=aolcom40vanity%26ncid=emlcntaolcom00000001)
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| Subject: | Re: Zenith-List Digest: 14 Msgs - 11/23/08 |
PLEASE STOP SENDING US THIS KIND OF E-MAIL. We simply do not read it. Thank you.
>>> Zenith-List Digest Server <zenith-list@matronics.com> 11/24/08 2:21 AM >>>
*
=================================================
Online Versions of Today's List Digest Archive
=================================================
Today's complete Zenith-List Digest can also be found in either of the
two Web Links listed below. The .html file includes the Digest formatted
in HTML for viewing with a web browser and features Hyperlinked Indexes
and Message Navigation. The .txt file includes the plain ASCII version
of the Zenith-List Digest and can be viewed with a generic text editor
such as Notepad or with a web browser.
HTML Version:
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===============================================
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Zenith-List Digest Archive
---
Total Messages Posted Sun 11/23/08: 14
----------------------------------------------------------
Today's Message Index:
----------------------
1. 05:42 AM - Re: 9 Hour X-Country, engine purred, cables loosened! (ashontz)
2. 09:13 AM - Spreading fear about the XL (Jeff)
3. 09:28 AM - Re: Spreading fear about the XL (steve)
4. 01:18 PM - 601 XL Landing distance (Darryl Legg)
5. 02:34 PM - Re: 601 XL Landing distance (Juan Vega)
6. 02:45 PM - Re: 601 XL Landing distance (Bryan Martin)
7. 02:52 PM - Re: 601 XL Landing distance (Jay Maynard)
8. 03:39 PM - Re: Spreading fear about the XL (kmccune)
9. 05:49 PM - Re: Wing fitting / W.W. Corvair (John Smith)
10. 06:13 PM - Re: Wing fitting / W.W. Corvair (jaybannist@cs.com)
11. 06:52 PM - Re: Spreading fear about the XL (Roger & Lina Hill)
12. 07:10 PM - Re: Wing fitting / W.W. Corvair (dingfelder)
13. 07:32 PM - Re: Spreading fear about the XL (Bryan Martin)
14. 08:41 PM - Re: Spreading fear about the XL (Roger & Lina Hill)
________________________________ Message 1 _____________________________________
Time: 05:42:36 AM PST US
Subject: Zenith-List: Re: 9 Hour X-Country, engine purred, cables loosened!
From: "ashontz" <ashontz@nbme.org>
Excellent example. Same here. You have to pull on them pretty good too. And without
stretching them first they can become quite slack too.
Ron Lendon wrote:
> Scott,
>
> Great report.
>
> The only experience I have with keeping cables under consistent tension is my
guitar strings. I have been restringing guitars for many years and what I do
is bring them all in to tune then stretch them slightly by pulling them away
from the finger board. Then I re-tune and for the most part they stay in tune.
Experience has taught me that without the stretching step I chase the tune
of the guitar for about a week before it settles in. I would imagine this also
applies to cables but haven't found the documentation that states so.
>
> YMMV
--------
Andy Shontz
do not archive
CH601XL - Corvair
www.mykitlog.com/ashontz
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=215853#215853
________________________________ Message 2 _____________________________________
Time: 09:13:36 AM PST US
From: "Jeff " <jeffrey_davidson@earthlink.net>
Subject: Zenith-List: Spreading fear about the XL
Friends, neighbors, and fellow Zenith Enthusiasts,
I have received multiple off-list communications about the
unexplained XL crashes. We now have folks not part of the Zenith community
spreading "information" about the accidents. As I reported on this list
then, a group of LSA competitors advanced negative information about the XL
in person at the September 2007 Zenith Gathering in Winchester, Virginia.
For my part, I have not heard anything conclusive from the entities looking
at the design, including the Zenith Builder's Analysis Group, Zenith, the
NTSB, and European Governments, with two exceptions. One is the cable
tension advisory and the other is the European action. Neither tells us
what is happening unless you believe that insufficient cable tension is the
proper explanation. Others have failed to find any design problem despite
an extensive review. ZAC conducted a second static load test with
acceptable results. But the impact of all the discussion is becoming clear.
In the Second November Issue, 2008 of Trade-A-Plane, there are three kits
for sale and a completed aircraft. See page 87. Some advertisements have
appeared on this list. Locally, some builders are making the decision to
stop work on their projects. While all losses of human life are mourned
without reservation, especially losses that need not occur, I believe that
we all seek a rational explanation for these events if one exists, not
speculation about what the facts we know might mean.
So let me call on ZAC, the NTSB, the ZBAG, and all other
investigators with the standing to make valid conclusions, to report
whatever they have found or not found at this time in order to limit the
fear of the 601 XL that is currently spreading through the community. They
must speak up now before more damage based on fear is done to our community.
Please correct me if anyone with standing has provided a full
explanation of the events that are causing these concerns about the XL.
Jeff Davidson
________________________________ Message 3 _____________________________________
Time: 09:28:57 AM PST US
From: "steve" <notsew_evets@frontiernet.net>
Subject: Re: Zenith-List: Spreading fear about the XL
Jeff
Excellent response.
Im about to fly my 601XL and have concerns.
Steve W.
N 9554 Z
----- Original Message -----
From: Jeff
To: zenith-list@matronics.com
Sent: Sunday, November 23, 2008 10:12 AM
Subject: Zenith-List: Spreading fear about the XL
Friends, neighbors, and fellow Zenith Enthusiasts,
I have received multiple off-list communications about the
unexplained XL crashes. We now have folks not part of the Zenith
community spreading "information" about the accidents. As I reported on
this list then, a group of LSA competitors advanced negative information
about the XL in person at the September 2007 Zenith Gathering in
Winchester, Virginia. For my part, I have not heard anything conclusive
from the entities looking at the design, including the Zenith Builder's
Analysis Group, Zenith, the NTSB, and European Governments, with two
exceptions. One is the cable tension advisory and the other is the
European action. Neither tells us what is happening unless you believe
that insufficient cable tension is the proper explanation. Others have
failed to find any design problem despite an extensive review. ZAC
conducted a second static load test with acceptable results. But the
impact of all the discussion is becoming clear. In the Second November
Issue, 2008 of Trade-A-Plane, there are three kits for sale and a
completed aircraft. See page 87. Some advertisements have appeared on
this list. Locally, some builders are making the decision to stop work
on their projects. While all losses of human life are mourned without
reservation, especially losses that need not occur, I believe that we
all seek a rational explanation for these events if one exists, not
speculation about what the facts we know might mean.
So let me call on ZAC, the NTSB, the ZBAG, and all other
investigators with the standing to make valid conclusions, to report
whatever they have found or not found at this time in order to limit the
fear of the 601 XL that is currently spreading through the community.
They must speak up now before more damage based on fear is done to our
community.
Please correct me if anyone with standing has provided a
full explanation of the events that are causing these concerns about the
XL.
Jeff Davidson
________________________________ Message 4 _____________________________________
Time: 01:18:25 PM PST US
Subject: Zenith-List: 601 XL Landing distance
From: "Darryl Legg" <dlegg@tpg.com.au>
Hi pilots,
Just trying to get a real world idea of landing/take off distances required for
a 601 XL at sea level. ZAC states 500ft with a Jab engine, but is this really
conservative? Come on you bush pilots, can a landing/take off really be done
safely in a shorter distance?
Darryl.
do not archive
601 XL/Jabiru
getting there
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=215896#215896
________________________________ Message 5 _____________________________________
Time: 02:34:44 PM PST US
From: Juan Vega <amyvega2005@earthlink.net>
Subject: Re: Zenith-List: 601 XL Landing distance
200 ft does it for me, and i am at sea level, KSPG @ 8ft MSL.
51mph Vx, 70 Vy.
-----Original Message-----
>From: Darryl Legg <dlegg@tpg.com.au>
>Sent: Nov 23, 2008 4:17 PM
>To: zenith-list@matronics.com
>Subject: Zenith-List: 601 XL Landing distance
>
>
>Hi pilots,
>Just trying to get a real world idea of landing/take off distances required for
a 601 XL at sea level. ZAC states 500ft with a Jab engine, but is this really
conservative? Come on you bush pilots, can a landing/take off really be done
safely in a shorter distance?
>Darryl.
>do not archive
>601 XL/Jabiru
>getting there
>
>
>Read this topic online here:
>
>http://forums.matronics.com/viewtopic.php?p=215896#215896
>
>
________________________________ Message 6 _____________________________________
Time: 02:45:48 PM PST US
From: Bryan Martin <bryanmmartin@comcast.net>
Subject: Re: Zenith-List: 601 XL Landing distance
I wouldn't call 500 feet conservative for a 601XL. At gross weight and
no wind with standard sea level conditions, I'd call 500 feet of
runway the bare minimum. Under more favorable conditions, you can
probably get by with less. I would prefer to have at least 1000 feet
to work with, I doubt if I've ever used more than 1500.
On Nov 23, 2008, at 4:17 PM, Darryl Legg wrote:
>
> Hi pilots,
> Just trying to get a real world idea of landing/take off distances
> required for a 601 XL at sea level. ZAC states 500ft with a Jab
> engine, but is this really conservative? Come on you bush pilots,
> can a landing/take off really be done safely in a shorter distance?
> Darryl.
> do not archive
> 601 XL/Jabiru
> getting there
--
Bryan Martin
N61BM, CH 601 XL,
RAM Subaru, Stratus redrive.
do not archive.
________________________________ Message 7 _____________________________________
Time: 02:52:18 PM PST US
From: Jay Maynard <jmaynard@conmicro.com>
Subject: Re: Zenith-List: 601 XL Landing distance
On Sun, Nov 23, 2008 at 05:44:56PM -0500, Bryan Martin wrote:
> I wouldn't call 500 feet conservative for a 601XL. At gross weight and no
> wind with standard sea level conditions, I'd call 500 feet of runway the
> bare minimum. Under more favorable conditions, you can probably get by with
> less. I would prefer to have at least 1000 feet to work with, I doubt if
> I've ever used more than 1500.
I consider 1000 feet the minimum possible, and that's with maximum effort.
Anything under that is gravy. This goes double at max gross. It doesn't love
runways as much as, say, a Mooney, but do NOT underestimate the distance
required.
--
Jay Maynard, K5ZC, PP-ASEL http://www.conmicro.com
http://jmaynard.livejournal.com http://www.tronguy.net
Fairmont, MN (KFRM) (Yes, that's me!)
AMD Zodiac CH601XLi N55ZC http://www.tronguy.net/N55ZC.shtml
________________________________ Message 8 _____________________________________
Time: 03:39:15 PM PST US
Subject: Zenith-List: Re: Spreading fear about the XL
From: "kmccune" <kmccune@somtel.net>
The same guy has posted the following to 4 websites that I frequent. I posted
some comments about waiting for the out come and not jumping to conclusions, how
many hours that have been flown on this aircraft ect...
Here is the post.
" The CH601 XL apparently sports a failure mode that has caused one of its wings
to 'fold up' on at least seven occasions.
After such a case transpired in The Netherlands as well - killing both
occupants - the local authorities grounded all CH601 XL aircraft until
further notice."
It sound nice and is followed and ended with concern, but the exact same verb-age
was used in all the posts that I saw. Sounds a little fishy to me.
You most all, know that I'm not a 601 guy, but bad/misleading info just burns my
A$$.
I would fly in a Ch601 without any more care then getting in my truck... well depending
on the pilot. ;^)
In my opinion, that does not count for much in the big picture, the CH601 is an
excellent design and as safe as any. My gut tells me that the incidents were
caused by pilot error or extenuating circumstances, or both.
OK... back off my soap box. And just go fly your 601!
I'm still building my 701 so the jokes on me, anyway :^)
Kevin
--------
Mark Twain: Twenty years from now you will be more disappointed by the things that
you didn't do than by the ones you did do. So throw off the bowlines. Sail
away from the safe harbor. Catch the trade winds in your sails. Explore. Dream.
Discover.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=215904#215904
________________________________ Message 9 _____________________________________
Time: 05:49:22 PM PST US
From: John Smith <zenithlist@yahoo.com>
Subject: Re: Zenith-List: Wing fitting / W.W. Corvair
Do you remember how much vertical movement the rear spar can move relative
the rear spar attach plate?- My completed wings seem to be quite rigid at
the spars and I wonder if I can still adjust the wing pitch by moving rear
spar vertically when I bolt the wings.- Also, how do you measure the win
g pitch angle and at what location?=0A=0A=0A=0A=0A_________________________
_______=0AFrom: dingfelder <ding@tbscc.com>=0ATo: zenith-list@matronics.com
=0ASent: Saturday, November 22, 2008 1:50:05 PM=0ASubject: Re: Zenith-List:
Wing fitting / W.W. Corvair=0A=0A=0AWade,=0A----------
- Based on my experience, do NOT cut all the way back to the co-ordinates
shown in the plans. I would recommend leaving a minimum of 1/2 inch extra,
probably more, on your initial cut. Support your wing in some fashion, and
gradually mark and trim as you approach spar bolt alignment. Use the fusel
age side as a marker guide, mark, slide the wing out, trim and do it again
as you sneak up on the final position. If I recall correctly, the final gap
needs to be about 4mm for the rubber root moulding to fit well. Taper grou
nd 5/16" pins or hardware grade bolt shanks are ideal to help align the spa
r bolt holes as you get close. It took me about three or four hours to trim
each wing skin. Also, as part of this process, you need to-establish -
the rear spar final position vertically and laterally. Zenith wants a minim
um of 12mm edge distance (preferrably more)-on the rear spar bolt.-Use
a smaller bolt when-drilling the first hole, so you
still have room to tweak it.-Ideally, the centerline of the flap hinge p
in will align with the center-of the flap actuator shaft, though-"close
" is OK, as long as both sides are identically positioned relative to the f
uselage.=0A----------- On a separate note, I couldn't
be more satisfied with my W.W.-Corvair. The components that William prod
uces are first class in both design and manufacture, and-will-allow you
to produce a quality powerplant that performs exceptionally in the 601 / X
L. I'm still in early Phase one testing, and have no hard performance numbe
rs yet, but this plane-is all I hoped for, and more.-=0A--- -
-- --- --- --- --- --- --- --
- --- --- --- --- --- --- ---
--- --- --- --- --- --- --- -
-- --- --- --- --- --- Lynn Dingfelder=0A
--- --- --- --- --- --- --- -
-- --- --- --- --- --- --- --
- --- --- --- --- --- --- ---
--- --- --- --- --- --- --- 601 /
=========================0A
==================0A=0A=0A=0A
________________________________ Message 10 ____________________________________
Time: 06:13:17 PM PST US
Subject: Re: Zenith-List: Wing fitting / W.W. Corvair
From: jaybannist@cs.com
John,?
As I recall, my wings were fairly rigid in the wing pitch direction.? As it turned
out, that didn't make any difference, because they already conformed to the
pitch angle dimensions given on page 6-S-3 of the drawings, without any adjustment.?
I suppose you could move the rear spar up or down 1/4" or so, but not
much more than that.? If you have crossed your Ts and dotted your Is during construction,
I don't think you will have any problem.
Jay in Dallas
Do not archive
-----Original Message-----
From: John Smith <zenithlist@yahoo.com>
Sent: Sun, 23 Nov 2008 7:48 pm
Subject: Re: Zenith-List: Wing fitting / W.W. Corvair
Do you remember how much vertical movement the rear spar can move relative the
rear spar attach plate?? My completed wings seem to be quite rigid at the spars
and I wonder if I can still adjust the wing pitch by moving rear spar vertically
when I bolt the wings.? Also, how do you measure the wing pitch angle and
at what location?
________________________________________________________________________
Email message sent from CompuServe - visit us today at http://www.cs.com
________________________________ Message 11 ____________________________________
Time: 06:52:08 PM PST US
From: "Roger & Lina Hill" <hills@sunflower.com>
Subject: RE: Zenith-List: Spreading fear about the XL
Howdy all;
My A&P was looking over my 601HDS and commented that the ailerons were not
counterbalanced. He said this can lead to aileron flutter. My Sonerai had
balanced ailerons, can someone comment on if the 601XL has balanced ailerons
and if not, could this result in wing flutter?
Roger
_____
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of Jeff
Sent: Sunday, November 23, 2008 11:13 AM
Subject: Zenith-List: Spreading fear about the XL
Friends, neighbors, and fellow Zenith Enthusiasts,
I have received multiple off-list communications about the
unexplained XL crashes. We now have folks not part of the Zenith community
spreading "information" about the accidents. As I reported on this list
then, a group of LSA competitors advanced negative information about the XL
in person at the September 2007 Zenith Gathering in Winchester, Virginia.
For my part, I have not heard anything conclusive from the entities looking
at the design, including the Zenith Builder's Analysis Group, Zenith, the
NTSB, and European Governments, with two exceptions. One is the cable
tension advisory and the other is the European action. Neither tells us
what is happening unless you believe that insufficient cable tension is the
proper explanation. Others have failed to find any design problem despite
an extensive review. ZAC conducted a second static load test with
acceptable results. But the impact of all the discussion is becoming clear.
In the Second November Issue, 2008 of Trade-A-Plane, there are three kits
for sale and a completed aircraft. See page 87. Some advertisements have
appeared on this list. Locally, some builders are making the decision to
stop work on their projects. While all losses of human life are mourned
without reservation, especially losses that need not occur, I believe that
we all seek a rational explanation for these events if one exists, not
speculation about what the facts we know might mean.
So let me call on ZAC, the NTSB, the ZBAG, and all other
investigators with the standing to make valid conclusions, to report
whatever they have found or not found at this time in order to limit the
fear of the 601 XL that is currently spreading through the community. They
must speak up now before more damage based on fear is done to our community.
Please correct me if anyone with standing has provided a full
explanation of the events that are causing these concerns about the XL.
Jeff Davidson
________________________________ Message 12 ____________________________________
Time: 07:10:21 PM PST US
From: "dingfelder" <ding@tbscc.com>
Subject: Re: Zenith-List: Wing fitting / W.W. Corvair
John,
I concur with what Jay said. This was basically adjusted
when you used the "fixture" to set the relative spar locations.
Lynn Corry, PA
601 XL / Corvair
________________________________ Message 13 ____________________________________
Time: 07:32:01 PM PST US
From: Bryan Martin <bryanmmartin@comcast.net>
Subject: Re: Zenith-List: Spreading fear about the XL
The 601XL does not have balanced ailerons. If the control cables are
tensioned properly, this is not a problem. If the cables are way too
loose, there is a risk of flutter.
On Nov 23, 2008, at 9:50 PM, Roger & Lina Hill wrote:
> Howdy all;
>
> My A&P was looking over my 601HDS and commented that the ailerons
> were not counterbalanced. He said this can lead to aileron
> flutter. My Sonerai had
> balanced ailerons, can someone comment on if the 601XL has balanced
> ailerons and if not, could this result in wing flutter?
>
--
Bryan Martin
N61BM, CH 601 XL,
RAM Subaru, Stratus redrive.
do not archive.
________________________________ Message 14 ____________________________________
Time: 08:41:42 PM PST US
From: "Roger & Lina Hill" <hills@sunflower.com>
Subject: RE: Zenith-List: Spreading fear about the XL
Well, why not just add a counterbalance to the 601XL and get rid of the
flutter questions?
My sonerai had a simple method, it just had a weight ahead of the aileron
hinge at the wing tip. Though, this would mean having making a modification
to the wing tip. On the sonerai, it was a fiber glass wing tip so it was no
Problem adding it.
Roger
-----Original Message-----
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of Bryan Martin
Sent: Sunday, November 23, 2008 9:31 PM
Subject: Re: Zenith-List: Spreading fear about the XL
The 601XL does not have balanced ailerons. If the control cables are
tensioned properly, this is not a problem. If the cables are way too
loose, there is a risk of flutter.
On Nov 23, 2008, at 9:50 PM, Roger & Lina Hill wrote:
> Howdy all;
>
> My A&P was looking over my 601HDS and commented that the ailerons
> were not counterbalanced. He said this can lead to aileron
> flutter. My Sonerai had
> balanced ailerons, can someone comment on if the 601XL has balanced
> ailerons and if not, could this result in wing flutter?
>
--
Bryan Martin
N61BM, CH 601 XL,
RAM Subaru, Stratus redrive.
do not archive.
Message 4
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| Subject: | Re: Spreading fear about the XL |
Roger.?
Your A&P did not design the 601HDS.? How could he possibly know that "this could
lead to aileron flutter"?? Chris Heintz designed the CH200, CH601, CH601HD,
CH601HDS, CH601XL, CH701, CH801 and CH750, all without aileron balance. The rudder
and elevators are not balanced either. Control surface flutter is a MAJOR
concern of all aircraft designers. If he thought his control surface designs
could lead to flutter, don't you think he would have included some sort of balance?
Exactly how many of these designs (PROPERLY constructed, flown and maintained)
has experienced VERIFIED aileron flutter?
If you don't trust Chris Heintz, stay away from Chris Heinz designed airplanes.
Otherwise, COOL IT!
Jay in Dallas
Do not archive
-----Original Message-----
From: Roger & Lina Hill <hills@sunflower.com>
Sent: Sun, 23 Nov 2008 8:50 pm
Subject: RE: Zenith-List: Spreading fear about the XL
Howdy all;
?
My A&P was looking over my 601HDS and
commented that the ailerons were not counterbalanced.? He said this can
lead to aileron flutter.? My Sonerai had
balanced ailerons, can someone comment on
if the 601XL has balanced ailerons and if not, could this result in wing
flutter?
?
Roger
?
?
?
From:
owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of Jeff
Sent: Sunday, November 23, 2008
11:13 AM
Subject: Zenith-List: Spreading
fear about the XL
?
Friends, neighbors, and fellow Zenith Enthusiasts,
???????????
???????????
I have received multiple off-list communications about the unexplained XL
crashes.? We now have folks not part of the Zenith community spreading
"information" about the accidents.? As I reported on this list
then, a group of LSA competitors advanced negative information about the XL in
person at the September 2007 Zenith Gathering in Winchester, Virginia.?
For my part, I have not heard anything conclusive from the entities looking at
the design, including the Zenith Builder's Analysis Group, Zenith, the NTSB,
and European Governments, with two exceptions.? One is the cable tension
advisory and the other is the European action.? Neither tells us what is
happening unless you believe that insufficient cable tension is the proper
explanation.? Others have failed to find any design problem despite an
extensive review.? ZAC conducted a second static load test with acceptable
results.? But the impact of all the discussion is becoming clear.? In
the Second November Issue, 2008 of Trade-A-Plane, there are three kits for sale
and a completed aircraft.? See page 87. ?Some advertisements have
appeared on this list. ?Locally, some builders are making the decision to
stop work on their projects.? While all losses of human life are mourned
without reservation, especially losses that need not occur, I believe that we
all seek a rational explanation for these events if one exists, not speculation
about what the facts we know might mean.?
?
???????????
So let me call on ZAC, the NTSB, the ZBAG, and all other investigators with the
standing to make valid conclusions, to report whatever they have found or not
found at this time in order to limit the fear of the 601 XL that is currently
spreading through the community.? They must speak up now before more
damage based on fear is done to our community.
?
???????????
Please correct me if anyone with standing has provided a full explanation of
the events that are causing these concerns about the XL.
?
Jeff Davidson
?
?
? ??
?
?
http://www.matronics.com/contribution
http://www.matronics.com/contribution
________________________________________________________________________
Email message sent from CompuServe - visit us today at http://www.cs.com
Message 5
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| Subject: | Spreading fear about the XL |
Jay;
To be more exact, I believe his point was that ANY unbalanced aileron,
regardless of make and model, would be more likely to flutter and that
balancing them could reduce or even avoid the possibility of flutter. As
for not designing the 601, I don't think it is necessary to design something
in order to understand it. My A&P is about 70 years old, his dad was an A&P
as well, so I think he could know through a combination of training and
experience. He is also a homebuilder and so was his father, who
unfortunately died when his homebuilt wing failed in flight a few years ago.
Roger
_____
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of
jaybannist@cs.com
Sent: Monday, November 24, 2008 7:11 AM
Subject: Re: Zenith-List: Spreading fear about the XL
Roger.
Your A&P did not design the 601HDS. How could he possibly know that "this
could lead to aileron flutter"? Chris Heintz designed the CH200, CH601,
CH601HD, CH601HDS, CH601XL, CH701, CH801 and CH750, all without aileron
balance. The rudder and elevators are not balanced either. Control surface
flutter is a MAJOR concern of all aircraft designers. If he thought his
control surface designs could lead to flutter, don't you think he would have
included some sort of balance?
Exactly how many of these designs (PROPERLY constructed, flown and
maintained) has experienced VERIFIED aileron flutter?
If you don't trust Chris Heintz, stay away from Chris Heinz designed
airplanes. Otherwise, COOL IT!
Jay in Dallas
Do not archive
-----Original Message-----
From: Roger & Lina Hill <hills@sunflower.com>
Sent: Sun, 23 Nov 2008 8:50 pm
Subject: RE: Zenith-List: Spreading fear about the XL
Howdy all;
My A&P was looking over my 601HDS and commented that the ailerons were not
counterbalanced. He said this can lead to aileron flutter. My Sonerai had
balanced ailerons, can someone comment on if the 601XL has balanced ailerons
and if not, could this result in wing flutter?
Roger
_____
From: <mailto:owner-zenith-list-server@matronics.com>
owner-zenith-list-server@matronics.com [
<mailto:owner-zenith-list-server@matronics.com?>
mailto:owner-zenith-list-server@matronics.com] On Behalf Of Jeff
Sent: Sunday, November 23, 2008 11:13 AM
Subject: Zenith-List: Spreading fear about the XL
Friends, neighbors, and fellow Zenith Enthusiasts,
I have received multiple off-list communications about the
unexplained XL crashes. We now have folks not part of the Zenith community
spreading "information" about the accidents. As I reported on this list
then, a group of LSA competitors advanced negative information about the XL
in person at the September 2007 Zenith Gathering in Winchester, Virginia.
For my part, I have not heard anything conclusive from the entities looking
at the design, including the Zenith Builder's Analysis Group, Zenith, the
NTSB, and European Governments, with two exceptions. One is the cable
tension advisory and the other is the European action. Neither tells us
what is happening unless you believe that insufficient cable tension is the
proper explanation. Others have failed to find any design problem despite
an extensive review. ZAC conducted a second static load test with
acceptable results. But the impact of all the discussion is becoming clear.
In the Second November Issue, 2008 of Trade-A-Plane, there are three kits
for sale and a completed aircraft. See page 87. Some advertisements have
appeared on this list. Locally, some builders are making the decision to
stop work on their projects. While all losses of human life are mourned
without reservation, especially losses that need not occur, I believe that
we all seek a rational explanation for these events if one exists, not
speculation about what the facts we know might mean.
So let me call on ZAC, the NTSB, the ZBAG, and all other
investigators with the standing to make valid conclusions, to report
whatever they have found or not found at this time in order to limit the
fear of the 601 XL that is currently spreading through the community. They
must speak up now before more damage based on fear is done to our community.
Please correct me if anyone with standing has provided a full
explanation of the events that are causing these concerns about the XL.
Jeff Davidson
<http://www.matronics.com/contribution>
http://www.matronics.com/contribution
< pre>
_____
size=2 width="100%" align=center>
Email message sent from CompuServe - visit us today at <http://www.cs.com>
http://www.cs.com
http://www.matronics.com/contribution
http://www.matronics.com/Navigator?Zenith-List
Message 6
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| Subject: | Re: Spreading fear about the XL |
Hi Roger,
The HDS ailerons are not counterbalanced because the aircraft is not a
fast aircraft and the ailerons would have too low a frequency for flutter
unless you were in a high speed dive etc. I've no recollection that
anyone has reported flutter in the HDS 23-ft short thick wing.
I don't think cable tension or lack of it would affect the Zenith 601
series either.
Larry McFarland 601HDS at www.macsmachine.com
Roger & Lina Hill wrote:
>
> Howdy all;
>
>
>
> My A&P was looking over my 601HDS and commented that the ailerons were
> not counterbalanced. He said this can lead to aileron flutter. My
> Sonerai had
>
> balanced ailerons, can someone comment on if the 601XL has balanced
> ailerons and if not, could this result in wing flutter?
>
>
>
> Roger
>
>
>
Message 7
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| Subject: | Re: Spreading fear about the XL |
Piper J-3s, Piper Super Cubs never had counter balance weights. Built from
1938 til 1959 and now made by "other" names still dont use weights. Go
figure.....
SW
----- Original Message -----
From: "Roger & Lina Hill" <hills@sunflower.com>
Sent: Sunday, November 23, 2008 9:40 PM
Subject: RE: Zenith-List: Spreading fear about the XL
> <hills@sunflower.com>
>
>
> Well, why not just add a counterbalance to the 601XL and get rid of the
> flutter questions?
>
> My sonerai had a simple method, it just had a weight ahead of the aileron
> hinge at the wing tip. Though, this would mean having making a
> modification
> to the wing tip. On the sonerai, it was a fiber glass wing tip so it was
> no
> Problem adding it.
>
> Roger
>
>
> -----Original Message-----
> From: owner-zenith-list-server@matronics.com
> [mailto:owner-zenith-list-server@matronics.com] On Behalf Of Bryan Martin
> Sent: Sunday, November 23, 2008 9:31 PM
> To: zenith-list@matronics.com
> Subject: Re: Zenith-List: Spreading fear about the XL
>
>
> The 601XL does not have balanced ailerons. If the control cables are
> tensioned properly, this is not a problem. If the cables are way too
> loose, there is a risk of flutter.
>
> On Nov 23, 2008, at 9:50 PM, Roger & Lina Hill wrote:
>
>> Howdy all;
>>
>> My A&P was looking over my 601HDS and commented that the ailerons
>> were not counterbalanced. He said this can lead to aileron
>> flutter. My Sonerai had
>> balanced ailerons, can someone comment on if the 601XL has balanced
>> ailerons and if not, could this result in wing flutter?
>>
>
>
> --
> Bryan Martin
> N61BM, CH 601 XL,
> RAM Subaru, Stratus redrive.
> do not archive.
>
>
>
Message 8
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| Subject: | Spreading fear about the XL |
While I have trouble coming up with a slimier tactic than a competitor tras
hing Zenith over the difficulties=2C I also think that some people have ide
as which might be relevant to safety=2C not only of the XL=2C but even othe
r manufacturers' designs=2C whether or not they are XL builders. For all w
e know some of the competitors' designs have the same potential flaws as th
e XL=2C but just don't have enough exposure (they can't sell as many planes
) to have experienced an in-flight failure. In fact=2C if you go to earlie
r posts in this thread=2C you will read that the 70 year old A&P's father d
ied in a wing failure accident=2C which almost certainly did not involve a
601 XL. I would guess that anyone who lost his father in a wing failure ac
cident would take a very keen interest in the ways in which wings might fai
l=2C and would have some valuable contributions to make to the discussion.
I doubt that silencing opinions would have a beneficial effect=2C or would
lead to an end to XL wing failures. I think that balancing ailerons could
not hurt=2C nor could maintaining cable tension. Flutter might not be teh
accident cause=2C but it doesn't hurt to reduce the likelihood of flutter.
I also think that doing a good job of reaming holes on wing attach bolts
could not hurt either. I don't think that a wide range of thoughts on the
likey causes of the wing failures is harmful=2C as long as the discussion
does not blind us to other issues.
the XLDate: Mon=2C 24 Nov 2008 08:11:09 -0500From: jaybannist@cs.com
Roger. Your A&P did not design the 601HDS. How could he possibly know tha
t "this could lead to aileron flutter"? Chris Heintz designed the CH200=2C
CH601=2C CH601HD=2C CH601HDS=2C CH601XL=2C CH701=2C CH801 and CH750=2C all
without aileron balance. The rudder and elevators are not balanced either.
Control surface flutter is a MAJOR concern of all aircraft designers. If h
e thought his control surface designs could lead to flutter=2C don't you th
ink he would have included some sort of balance? Exactly how many of these
designs (PROPERLY constructed=2C flown and maintained) has experienced VERI
FIED aileron flutter?If you don't trust Chris Heintz=2C stay away from Chri
s Heinz designed airplanes. Otherwise=2C COOL IT!Jay in DallasDo not archiv
e
-----Original Message-----From: Roger & Lina Hill <hills@sunflower.com>To:
zenith-list@matronics.comSent: Sun=2C 23 Nov 2008 8:50 pmSubject: RE: Zenit
h-List: Spreading fear about the XL
Howdy all=3B
My A&P was looking over my 601HDS and commented that the ailerons were not
counterbalanced. He said this can lead to aileron flutter. My Sonerai had
balanced ailerons=2C can someone comment on if the 601XL has balanced ailer
ons and if not=2C could this result in wing flutter?
Roger
From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-serv
er@matronics.com] On Behalf Of Jeff Sent: Sunday=2C November 23=2C 2008 11:
13 AMTo: zenith-list@matronics.comSubject: Zenith-List: Spreading fear abou
t the XL
Friends=2C neighbors=2C and fellow Zenith Enthusiasts=2C
I have received multiple off-list communications about the unex
plained XL crashes. We now have folks not part of the Zenith community spr
eading "information" about the accidents. As I reported on this list then
=2C a group of LSA competitors advanced negative information about the XL i
n person at the September 2007 Zenith Gathering in Winchester=2C Virginia.
For my part=2C I have not heard anything conclusive from the entities look
ing at the design=2C including the Zenith Builder's Analysis Group=2C Zenit
h=2C the NTSB=2C and European Governments=2C with two exceptions. One is t
he cable tension advisory and the other is the European action. Neither te
lls us what is happening unless you believe that insufficient cable tension
is the proper explanation. Others have failed to find any design problem
despite an extensive review. ZAC conducted a second static load test with
acceptable results. But the impact of all the discussion is becoming clear
. In the Second November Issue=2C 2008 of Trade-A-Plane=2C there are three
kits for sale and a completed aircraft. See page 87. Some advertisements
have appeared on this list. Locally=2C some builders are making the decis
ion to stop work on their projects. While all losses of human life are mou
rned without reservation=2C especially losses that need not occur=2C I beli
eve that we all seek a rational explanation for these events if one exists
=2C not speculation about what the facts we know might mean.
So let me call on ZAC=2C the NTSB=2C the ZBAG=2C and all other
investigators with the standing to make valid conclusions=2C to report what
ever they have found or not found at this time in order to limit the fear o
f the 601 XL that is currently spreading through the community. They must
speak up now before more damage based on fear is done to our community.
Please correct me if anyone with standing has provided a full e
xplanation of the events that are causing these concerns about the XL.
Jeff Davidson
http://www.matronics.com/contribution< pre>
Email message sent from CompuServe - visit us today at http://www.cs.com
_________________________________________________________________
Proud to be a PC? Show the world. Download the =93I=92m a PC=94 Messenger t
hemepack now.
Message 9
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|
| Subject: | Re: Spreading fear about the XL |
Roger,
Not to be argumentative, but I am 74 years old and I practiced architecture
for more than 45 years. So I know a LOT about building design.=C2- That do
es not qualify me to judge the functional or structural integrity of another
architect's design without knowing the details of the criteria,=C2- the s
pecific goals for the design, and the logic of the design solution.=C2- I
have plenty of prejudices when it comes to the practice of architecture; but
I recognize them a such and refrain from publicly condemning others who do
not share my philosophy. =C2-
Stating that "ANY unbalanced aileron, regardless of make and model, =C2-wo
uld be more
likely to flutter and that balancing them could reduce or even avoid =C2-t
he
possibility of flutter" is a prejudiced statement and it is simply not true.
=C2- Flutter potential of any control surface is determined by the totalit
y of the design: size, shape, weight, weight distribution, pivot location, c
ontrol system, design speed and so forth and so on.=C2- If the designer ma
kes the right choices (which might compromise other parts of the design) he
can provide a control surface that will not flutter, period. However, many e
xamples prove that most designers are not willing to compromise other parts
of the airframe to provide a flutter-free control surface.=C2- The fallbac
k is to provide a design work-around in the form of balance weights or aerod
ynamic balancing surfaces. That is not to criticize the use of balancing.
=C2- It is simply a matter of choice.=2
0Chris Heintz chose to provide control surfaces that do not need balancing w
hen operated within the stated operating limits.=C2- If you exceed those l
imits, you are on your own and in dangerous territory - "outside the envelop
e".=C2- That is true of any aircraft and it is where failures occur, inclu
ding control surface flutter, wing failure and who knows what.=C2-
I'll say it again:=C2- If you don't trust the designer, don't fly the airp
lanes he has designed.=C2- And don't try to "tweek" his design when you do
n't know why and how it was designed the way it is.
'Nuff said - Jay in Dallas
Do not archive
-----Original Message-----
From: Roger & Lina Hill <hills@sunflower.com>
Sent: Mon, 24 Nov 2008 8:11 am
Subject: RE: Zenith-List: Spreading fear about the XL
=C2-
Jay;
=C2-
To be more exact, I believe his point was
that ANY unbalanced aileron, regardless of make and model, =C2-would be mo
re
likely to flutter and that balancing them could reduce or even avoid =C2-t
he
possibility of flutter.=C2- As for not designing the 601, I don=99t
think
it is necessary to design something in order to understand it. My A&P is
about 70 years old, his dad was an A&P as well, so I think he could know
through a combination of training and experience. He is also a homebuilder a
nd
so was his father, who unfortunately died when his homeb
uilt wing failed in
flight a few years ago.
=C2-
Roger
=C2-
=C2-
=C2-
From:
owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matr
onics.com]
On Behalf Of
jaybannist@cs.com
Sent: Monday, November 24, 2008
7:11 AM
Subject: Re: Zenith-List:
Spreading fear about the XL
=C2-
Roger.=C2-
Your A&P did not design the 601HDS.=C2- How could he possibly know that
"this could lead to aileron flutter"?=C2- Chris Heintz designed the
CH200, CH601, CH601HD, CH601HDS, CH601XL, CH701, CH801 and CH750, all withou
t
aileron balance. The rudder and elevators are not balanced either. Control
surface flutter is a MAJOR concern of all aircraft designers. If he thought
his
control surface designs could lead to flutter, don't you think he would have
included some sort of balance?
Exactly how many of these designs (PROPERLY constructed, flown and maintaine
d)
has experienced VERIFIED aileron flutter?
If you don't trust Chris Heintz, stay away from Chris Heinz designed airplan
es.
Otherwise, COOL IT!
Jay in Dallas
Do not archive
=C2-
=C2-
-----Original
Message-----
From: Roger & Lina Hill <hills@sunflower.com>
Sent: Sun, 23 Nov 2008 8:50 pm
Subject: RE: Zenith-List: Spreading fear about the XL
Howdy all;
=C2-
My A&P was=2
0looking over my 601HDS and
commented that the ailerons were not counterbalanced.=C2- He said this can
lead to aileron flutter.=C2- My Sonerai had
balanced ailerons, can someone comment on
if the 601XL has balanced ailerons and if not, could this result in wing
flutter?
=C2-
Roger
=C2-
=C2-
=C2-
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com]
On Behalf Of
Jeff
Sent: Sunday, November 23, 2008
11:13 AM
Subject: Zenith-List: Spreading
fear about the XL
=C2-
Friends, neighbors, and fellow Zenith Enthusiasts,
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-
I have received multiple off-list communications about the unexplained XL
crashes.=C2- We now have folks not part of the Zenith community spreading
"information" about the accidents.=C2- As I reported on this list
then, a group of LSA competitors advanced negative information about the XL
in
person at the September 2007 Zenith Gathering in Winchester, Virginia.=C2
-
For my part, I have not heard anything conclusive from the entities looking
at
the design, including the Zenith Builder's Analysis Group, Zenith, the NTSB,
and European Governments, with two exceptions.=C2- One is the cable tensio
n
ad
visory and the other is the European action.=C2- Neither tells us what is
happening unless you believe that insufficient cable tension is the proper
explanation.=C2- Others have failed to find any design problem despite an
extensive review.=C2- ZAC conducted a second static load test with accepta
ble
results.=C2- But the impact of all the discussion is becoming clear.=C2
- In
the Second November Issue, 2008 of Trade-A-Plane, there are three kits for s
ale
and a completed aircraft.=C2- See page 87. =C2-Some advertisements have
appeared on this list. =C2-Locally, some builders are making the decision
to
stop work on their projects.=C2- While all losses of human life are mourne
d
without reservation, especially losses that need not occur, I believe that w
e
all seek a rational explanation for these events if one exists, not speculat
ion
about what the facts we know might mean.=C2-
=C2-
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-
So let me call on ZAC, the NTSB, the ZBAG, and all other investigators with
the
standing to make valid conclusions, to report whatever they have found or no
t
found at this time in order to limit the fear of the 601 XL that is currentl
y
spreading through the community.=C2- They must speak up now before more
damage based on fear is done to our community.
=C2-
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-
Please correct me if anyone with standing has provided a full explanation of
the=2
0events that are causing these concerns about the XL.
=C2-
Jeff Davidson
=C2-
=C2-
=C2- =C2-=C2-
=C2-
=C2-
http://www.matronics.com/contribution
< pre>
size=2 width="100%" align=center>
Email message sent from CompuServe - visit us today at
http://www.cs.com
=C2-
=C2-
http://www.matronics.com/contribution
http://www.matronics.com/Navigator?Zenith-List
http://forums.matronics.com
th-List Email Forum -
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Message 10
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| Subject: | One more in the air |
Gang:
I am happy to report that N601GE, a Zodiac 601XL/TD, powered by a 3100
Corvair, took to the skies this morning for the first time at KFFZ,
Mesa, AZ. 0.7 hours, no engine problems.
Horizontal stabilizer likely needs some incidence adjustment, as full
aft trim was needed at 100 MIAS and left arm below that. Otherwise no
airframe problems.
More to report as flight testing continues...
Andy Elliott, Mesa, AZ
Message 11
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| Subject: | One more in the air |
Way to go, Doc!!!!!
Rick
Do not archive
Gang:
I am happy to report that N601GE, a Zodiac 601XL/TD, powered by a 3100
Corvair, took to the skies this morning for the first time at KFFZ,
Mesa, AZ. 0.7 hours, no engine problems.
Horizontal stabilizer likely needs some incidence adjustment, as full
aft trim was needed at 100 MIAS and left arm below that. Otherwise no
airframe problems.
More to report as flight testing continues...
Andy Elliott, Mesa, AZ
Message 12
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| Subject: | Re: One more in the air |
Congrats!!! What a Thanksgiving gift.
Jerry
CHD arizona
---- "Dr. Andrew Elliott" <a.s.elliott@cox.net> wrote:
> Gang:
>
> I am happy to report that N601GE, a Zodiac 601XL/TD, powered by a 3100 Corvair,
took to the skies this morning for the first time at KFFZ, Mesa, AZ. 0.7 hours,
no engine problems.
>
> Horizontal stabilizer likely needs some incidence adjustment, as full aft trim
was needed at 100 MIAS and left arm below that. Otherwise no airframe problems.
>
> More to report as flight testing continues...
>
> Andy Elliott, Mesa, AZ
Message 13
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| Subject: | Re: Spreading fear about the XL |
You forgot the 640 which also has unbalanced ailerons HOWEVER... it has
push-pull tubes instead of cables and boxed wing spars (more related to
the load carying capacity).The margin between cruise and VNE is much
closer than the XL design. Maybe we need to look at this!? As I look at
the designs, they become capable of increasingly high cruise speeds and
with builders putting more h.p. in it becomes very easy to reach VNE
very quickly by entering even a very shallow dive. (also the rudder on
the 6,7,&8 series ARE balanced, note the portion of the rudder ahead of
the hinge points...this is aerodynamic balance as opposed to weight
balance).
I think that what we are seeing is two groups of builders here: one
group who builds and fly's well within the specs of the design, and one
group that wants to achieve everything to the edge of the envelope and
perhaps a bit beyond. One group is made of builder/flyers, and one group
is made of experimenter builders/test pilots. This latter group will
always push aircraft design firms to re-examine their designs and
hopefully this will benefit the first group who will end up flying
increasingly safe and more capable aircraft.
I'm sure that no-one on this list means to offend the builder/flyer
group, I know I don't. We are just part of the group that reaches out to
extend our potential.
I am building a 601XL (which I may re-designate as
601XLA(airobat)orM(modified) just to make it clear that it is not
totally to plans) As I have said before I will use push-pull tubes for
the ailerons and elevator and balance both as well. The ailerons will
move the hingepoint rearward and the elevator will use weights in the
tips which will be attached to the elevator instead of the horizontal
stab. I will also use a boxed spar in the wing that meets at the center
instead of bolting on at the outer part of the fuselage.
Dirk Z
----- Original Message -----
From: jaybannist@cs.com
To: zenith-list@matronics.com
Sent: Monday, November 24, 2008 5:11 AM
Subject: Re: Zenith-List: Spreading fear about the XL
Roger.
Your A&P did not design the 601HDS. How could he possibly know that
"this could lead to aileron flutter"? Chris Heintz designed the CH200,
CH601, CH601HD, CH601HDS, CH601XL, CH701, CH801 and CH750, all without
aileron balance. The rudder and elevators are not balanced either.
Control surface flutter is a MAJOR concern of all aircraft designers. If
he thought his control surface designs could lead to flutter, don't you
think he would have included some sort of balance?
Exactly how many of these designs (PROPERLY constructed, flown and
maintained) has experienced VERIFIED aileron flutter?
If you don't trust Chris Heintz, stay away from Chris Heinz designed
airplanes. Otherwise, COOL IT!
Jay in Dallas
Do not archive
-----Original Message-----
From: Roger & Lina Hill <hills@sunflower.com>
To: zenith-list@matronics.com
Sent: Sun, 23 Nov 2008 8:50 pm
Subject: RE: Zenith-List: Spreading fear about the XL
Howdy all;
My A&P was looking over my 601HDS and commented that the ailerons were
not counterbalanced. He said this can lead to aileron flutter. My
Sonerai had
balanced ailerons, can someone comment on if the 601XL has balanced
ailerons and if not, could this result in wing flutter?
Roger
-------------------------------------------------------------------------
-----
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of Jeff
Sent: Sunday, November 23, 2008 11:13 AM
To: zenith-list@matronics.com
Subject: Zenith-List: Spreading fear about the XL
Friends, neighbors, and fellow Zenith Enthusiasts,
I have received multiple off-list communications about the
unexplained XL crashes. We now have folks not part of the Zenith
community spreading "information" about the accidents. As I reported on
this list then, a group of LSA competitors advanced negative information
about the XL in person at the September 2007 Zenith Gathering in
Winchester, Virginia. For my part, I have not heard anything conclusive
from the entities looking at the design, including the Zenith Builder's
Analysis Group, Zenith, the NTSB, and European Governments, with two
exceptions. One is the cable tension advisory and the other is the
European action. Neither tells us what is happening unless you believe
that insufficient cable tension is the proper explanation. Others have
failed to find any design problem despite an extensive review. ZAC
conducted a second static load test with acceptable results. But the
impact of all the discussion is becoming clear. In the Second November
Issue, 2008 of Trade-A-Plane, there are three kits for sale and a
completed aircraft. See page 87. Some advertisements have appeared on
this list. Locally, some builders are making the decision to stop work
on their projects. While all losses of human life are mourned without
reservation, especially losses that need not occur, I believe that we
all seek a rational explanation for these events if one exists, not
speculation about what the facts we know might mean.
So let me call on ZAC, the NTSB, the ZBAG, and all other
investigators with the standing to make valid conclusions, to report
whatever they have found or not found at this time in order to limit the
fear of the 601 XL that is currently spreading through the community.
They must speak up now before more damage based on fear is done to our
community.
Please correct me if anyone with standing has provided a
full explanation of the events that are causing these concerns about the
XL.
Jeff Davidson
http://www.matronics.com/contribution< pre>
-------------------------------------------------------------------------
-----
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| Subject: | Re: One more in the air |
Great news, Andy! It is good to see another flying 601XL.
As to your stab adjustment. ZAC says that 3mm ~ 1 degree and they told me not
to adjust it more than 1 degree at a time. I set my forward mount down the 3mm
and did not see as much improvement as I would have liked. I wish I would have
at least doubled it and may still do that in the future. I have heard others
talk about moving the leading edge down 1/2". The choice is your's, but these
are just a few data points to consider.
Good luck,
--------
David Gallagher
601 XL/Jabiru 3300
First flight 7/24/08
Phase I flight test complete 10/16/08
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=216057#216057
Message 15
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| Subject: | Re: Spreading fear about the XL |
Just another comment. Sorry Jay, I truly mean no offense. It is not our
guess or an A/Ps opinion that balancing control surfaces reduces the
possibility of flutter. It's a proven condition of aerodynamics. If not,
I'm sure NOBODY would put lead weights in their ailerons' leading edges.
While I build I also own and fly a Cessna 150 with weight balanced
ailerons. It's cruise speed is just a bit more than some older designs
at about 105mph without balance weights but the VNE is 160mph. This is a
Much larger ratio than the 601 and I don't think it would meet the
certification requirements at that speed without balanced surfaces(the
elevator is balanced as well and also the rudder).
Dirk
----- Original Message -----
From: jaybannist@cs.com
To: zenith-list@matronics.com
Sent: Monday, November 24, 2008 7:43 AM
Subject: Re: Zenith-List: Spreading fear about the XL
Roger,
Not to be argumentative, but I am 74 years old and I practiced
architecture for more than 45 years. So I know a LOT about building
design. That does not qualify me to judge the functional or structural
integrity of another architect's design without knowing the details of
the criteria, the specific goals for the design, and the logic of the
design solution. I have plenty of prejudices when it comes to the
practice of architecture; but I recognize them a such and refrain from
publicly condemning others who do not share my philosophy.
Stating that "ANY unbalanced aileron, regardless of make and model,
would be more likely to flutter and that balancing them could reduce or
even avoid the possibility of flutter" is a prejudiced statement and it
is simply not true. Flutter potential of any control surface is
determined by the totality of the design: size, shape, weight, weight
distribution, pivot location, control system, design speed and so forth
and so on. If the designer makes the right choices (which might
compromise other parts of the design) he can provide a control surface
that will not flutter, period. However, many examples prove that most
designers are not willing to compromise other parts of the airframe to
provide a flutter-free control surface. The fallback is to provide
a20design work-around in the form of balance weights or aerodynamic
balancing surfaces. That is not to criticize the use of balancing. It
is simply a matter of choice. Chris Heintz chose to provide control
surfaces that do not need balancing when operated within the stated
operating limits. If you exceed those limits, you are on your own and
in dangerous territory - "outside the envelope". That is true of any
aircraft and it is where failures occur, including control surface
flutter, wing failure and who knows what.
I'll say it again: If you don't trust the designer, don't fly the
airplanes he has designed. And don't try to "tweek" his design when you
don't know why and how it was designed the way it is.
'Nuff said - Jay in Dallas
Do not archive
-----Original Message-----
From: Roger & Lina Hill <hills@sunflower.com>
To: zenith-list@matronics.com
Sent: Mon, 24 Nov 2008 8:11 am
Subject: RE: Zenith-List: Spreading fear about the XL
Jay;
To be more exact, I believe his point was that ANY unbalanced aileron,
regardless of make and model, would be more likely to flutter and that
balancing them could reduce or even avoid the possibility of flutter.
As for not designing the 601, I don=99t think it is necessary to
design something in order to understand it. My A&P is about 70 years
old, his dad was an A&P as well, so I think he could know through a
combination of training and experience. He is also a homebuilder and so
was his father, who unfortunately died when his homebuilt wing failed in
flight a few years ago.
Roger
-------------------------------------------------------------------------
-----
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of
jaybannist@cs.com
Sent: Monday, November 24, 2008 7:11 AM
To: zenith-list@matronics.com
Subject: Re: Zenith-List: Spreading fear about the XL
Roger.
Your A&P did not design the 601HDS. How could he possibly know t hat
"this could lead to aileron flutter"? Chris Heintz designed the CH200,
CH601, CH601HD, CH601HDS, CH601XL, CH701, CH801 and CH750, all without
aileron balance. The rudder and elevators are not balanced either.
Control surface flutter is a MAJOR concern of all aircraft designers. If
he thought his control surface designs could lead to flutter, don't you
think he would have included some sort of balance?
Exactly how many of these designs (PROPERLY constructed, flown and
maintained) has experienced VERIFIED aileron flutter?
If you don't trust Chris Heintz, stay away from Chris Heinz designed
airplanes. Otherwise, COOL IT!
Jay in Dallas
Do not archive
-----Original Message-----
From: Roger & Lina Hill <hills@sunflower.com>
To: zenith-list@matronics.com
Sent: Sun, 23 Nov 2008 8:50 pm
Subject: RE: Zenith-List: Spreading fear about the XL
Howdy all;
My A&P was looking over my 601HDS and commented that the ailerons were
not counterbalanced. He said this can lead to aileron flutter. My
Sonerai had
balanced ailerons, can someone comment on if the 601XL has balanced
ailerons and if not, could this result in wing flutter?
Roger
&n bsp;
-------------------------------------------------------------------------
-----
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of Jeff
Sent: Sunday, November 23, 2008 11:13 AM
To: zenith-list@matronics.com
Subject: Zenith-List: Spreading fear about the XL
Friends, neighbors, and fellow Zenith Enthusiasts,
I have received multiple off-list communications about the
unexplained XL crashes. We now have folks not part of the Zenith
community spreading "information" about the accidents. As I reported on
this list then, a group of LSA competitors advanced negative information
about the XL in person at the September 2007 Zenith Gathering in
Winchester, Virginia. For my part, I have not heard anything conclusive
from the entities looking at the design, including the Zenith Builder's
Analysis Group, Zenith, the NTSB, and European Governments, with two
exceptions. One is the cable tension advisory and the other is the
European action. Neither tells us what is happening unless you believe
that insufficient cable tension is the proper explanation. Others have
failed to find any design problem despite an extensive review. ZAC
conducted a second static load test with acceptable results. But the
impact of all the discussion is becoming clear. In the Second November
Issue, 2008 of Trade-A-Plane, there are three kits20for sale and a
completed aircraft. See page 87. Some advertisements have appeared on
this list. Locally, some builders are making the decision to stop work
on their projects. While all losses of human life are mourned without
reservation, especially losses that need not occur, I believe that we
all seek a rational explanation for these events if one exists, not
speculation about what the facts we know might mean.
So let me call on ZAC, the NTSB, the ZBAG, and all other
investigators with the standing to make valid conclusions, to report
whatever they have found or not found at this time in order to limit the
fear of the 601 XL that is currently spreading through the community.
They must speak up now before more damage based on fear is done to our
community.
Please correct me if anyone with standing has provided a
full20explanation of the events that are causing these concerns about
the XL.
Jeff Davidson
http://www.matronics.com/contribution< pre>
-------------------------------------------------------------------------
-----
size=2 width="100%" align=center>
Email message sent from CompuServe - visit us today at
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enith-Listhttp://forums.matronics.com
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=================
ution">http://www.matronics.com/contribution
or?Zenith-List">http://www.matronics.com/Navigator?Zenith-List
ilable via the Web Forums!
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| Subject: | Re: One more in the air |
Andy, congratulations.
As to ZAC says that 3mm ~ 1 degree and they told me not to adjust it more than
1 degree at a time correct me if I am wrong but 3mm is NOT approximately 1 degree.
6-T-1 02/05
I leveled my aircraft, place a digital level on a bracket mounted to the (0,0)
line show in 6T1-1 and pitched it 2 degrees.
So too, one has to keep in mind whether we are talking LEADING edge or forward
mount: "I set my forward mount down the 3mm ... others talk about moving the
leading edge down 1/2"."
A 3 mm lowering of the leading edge is a POINT 399 degree change in decalage.
A 3 mm lowering of the forward mount is a POINT 537 degree change in decalage.
A inch (12.7mm) lowering of the leading edge is a 1.69 degree change in decalage.
A inch lowering of the forward mount is a 2.27 degree change in decalage.
A 15 mm lowering of the leading edge is a 2 degree change in decalage.
A 11.2 mm lowering of the forward mount is a 2 degree change in decalage.
give or take...
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=216075#216075
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| Subject: | Re: Spreading fear about the XL |
In this latest discussion, we're all operating on the speculation that the cause
of the handful of wing fold accidents in the 601 have their initial cause in
aileron flutter (a believable hypothesis, given the current lack of any other
concrete data). Flutter at high speeds can destroy an airframe structure in seconds,
and it's pretty easy to imagine a fluttering aileron might overstress
the rear spar/fuselage attach point to failure, allowing the wing to twist until
the lower main spar attachment surrenders, and the wind folds up and over.
Not a pretty scenario.
Some have suggested that balancing the ailerons is the cure. And I remember a recent
YouTube video showing exactly this modification to some Brazilian 601 airframes,
which also sported some other significant modifications. Push pull tubes
would also firm up the play in the aileron control system. That's the beauty
of an experimental aircraft. As the manufacturer of record, we can do these
things legally. But legal isn't always safe, and any departures from what the
kit manufacturer has designed should be done with extreme care and be thoroughly
tested. To Zenith's credit, they've been very approachable when submitting
concepts for improvements or changes.
But the fact remains that the flight control surfaces are not going to flutter
if the cable tensions are anywhere near proper specification. We can add weight
and complexity as added insurance (and to make ourselves feel better), but I
think it's good idea every now and then to take a deep breath and consider how
we fly the airplane as well.
Unless we need to stress the airframe for aerobatics, or are given to rapid control
inputs, or plan on significantly higher cruise airspeeds beyond what the
airframe was designed for, I think we can have some level of confidence in the
design as it is when flown and maintained as specified by Zenith. Sure, I'd
like to hear more from Zenith about what's been found in their collaboration with
the NTSB so far, but I also understand the restrictions in divulging information
prematurely that they must adhere to.
Overall, I think these kinds of discussion are generally positive, as long as we
don't succumb to wild speculation and give in to the temptation to "fix" something
that may not even be a factor. Like everyone else, I look forward to the
day when we can positively identify the smoking gun (if there even is one).
-----Original Message-----
>From: Dirk Zahtilla <ideaz1@sbcglobal.net>
>Sent: Nov 24, 2008 8:14 AM
>To: zenith-list@matronics.com
>Subject: Re: Zenith-List: Spreading fear about the XL
>
>Just another comment. Sorry Jay, I truly mean no offense. It is not our guess
or an A/Ps opinion that balancing control surfaces reduces the possibility of
flutter. It's a proven condition of aerodynamics. If not, I'm sure NOBODY would
put lead weights in their ailerons' leading edges. While I build I also own
and fly a Cessna 150 with weight balanced ailerons. It's cruise speed is just
a bit more than some older designs at about 105mph without balance weights but
the VNE is 160mph. This is a Much larger ratio than the 601 and I don't think
it would meet the certification requirements at that speed without balanced surfaces(the
elevator is balanced as well and also the rudder).
>Dirk
>
> ----- Original Message -----
> From: jaybannist@cs.com
> To: zenith-list@matronics.com
> Sent: Monday, November 24, 2008 7:43 AM
> Subject: Re: Zenith-List: Spreading fear about the XL
>
>
> Roger,
>
> Not to be argumentative, but I am 74 years old and I practiced architecture
for more than 45 years. So I know a LOT about building design. That does not
qualify me to judge the functional or structural integrity of another architect's
design without knowing the details of the criteria, the specific goals for
the design, and the logic of the design solution. I have plenty of prejudices
when it comes to the practice of architecture; but I recognize them a such
and refrain from publicly condemning others who do not share my philosophy.
>
> Stating that "ANY unbalanced aileron, regardless of make and model, would be
more likely to flutter and that balancing them could reduce or even avoid the
possibility of flutter" is a prejudiced statement and it is simply not true.
Flutter potential of any control surface is determined by the totality of the
design: size, shape, weight, weight distribution, pivot location, control system,
design speed and so forth and so on. If the designer makes the right choices
(which might compromise other parts of the design) he can provide a control
surface that will not flutter, period. However, many examples prove that
most designers are not willing to compromise other parts of the airframe to provide
a flutter-free control surface. The fallback is to provide a20design work-around
in the form of balance weights or aerodynamic balancing surfaces. That
is not to criticize the use of balancing. It is simply a matter of choice.
Chris Heintz chose to provide control surfaces that do not need balancing when
operated within the stated operating limits. If you exceed those limits, you
are on your own and in dangerous territory - "outside the envelope". That is
true of any aircraft and it is where failures occur, including control surface
flutter, wing failure and who knows what.
>
> I'll say it again: If you don't trust the designer, don't fly the airplanes
he has designed. And don't try to "tweek" his design when you don't know why
and how it was designed the way it is.
>
> 'Nuff said - Jay in Dallas
> Do not archive
>
>
> -----Original Message-----
> From: Roger & Lina Hill <hills@sunflower.com>
> To: zenith-list@matronics.com
> Sent: Mon, 24 Nov 2008 8:11 am
> Subject: RE: Zenith-List: Spreading fear about the XL
>
>
> Jay;
>
> To be more exact, I believe his point was that ANY unbalanced aileron, regardless
of make and model, would be more likely to flutter and that balancing them
could reduce or even avoid the possibility of flutter. As for not designing
the 601, I dont think it is necessary to design something in order to understand
it. My A&P is about 70 years old, his dad was an A&P as well, so I think
he could know through a combination of training and experience. He is also a
homebuilder and so was his father, who unfortunately died when his homebuilt
wing failed in flight a few years ago.
>
> Roger
>
>
>------------------------------------------------------------------------------
>
> From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matronics.com] On Behalf Of jaybannist@cs.com
> Sent: Monday, November 24, 2008 7:11 AM
> To: zenith-list@matronics.com
> Subject: Re: Zenith-List: Spreading fear about the XL
>
> Roger.
>
> Your A&P did not design the 601HDS. How could he possibly know t hat "this
could lead to aileron flutter"? Chris Heintz designed the CH200, CH601, CH601HD,
CH601HDS, CH601XL, CH701, CH801 and CH750, all without aileron balance. The
rudder and elevators are not balanced either. Control surface flutter is a MAJOR
concern of all aircraft designers. If he thought his control surface designs
could lead to flutter, don't you think he would have included some sort of
balance?
>
> Exactly how many of these designs (PROPERLY constructed, flown and maintained)
has experienced VERIFIED aileron flutter?
>
> If you don't trust Chris Heintz, stay away from Chris Heinz designed airplanes.
Otherwise, COOL IT!
>
> Jay in Dallas
> Do not archive
>
>
> -----Original Message-----
> From: Roger & Lina Hill <hills@sunflower.com>
> To: zenith-list@matronics.com
> Sent: Sun, 23 Nov 2008 8:50 pm
> Subject: RE: Zenith-List: Spreading fear about the XL
> Howdy all;
>
> My A&P was looking over my 601HDS and commented that the ailerons were not counterbalanced.
He said this can lead to aileron flutter. My Sonerai had
> balanced ailerons, can someone comment on if the 601XL has balanced ailerons
and if not, could this result in wing flutter?
>
> Roger
>
> &n bsp;
>
>
>------------------------------------------------------------------------------
>
> From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matronics.com] On Behalf Of Jeff
> Sent: Sunday, November 23, 2008 11:13 AM
> To: zenith-list@matronics.com
> Subject: Zenith-List: Spreading fear about the XL
>
> Friends, neighbors, and fellow Zenith Enthusiasts,
>
> I have received multiple off-list communications about the unexplained
XL crashes. We now have folks not part of the Zenith community spreading
"information" about the accidents. As I reported on this list then, a group
of LSA competitors advanced negative information about the XL in person at the
September 2007 Zenith Gathering in Winchester, Virginia. For my part, I have
not heard anything conclusive from the entities looking at the design, including
the Zenith Builder's Analysis Group, Zenith, the NTSB, and European Governments,
with two exceptions. One is the cable tension advisory and the other
is the European action. Neither tells us what is happening unless you believe
that insufficient cable tension is the proper explanation. Others have failed
to find any design problem despite an extensive review. ZAC conducted a second
static load test with acceptable results. But the impact of all the discussion
is becoming clear. In the Second November Issue, 2008 of Trade-A-Plane,
there are three kits20for sale and a completed aircraft. See page 87. Some
advertisements have appeared on this list. Locally, some builders are making
the decision to stop work on their projects. While all losses of human life
are mourned without reservation, especially losses that need not occur, I believe
that we all seek a rational explanation for these events if one exists, not
speculation about what the facts we know might mean.
>
> So let me call on ZAC, the NTSB, the ZBAG, and all other investigators
with the standing to make valid conclusions, to report whatever they have
found or not found at this time in order to limit the fear of the 601 XL that
is currently spreading through the community. They must speak up now before
more damage based on fear is done to our community.
>
> Please correct me if anyone with standing has provided a full20explanation
of the events that are causing these concerns about the XL.
>
> Jeff Davidson
>
>
>
> http://www.matronics.com/contribution< pre>
>
>------------------------------------------------------------------------------
> size=2 width="100%" align=center>
> Email message sent from CompuServe - visit us today at http://www.cs.com
> http://www.matronics.com/contributionhttp://www.matronics.com/Navigator?Zenith-Listhttp://forums.matronics.com
>
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>ution">http://www.matronics.com/contribution
>or?Zenith-List">http://www.matronics.com/Navigator?Zenith-List
>ilable via the Web Forums!
>p://forums.matronics.com
>
>------------------------------------------------------------------------------
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>
>
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| Subject: | Re: Spreading fear about the XL |
Jay, what you say makes good sense. Course, I may be the only XL builder and
flyer that has had aileron flutter and got out of it without the wings comi
ng off. It's like having a rev'ed up chain saw drop in your lap while flying
. Something I don't ever want to have again. I really like my XL, it does wh
at I want and has from when I bought the kit and built it. Still, I also saw
the Challenger blow up so my faith that a designer, any designer, or team o
f experts could miss something is not absolute. I'm going to modify my XL ov
er the holidays by removing the cables and installing push/pull rods similar
to the ones I built for my=C2-RV-8a.=C2-I hope that reduces the potenti
al for flutter. At least it will increase my piece of mind. Never the less,
I will continue flying my XL, not in some blind faith that CH designed a per
fect plane, but that I built and maintain a safe plane.=C2-Trust is foolis
h if blind. Best regards, Bill of Georgia=C2-
-----Original Message-----
From: jaybannist@cs.com
Sent: Mon, 24 Nov 2008 10:43 am
Subject: Re: Zenith-List: Spreading fear about the XL
Roger,
Not to be argumentative, but I am 74 years old and I practiced architecture
for more than 45 years. So I know a LOT about building design.=C2- That do
es not qualify me to judge the functional or structural integrity of another
architect's design without knowing the details of the criteria,=C2- the s
pecific goals for the design, and the logic of the design solut
ion.=C2- I have plenty of prejudices when it comes to the practice of arch
itecture; but I recognize them a such and refrain from publicly condemning o
thers who do not share my philosophy. =C2-
Stating that "ANY unbalanced aileron, regardless of make and model, =C2-wo
uld be more likely to flutter and that balancing them could reduce or even a
void =C2-the possibility of flutter" is a prejudiced statement and it is s
imply not true.=C2- Flutter potential of any control surface is determined
by the totality of the design: size, shape, weight, weight distribution, pi
vot location, control system, design speed and so forth and so on.=C2- If
the designer makes the right choices (which might compromise other parts of
the design) he can provide a control surface that will not flutter, period.
However, many examples prove that most designers are not willing to compromi
se other parts of the airframe to provide a flutter-free control surface.
=C2- The fallback is to provide a20design work-around in the form of balan
ce weights or aerodynamic balancing surfaces. That is not to criticize the u
se of balancing.=C2- It is simply a matter of choice. Chris Heintz chose t
o provide control surfaces that do not need balancing when operated within t
he stated operating limits.=C2- If you exceed those limits, you are on you
r own and in dangerous territory - "outside the envelope".=C2- That is tru
e of any aircraft and it is where failures occur, including control surface
flutter, wing failure and who knows what.=C2-
I'll say
it again:=C2- If you don't trust the designer, don't fly the airplanes he
has designed.=C2- And don't try to "tweek" his design when you don't know
why and how it was designed the way it is.
'Nuff said - Jay in Dallas
Do not archive
-----Original Message-----
From: Roger & Lina Hill <hills@sunflower.com>
Sent: Mon, 24 Nov 2008 8:11 am
Subject: RE: Zenith-List: Spreading fear about the XL
=C2-
Jay;
=C2-
To be more exact, I believe his point was that ANY unbalanced aileron, regar
dless of make and model, =C2-would be more likely to flutter and that bala
ncing them could reduce or even avoid =C2-the possibility of flutter.=C2
- As for not designing the 601, I don=99t think it is necessary to d
esign something in order to understand it. My A&P is about 70 years old, his
dad was an A&P as well, so I think he could know through a combination of t
raining and experience. He is also a homebuilder and so was his father, who
unfortunately died when his homebuilt wing failed in flight a few years ago.
=C2-
Roger
=C2-
=C2-
=C2-
From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-serve
r@matronics.com] On Behalf Of jaybannist@cs.com
Sent: Monday, November 24, 2008 7:11 AM
Subject: Re: Zenith-List: Spreading fear about the XL
=C2-
Roger.=C2-
Your A&P did not design the 601HDS.=C2- How could he possibly know t hat "
this could lead to aileron
flutter"?=C2- Chris Heintz designed the CH200, CH601, CH601HD, CH601HDS,
CH601XL, CH701, CH801 and CH750, all without aileron balance. The rudder and
elevators are not balanced either. Control surface flutter is a MAJOR conce
rn of all aircraft designers. If he thought his control surface designs coul
d lead to flutter, don't you think he would have included some sort of balan
ce?
Exactly how many of these designs (PROPERLY constructed, flown and maintaine
d) has experienced VERIFIED aileron flutter?
If you don't trust Chris Heintz, stay away from Chris Heinz designed airplan
es. Otherwise, COOL IT!
Jay in Dallas
Do not archive
=C2-
=C2-
-----Original Message-----
From: Roger & Lina Hill <hills@sunflower.com>
Sent: Sun, 23 Nov 2008 8:50 pm
Subject: RE: Zenith-List: Spreading fear about the XL
Howdy all;
=C2-
My A&P was looking over my 601HDS and commented that the ailerons were not c
ounterbalanced.=C2- He said this can lead to aileron flutter.=C2- My Son
erai had
balanced ailerons, can someone comment on if the 601XL has balanced ailerons
and if not, could this result in wing flutter?
=C2-
Roger
=C2-
&n bsp;
=C2-
From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-serve
r@matronics.com] On Behalf Of Jeff
Sent: Sunday, November 23, 2008 11:13 AM
Subject: Zenith-List: Spreading fear about the XL
=C2-
Friends, neighbors, and fellow Zenith Enthusiasts,=0
A
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2- I have re
ceived multiple off-list communications about the unexplained XL crashes.
=C2- We now have folks not part of the Zenith community spreading "informa
tion" about the accidents.=C2- As I reported on this list then, a group of
LSA competitors advanced negative information about the XL in person at the
September 2007 Zenith Gathering in Winchester, Virginia.=C2- For my part,
I have not heard anything conclusive from the entities looking at the desig
n, including the Zenith Builder's Analysis Group, Zenith, the NTSB, and Euro
pean Governments, with two exceptions.=C2- One is the cable tension adviso
ry and the other is the European action.=C2- Neither tells us what is happ
ening unless you believe that insufficient cable tension is the proper expla
nation.=C2- Others have failed to find any design problem despite an exten
sive review.=C2- ZAC conducted a second static load test with acceptable r
esults.=C2- But the impact of all the discussion is becoming clear.=C2-
In the Second November Issue, 2008 of Trade-A-Plane, there are three kits20f
or sale and a completed aircraft.=C2- See page 87. =C2-Some advertisemen
ts have appeared on this list. =C2-Locally, some builders are making the d
ecision to stop work on their projects.=C2- While all losses of human life
are mourned without reservation, especially losses that need not occur, I b
elieve that we all seek a rational explanation for these events if one exist
s
, not speculation about what the facts we know might mean.=C2-
=C2-
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2- So let me
call on ZAC, the NTSB, the ZBAG, and all other investigators with the stand
ing to make valid conclusions, to report whatever they have found or not fou
nd at this time in order to limit the fear of the 601 XL that is currently s
preading through the community.=C2- They must speak up now before more dam
age based on fear is done to our community.
=C2-
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2- Please co
rrect me if anyone with standing has provided a full20explanation of the eve
nts that are causing these concerns about the XL.
=C2-
Jeff Davidson
=C2-
=C2-
=C2- =C2-=C2-
=C2-
=C2-
http://www.matronics.com/contribution
< pre>
size=2 width="100%" align=center>
Email message sent from CompuServe - visit us today at http://www.cs.com
=C2-
=C2-
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http://www.matronics.com/Navigator?Zenith-List
http://forums.matronics.com
================
================
tion">http://www.matronics.com/contribution
=========
r?Zenith-List">http://www.matronics.com/Navigator?Zenith-List
=========
lable via the Web Forums!
://forums.matronics.com
=========
Email message sent from CompuServe - visit us today at http://www.cs.com
-
-= -- Please Support Your Lists This Month --
-= (And Get Some AWESOME FREE Gifts!)
-
-= November is the Annual List Fund Raiser. Click on
-= the Contribution link below to find out more about
-= this year's Terrific Free Incentive Gifts!
-
-= List Contribution Web Site:
-
-= --> http://www.matronics.com/contribution
-
-= Thank you for your generous support!
-
-= -Matt Dralle, List Admin.
-
-========================
-= - The Zenith-List Email Forum -
-= Use the Matronics List Features Navigator to browse
-= the many List utilities such as List Un/Subscription,
-= Archive Search & Download, 7-Day Browse, Chat, FAQ,
-= Photoshare, and much much more:
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-
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-= Same great content also available via the Web Forums!
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-
-========================
=3D=======================
< pre>
size=2 width="100%" align=center>
Email message sent from CompuServe - visit us today at http://www.cs.com
=C2-
=C2-
http://www.matronics.com/contribution
http://www.matronics.com/Navigator?Zenith-List
http://forums.matronics.com
================
================
tion">http://www.matronics.com/contribution
=========
r?Zenith-List">http://www.matronics.com/Navigator?Zenith-List
=========
lable via the Web Forums!
://forums.matronics.com
=========
Email message sent from CompuServe - visit us today at http://www.cs.com
-
-= -- Please Support Your Lists This Month --
-= (And Get Some AWESOME FREE Gifts!)
-
-= November is the Annual List Fund Raiser. Click on
-= the Contribution link below to find out more about
-= this year's Terrific Free Incentive Gifts!
-
-= List Contribution Web Site:
-
-= --> http://www.matronics.com/contribution
-
-= Thank you for your generous support!
-
-= -Matt Dralle, List Admin.
-
-======================3
D========================
=============
-= - The Zenith-List Email Forum -
-= Use the Matronics List Features Navigator to browse
-= the many List utilities such as List Un/Subscription,
-= Archive Search & Download, 7-Day Browse, Chat, FAQ,
-= Photoshare, and much much more:
-
-= --> http://www.matronics.com/Navigator?Zenith-List
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Message 19
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|
| Subject: | Re: Spreading fear about the XL |
Dirk,
I don't mean to offend either, but since you didn't read and understand what
I wrote, I will not respond.
Jay io Dallas
Do not archive
-----Original Message-----
From: Dirk Zahtilla <ideaz1@sbcglobal.net>
Sent: Mon, 24 Nov 2008 10:14 am
Subject: Re: Zenith-List: Spreading fear about the XL
Just another comment. Sorry Jay, I truly mean no
offense. It is not our guess or an A/Ps opinion that balancing control surfa
ces
reduces the possibility of flutter. It's a proven condition of aerodynamics.
If
not, I'm sure NOBODY would put lead weights in their ailerons' leading edges
.
While I build I also own and fly a Cessna 150 with weight balanced ailerons.
It's cruise speed is just a bit more than some older designs at about
105mph=C2-without balance weights but the VNE is 160mph. This is a Much la
rger
ratio than the 601 and I don't think it would meet the certification
requirements at that speed without balanced surfaces(the elevator is balance
d as
well and also the rudder).
Dirk
=C2-
----- Original Message -----
From:
jaybannist@cs.com
Sent: Monday, November 24, 2008 7:43
AM
Subject: Re: Zenith-List: Spreading fear
about the XL
Roger,
Not
to be argumentative, but I am 74 years old and I practiced architecture fo
r
more than 45 years. So I know a LOT about
building design.=C2- That does not
qualify me to judge the functional or structural integrity of another
architect's design without knowing the details of the criteria,=C2- the
specific goals for the design, and the logic of the design solution.=C2
- I
have plenty of prejudices when it comes to the practice of architecture; b
ut I
recognize them a such and refrain from publicly condemning others who do n
ot
share my philosophy. =C2-
Stating that "ANY unbalanced
aileron, regardless of make and model, =C2-would be more likely to flutt
er
and that balancing them could reduce or even avoid =C2-the possibility o
f
flutter" is a prejudiced statement and it is simply not true.=C2- Flutte
r
potential of any control surface is determined by the totality of the desi
gn:
size, shape, weight, weight distribution, pivot location, control system,
design speed and so forth and so on.=C2- If the designer makes the right
choices (which might compromise other parts of the design) he can provide
a
control surface that will not flutter, period. However, many examples prov
e
that most designers are not willing to compromise other parts of the airfr
ame
to provide a flutter-free control surface.=C2- The fallback is to provid
e
a20design work-around in the form of balance weights or aerodynamic balanc
ing
surfaces. That is not to criticize the use of balancing.=C2- It is simpl
y a
matter of choice. Chris Heintz=2
0chose to provide control surfaces that do not
need balancing when operated within the stated operating limits.=C2- If
you
exceed those limits, you are on your own and in dangerous territory - "out
side
the envelope".=C2- That is true of any aircraft and it is where failures
occur, including control surface flutter, wing failure and who knows
what.=C2-
I'll say it again:=C2- If you don't trust the designer,
don't fly the airplanes he has designed.=C2- And don't try to "tweek" hi
s
design when you don't know why and how it was designed the way it is.
'Nuff said - Jay in Dallas
Do not
archive
-----Original Message-----
From: Roger & Lina Hill
<hills@sunflower.com>
Sent: Mon, 24
Nov 2008 8:11 am
Subject: RE: Zenith-List: Spreading fear about the
XL
=C2-
Jay;
=C2-
To be more exact, I
believe his point was that ANY unbalanced aileron, regardless of make and
model, =C2-would be more likely to flutter and that balancing them could
reduce or even avoid =C2-the possibility of flutter.=C2- As for not
designing the 601, I don=99t think it is necessary to design somethi
ng in order
to understand it. My A&P is about 70 years old, his dad was an A&P as
well, so I think he could know through a combination of training and =0
A experience. He is also a homebuilder and so was his father, who unfortuna
tely
died when his homebuilt wing failed in flight a few years ago.
=C2-
Roger
=C2-
=C2-
=C2-
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com]
On Behalf Of jaybannist@cs.com
Sent: Monday, November 24, 2008 7:11
AM
Subject: Re: Zenith-List: Spreading fear
about the XL
=C2-
Roger.=C2-
Your A&P
did not design the 601HDS.=C2- How could he possibly know t hat "this co
uld
lead to aileron flutter"?=C2- Chris Heintz designed the CH200, CH601,
CH601HD, CH601HDS, CH601XL, CH701, CH801 and CH750, all without aileron
balance. The rudder and elevators are not balanced either. Control surface
flutter is a MAJOR concern of all aircraft designers. If he thought his
control surface designs could lead to flutter, don't you think he would ha
ve
included some sort of balance?
Exactly how many of these designs
(PROPERLY constructed, flown and maintained) has experienced VERIFIED aile
ron
flutter?
If you don't trust Chris Heintz, stay away from Chris Heinz
designed airplanes. Otherwise, COOL IT!
Jay in Dallas
Do not
archive
=C2-
=C2-
-----Original Message-----
From: Roger
& Lina Hill <hills@sunflower.com
>
Sent:
Sun, 23 Nov 2008 8:50 pm
Subject: RE: Zenith-List: Spreading fear about the
XL
Howdy
all;
=C2-
My A&P was
looking over my 601HDS and commented that the ailerons were not
counterbalanced.=C2- He said this can lead to aileron flutter.=C2- My
Sonerai had
balanced ailerons,
can someone comment on if the 601XL has balanced ailerons and if not, coul
d
this result in wing flutter?
=C2-
Roger
=C2-
&n
bsp;
=C2-
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com]
On Behalf Of Jeff
Sent: Sunday, November 23, 2008 11:13
AM
Subject: Zenith-List: Spreading fear
about the XL
=C2-
Friends, neighbors, and fellow
Zenith Enthusiasts,
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-
I have received multiple off-list communications about the unexplained XL
crashes.=C2- We now have folks not part of the Zenith community spreadin
g
"information" about the accidents.=C2- As I reported on this list then,
a
group of LSA competitors=2
0advanced negative information about the XL in person
at the September 2007 Zenith Gathering in Winchester, Virginia.=C2- For
my
part, I have not heard anything conclusive from the entities looking at th
e
design, including the Zenith Builder's Analysis Group, Zenith, the NTSB, a
nd
European Governments, with two exceptions.=C2- One is the cable tension
advisory and the other is the European action.=C2- Neither tells us what
is
happening unless you believe that insufficient cable tension is the proper
explanation.=C2- Others have failed to find any design problem despite a
n
extensive review.=C2- ZAC conducted a second static load test with
acceptable results.=C2- But the impact of all the discussion is becoming
clear.=C2- In the Second November Issue, 2008 of Trade-A-Plane, there ar
e
three kits20for sale and a completed aircraft.=C2- See page 87. =C2-So
me
advertisements have appeared on this list. =C2-Locally, some builders ar
e
making the decision to stop work on their projects.=C2- While all losses
of
human life are mourned without reservation, especially losses that need no
t
occur, I believe that we all seek a rational explanation for these events
if
one exists, not speculation about what the facts we know might mean.=C2
-
=C2-
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-
So let me call on ZAC, the NTSB, the ZBAG, and all other investigators wit
h
the standing to make valid conclusions, to report whatever they have found
or
not found at this time in order to limit the fear of the 601 XL that is
currently spreading through the community.=C2- They must speak up now be
fore
more damage based on fear is done to our community.
=C2-
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-
Please correct me if anyone with standing has provided a full20explanation
of
the events that are causing these concerns about the
XL.
=C2-
Jeff
Davidson
=C2-
=C2-
=C2-
=C2-=C2-
=C2-
=C2-
http://www.matronics.com/contribution
<
pre>
size=2 width="100%" align=center>
Email message sent from CompuServe -
visit us today at http://www.cs.com
=C2-
=C2-
http://www.matronics.com/contribution
http://www.matronics.com/Navigator?Zenith-List
http://forums.matronics.com
=================
=================
ution">http://www.matronics.com/contribution
or?Zenith-List">http://www.matronics.com/Navigator?Zenith-List
ilable via the Web Forums!
p://forums.matronics.com
Email message sent from Co
mpuServe - visit us today at http://www.cs.com
href="http://www.matronics.com/contribution">http://www.matronics.com/chre
f="http://www.matronics.com/Navigator?Zenith-List">http://www.matronhref
="http://forums.matronics.com">http://forums.matronics.com
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=======
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Message 20
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| Subject: | Chat Room Reminder |
Please join us for our Monday evening chat room starting around 8:00 PM
Eastern Time.
<blocked::blocked::blocked::blocked::blocked::blocked::http://www.mykitairpl
ane.com/chat/> http://www.mykitairplane.com/chat/
George
Do Not Archive
Message 21
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| Subject: | Re: Spreading fear about the XL |
Bill, you had flutter. I assume after the incident the control cables
were checked on your aircraft? If so, what did you find ????
In your specific case, were the cables tensioned as per plans at 30 + -
pounds ??
SW
----- Original Message -----
From: japhillipsga@aol.com
To: zenith-list@matronics.com
Sent: Monday, November 24, 2008 11:05 AM
Subject: Re: Zenith-List: Spreading fear about the XL
Jay, what you say makes good sense. Course, I may be the only XL
builder and flyer that has had aileron flutter and got out of it without
the wings coming off. It's like having a rev'ed up chain saw drop in
your lap while flying. Something I don't ever want to have again. I
really like my XL, it does what I want and has from when I bought the
kit and built it. Still, I also saw the Challenger blow up so my faith
that a designer, any designer, or team of experts could miss something
is not absolute. I'm going to modify my XL over the holidays by removing
the cables and installing push/pull rods similar to the ones I built for
my RV-8a. I hope that reduces the potential for flutter. At least it
will increase my piece of mind. Never the less, I will continue flying
my XL, not in some blind faith that CH designed a perfect plane, but
that I built and maintain a safe plane. Trust is foolish if blind. Best
regards, Bill of Georgia
-----Original Message-----
From: jaybannist@cs.com
To: zenith-list@matronics.com
Sent: Mon, 24 Nov 2008 10:43 am
Subject: Re: Zenith-List: Spreading fear about the XL
Roger,
Not to be argumentative, but I am 74 years old and I practiced
architecture for more than 45 years. So I know a LOT about building
design. That does not qualify me to judge the functional or structural
integrity o f another architect's design without knowing the details of
the criteria, the specific goals for the design, and the logic of the
design solution. I have plenty of prejudices when it comes to the
practice of architecture; but I recognize them a such and refrain from
publicly condemning others who do not share my philosophy.
Stating that "ANY unbalanced aileron, regardless of make and model,
would be more likely to flutter and that balancing them could reduce or
even avoid the possibility of flutter" is a prejudiced statement and it
is simply not true. Flutter potential of any control surface is
determined by the totality of the design: size, shape, weight, weight
distribution, pivot location, control system, design speed and so forth
and so on. If the designer makes the right choices (which might
compromise other parts of the design) he can provide a control surface
that will not flutter, period. However, many examples prove that most
designers are not willing to compromise other parts of the airframe to
provide a flutter-free control surface. The fallback is to provide
a20design work-around in the form of balance weights or aerodynamic
balancing surfaces. That is not to criticize the use of balancing. It
is simply a matter of choice. Chris Heintz chose to provide control
surfaces that do not need balancing when operated within the stated
operating limits. If yo u exceed those limits, you are on your own and
in dangerous territory - "outside the envelope". That is true of any
aircraft and it is where failures occur, including control surface
flutter, wing failure and who knows what.
I'll say it again: If you don't trust the designer, don't fly the
airplanes he has designed. And don't try to "tweek" his design when you
don't know why and how it was designed the way it is.
'Nuff said - Jay in Dallas
Do not archive
-----Original Message-----
From: Roger & Lina Hill <hills@sunflower.com>
To: zenith-list@matronics.com
Sent: Mon, 24 Nov 2008 8:11 am
Subject: RE: Zenith-List: Spreading fear about the XL
Jay;
To be more exact, I believe his point was that ANY unbalanced aileron,
regardless of make and model, would be more likely to flutter and that
balancing them could reduce or even avoid the possibility of flutter.
As for not designing the 601, I don=99t think it is necessary to
design something in order to understand it. My A&P is about 70 years
old, his dad was an A&P as well, so I think he could know through a
combination of training and experience. He is also a homebuilder and so
was his father, who unfortunately died when his homebuilt wing failed in
flight a few years ago.
Roger
-------------------------------------------------------------------------
-----
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of
jaybannist@cs.com
Sent: Monday, November 24, 2008 7:11 AM
To: zenith-list@matronics.com
Subject: Re: Zenith-List: Spreading fear about the XL
Roger.
Your A&P did not design the 601HDS. How could he possibly know t hat
"this could lead to aileron flutter"? Chris Heintz designed the CH200,
CH601, CH601HD, CH601HDS, CH601XL, CH701, CH801 and CH750, all without
aileron balance. The rudder and elevators are not balanced either.
Control surface flutter is a MAJOR concern of all aircraft designers. If
he thought his control surface designs could lead to flutter, don't you
think he would have included some sort of balance?
Exactly how many of these designs (PROPERLY constructed, flown and
maintained) has experienced VERIFIED aileron flutter?
If you don't trust Chris Heintz, stay away from Chris Heinz designed
airplanes. Otherwise, COOL IT!
Jay in Dallas
Do not archive
-----Original Message-----
From: Roger & Lina Hill <hills@sunflower.com>
To: zenith-list@matronics.com
Sent: Sun, 23 Nov 2008 8:50 pm
Subject: RE: Zenith-List: Spreading fear about the XL
Howdy all;
My A&P was looking over my 601HDS and commented that the ailerons were
not counterbalanced. He said this can lead to aileron flutter. My
Sonerai had
balanced ailerons, can someone comment on if the 601XL has balanced
ailerons and if not, could this result in wing flutter?
Roger
&n bsp;
-------------------------------------------------------------------------
-----
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of Jeff
Sent: Sunday, November 23, 2008 11:13 AM
To: zenith-list@matronics.com
Subject: Zenith-List: Spreading fear about the XL
Friends, neighbors, and fellow Zenith Enthusiasts,
I have received multiple off-list communications about the
unexplained XL crashes. We now have folks not part of the Zenith
community spreading "information" about the accidents. As I reported on
this list then, a group of LSA competitors advanced negative information
about the XL in person at the September 2007 Zenith Gathering in
Winchester, Virginia. For my part, I have not heard anything conclusive
from the entities looking at the design, including the Zenith Builder's
Analysis Group, Zenith, the NTSB, and European Governments, with two
exceptions. One is the cable tension advisory and the other is the
European action. Neither tells us what is happening unless you believe
that insufficient cable tension is the proper explanation. Others have
failed to find any design problem despite an extensive review. ZAC
conducted a second static load test with acceptable results. But the
impact of all the discussion is becoming clear. In the Second November
Issue, 2008 of Trade-A-Plane, there are thre e kits20for sale and a
completed aircraft. See page 87. Some advertisements have appeared on
this list. Locally, some builders are making the decision to stop work
on their projects. While all losses of human life are mourned without
reservation, especially losses that need not occur, I believe that we
all seek a rational explanation for these events if one exists, not
speculation about what the facts we know might mean.
So let me call on ZAC, the NTSB, the ZBAG, and all other
investigators with the standing to make valid conclusions, to report
whatever they have found or not found at this time in order to limit the
fear of the 601 XL that is currently spreading through the community.
They must speak up now before more damage based on fear is done to our
community.
Please correct me if anyone with standing has provided a
full20explanation of the events that ar e causing these concerns about
the XL.
Jeff Davidson
http://www.matronics.com/contribution< pre>
-------------------------------------------------------------------------
-----
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http://www.matronics.com/contributionhttp://www.matronics.com/Navigator?Z
enith-List
http://forums.matronics.com
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ution">http://www.matronics.com/contribution
or?Zenith-List">http://www.matronics.com/Navigator?Zenith-List
ilable via the Web Forums!
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Message 22
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| Subject: | Re: Spreading fear about the XL |
Dirk,
pull up the archives, i brought up the issue of VNE and Max manauvering speeds
over one year ago, but the back room engineers ignored it.
Fly it and follow the specs. My guess is the guys flying and that augered in ignored
the flight envelope of the aircraft. BUILD IT TO PLANS AND FLY IT TO SPECS.
Time to move on folks,
Juan
-----Original Message-----
>From: Dirk Zahtilla <ideaz1@sbcglobal.net>
>Sent: Nov 24, 2008 10:56 AM
>To: zenith-list@matronics.com
>Subject: Re: Zenith-List: Spreading fear about the XL
>
>You forgot the 640 which also has unbalanced ailerons HOWEVER... it has push-pull
tubes instead of cables and boxed wing spars (more related to the load carying
capacity).The margin between cruise and VNE is much closer than the XL design.
Maybe we need to look at this!? As I look at the designs, they become capable
of increasingly high cruise speeds and with builders putting more h.p. in
it becomes very easy to reach VNE very quickly by entering even a very shallow
dive. (also the rudder on the 6,7,&8 series ARE balanced, note the portion
of the rudder ahead of the hinge points...this is aerodynamic balance as opposed
to weight balance).
>
>I think that what we are seeing is two groups of builders here: one group who
builds and fly's well within the specs of the design, and one group that wants
to achieve everything to the edge of the envelope and perhaps a bit beyond. One
group is made of builder/flyers, and one group is made of experimenter builders/test
pilots. This latter group will always push aircraft design firms to
re-examine their designs and hopefully this will benefit the first group who will
end up flying increasingly safe and more capable aircraft.
>
>I'm sure that no-one on this list means to offend the builder/flyer group, I know
I don't. We are just part of the group that reaches out to extend our potential.
>
>I am building a 601XL (which I may re-designate as 601XLA(airobat)orM(modified)
just to make it clear that it is not totally to plans) As I have said before
I will use push-pull tubes for the ailerons and elevator and balance both as
well. The ailerons will move the hingepoint rearward and the elevator will use
weights in the tips which will be attached to the elevator instead of the horizontal
stab. I will also use a boxed spar in the wing that meets at the center
instead of bolting on at the outer part of the fuselage.
>
>Dirk Z
> ----- Original Message -----
> From: jaybannist@cs.com
> To: zenith-list@matronics.com
> Sent: Monday, November 24, 2008 5:11 AM
> Subject: Re: Zenith-List: Spreading fear about the XL
>
>
> Roger.
>
> Your A&P did not design the 601HDS. How could he possibly know that "this could
lead to aileron flutter"? Chris Heintz designed the CH200, CH601, CH601HD,
CH601HDS, CH601XL, CH701, CH801 and CH750, all without aileron balance. The
rudder and elevators are not balanced either. Control surface flutter is a MAJOR
concern of all aircraft designers. If he thought his control surface designs
could lead to flutter, don't you think he would have included some sort of
balance?
>
> Exactly how many of these designs (PROPERLY constructed, flown and maintained)
has experienced VERIFIED aileron flutter?
>
> If you don't trust Chris Heintz, stay away from Chris Heinz designed airplanes.
Otherwise, COOL IT!
>
> Jay in Dallas
> Do not archive
>
>
> -----Original Message-----
> From: Roger & Lina Hill <hills@sunflower.com>
> To: zenith-list@matronics.com
> Sent: Sun, 23 Nov 2008 8:50 pm
> Subject: RE: Zenith-List: Spreading fear about the XL
>
>
> Howdy all;
>
> My A&P was looking over my 601HDS and commented that the ailerons were not counterbalanced.
He said this can lead to aileron flutter. My Sonerai had
> balanced ailerons, can someone comment on if the 601XL has balanced ailerons
and if not, could this result in wing flutter?
>
> Roger
>
>
>------------------------------------------------------------------------------
>
> From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matronics.com] On Behalf Of Jeff
> Sent: Sunday, November 23, 2008 11:13 AM
> To: zenith-list@matronics.com
> Subject: Zenith-List: Spreading fear about the XL
>
> Friends, neighbors, and fellow Zenith Enthusiasts,
>
> I have received multiple off-list communications about the unexplained
XL crashes. We now have folks not part of the Zenith community spreading
"information" about the accidents. As I reported on this list then, a group
of LSA competitors advanced negative information about the XL in person at the
September 2007 Zenith Gathering in Winchester, Virginia. For my part, I have
not heard anything conclusive from the entities looking at the design, including
the Zenith Builder's Analysis Group, Zenith, the NTSB, and European Governments,
with two exceptions. One is the cable tension advisory and the other
is the European action. Neither tells us what is happening unless you believe
that insufficient cable tension is the proper explanation. Others have failed
to find any design problem despite an extensive review. ZAC conducted a second
static load test with acceptable results. But the impact of all the discussion
is becoming clear. In the Second November Issue, 2008 of Trade-A-Plane,
there are three kits for sale and a completed aircraft. See page 87. Some
advertisements have appeared on this list. Locally, some builders are making
the decision to stop work on their projects. While all losses of human life are
mourned without reservation, especially losses that need not occur, I believe
that we all seek a rational explanation for these events if one exists, not
speculation about what the facts we know might mean.
>
> So let me call on ZAC, the NTSB, the ZBAG, and all other investigators
with the standing to make valid conclusions, to report whatever they have
found or not found at this time in order to limit the fear of the 601 XL that
is currently spreading through the community. They must speak up now before
more damage based on fear is done to our community.
>
> Please correct me if anyone with standing has provided a full explanation
of the events that are causing these concerns about the XL.
>
> Jeff Davidson
>
>
>
> http://www.matronics.com/contribution< pre>
>
>------------------------------------------------------------------------------
> Email message sent from CompuServe - visit us today at http://www.cs.com
>
>
Message 23
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| Subject: | Re: One more in the air |
check the CG first. congrads.
-----Original Message-----
>From: "Dr. Andrew Elliott" <a.s.elliott@cox.net>
>Sent: Nov 24, 2008 10:43 AM
>To: Zenith-List Digest Server <zenith-list@matronics.com>
>Subject: Zenith-List: One more in the air
>
>Gang:
>
>I am happy to report that N601GE, a Zodiac 601XL/TD, powered by a 3100 Corvair,
took to the skies this morning for the first time at KFFZ, Mesa, AZ. 0.7 hours,
no engine problems.
>
>Horizontal stabilizer likely needs some incidence adjustment, as full aft trim
was needed at 100 MIAS and left arm below that. Otherwise no airframe problems.
>
>More to report as flight testing continues...
>
>Andy Elliott, Mesa, AZ
Message 24
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|
| Subject: | Re: Spreading fear about the XL |
Juan
That is all it is, a guess, some of us want to know as much as possible to
avoid mistakes and to build a good solid plane. I think there has been some
good conversation on the subject of properly tensioning control cables to
avoid the "possibility" of flutter. I agree with building it to plans and
flying within the design limitations but coming to the conclusion that all
of them augured because of exceeding VNE and maneuvering speeds is a little
over the top. From Bill's account, he experienced flutter, and he wasn't
busting any design limits and later found his cables were not tensioned to
spec. This is great information and something we can all learn from, in my
opinion, that is exactly what this list is for, knowledge. I know I will buy
the tool to check tension and it will be part of my frequent check list
until I determine there is no need to check it quite as frequently. That
should eliminate one possible problem and if I should ever "auger in" you
can bet it will not be loose cables or exceeding design limits, you can take
that to the bank. Without the recent discussions I would have probably
twanged the cables and let it go at that, obviously I have changed my mind.
To Bill of Georgia: Thanks!
Regards:
Clyde Barcus
----- Original Message -----
From: "Juan Vega" <amyvega2005@earthlink.net>
Sent: Monday, November 24, 2008 3:19 PM
Subject: Re: Zenith-List: Spreading fear about the XL
>
> Dirk,
> pull up the archives, i brought up the issue of VNE and Max manauvering
> speeds over one year ago, but the back room engineers ignored it.
>
> Fly it and follow the specs. My guess is the guys flying and that augered
> in ignored the flight envelope of the aircraft. BUILD IT TO PLANS AND FLY
> IT TO SPECS.
>
> Time to move on folks,
>
> Juan
>
> -----Original Message-----
>>From: Dirk Zahtilla <ideaz1@sbcglobal.net>
>>Sent: Nov 24, 2008 10:56 AM
>>To: zenith-list@matronics.com
>>Subject: Re: Zenith-List: Spreading fear about the XL
>>
>>You forgot the 640 which also has unbalanced ailerons HOWEVER... it has
>>push-pull tubes instead of cables and boxed wing spars (more related to
>>the load carying capacity).The margin between cruise and VNE is much
>>closer than the XL design. Maybe we need to look at this!? As I look at
>>the designs, they become capable of increasingly high cruise speeds and
>>with builders putting more h.p. in it becomes very easy to reach VNE very
>>quickly by entering even a very shallow dive. (also the rudder on the
>>6,7,&8 series ARE balanced, note the portion of the rudder ahead of the
>>hinge points...this is aerodynamic balance as opposed to weight balance).
>>
>>I think that what we are seeing is two groups of builders here: one group
>>who builds and fly's well within the specs of the design, and one group
>>that wants to achieve everything to the edge of the envelope and perhaps a
>>bit beyond. One group is made of builder/flyers, and one group is made of
>>experimenter builders/test pilots. This latter group will always push
>>aircraft design firms to re-examine their designs and hopefully this will
>>benefit the first group who will end up flying increasingly safe and more
>>capable aircraft.
>>
>>I'm sure that no-one on this list means to offend the builder/flyer group,
>>I know I don't. We are just part of the group that reaches out to extend
>>our potential.
>>
>>I am building a 601XL (which I may re-designate as
>>601XLA(airobat)orM(modified) just to make it clear that it is not totally
>>to plans) As I have said before I will use push-pull tubes for the
>>ailerons and elevator and balance both as well. The ailerons will move the
>>hingepoint rearward and the elevator will use weights in the tips which
>>will be attached to the elevator instead of the horizontal stab. I will
>>also use a boxed spar in the wing that meets at the center instead of
>>bolting on at the outer part of the fuselage.
>>
>>Dirk Z
>> ----- Original Message -----
>> From: jaybannist@cs.com
>> To: zenith-list@matronics.com
>> Sent: Monday, November 24, 2008 5:11 AM
>> Subject: Re: Zenith-List: Spreading fear about the XL
>>
>>
>> Roger.
>>
>> Your A&P did not design the 601HDS. How could he possibly know that
>> "this could lead to aileron flutter"? Chris Heintz designed the CH200,
>> CH601, CH601HD, CH601HDS, CH601XL, CH701, CH801 and CH750, all without
>> aileron balance. The rudder and elevators are not balanced either.
>> Control surface flutter is a MAJOR concern of all aircraft designers. If
>> he thought his control surface designs could lead to flutter, don't you
>> think he would have included some sort of balance?
>>
>> Exactly how many of these designs (PROPERLY constructed, flown and
>> maintained) has experienced VERIFIED aileron flutter?
>>
>> If you don't trust Chris Heintz, stay away from Chris Heinz designed
>> airplanes. Otherwise, COOL IT!
>>
>> Jay in Dallas
>> Do not archive
>>
>>
>>
>>
>>
>> -----Original Message-----
>> From: Roger & Lina Hill <hills@sunflower.com>
>> To: zenith-list@matronics.com
>> Sent: Sun, 23 Nov 2008 8:50 pm
>> Subject: RE: Zenith-List: Spreading fear about the XL
>>
>>
>> Howdy all;
>>
>> My A&P was looking over my 601HDS and commented that the ailerons were
>> not counterbalanced. He said this can lead to aileron flutter. My
>> Sonerai had
>> balanced ailerons, can someone comment on if the 601XL has balanced
>> ailerons and if not, could this result in wing flutter?
>>
>> Roger
>>
>>
>>
>>
>>------------------------------------------------------------------------------
>>
>> From: owner-zenith-list-server@matronics.com
>> [mailto:owner-zenith-list-server@matronics.com] On Behalf Of Jeff
>> Sent: Sunday, November 23, 2008 11:13 AM
>> To: zenith-list@matronics.com
>> Subject: Zenith-List: Spreading fear about the XL
>>
>> Friends, neighbors, and fellow Zenith Enthusiasts,
>>
>> I have received multiple off-list communications about the
>> unexplained XL crashes. We now have folks not part of the Zenith
>> community spreading "information" about the accidents. As I reported on
>> this list then, a group of LSA competitors advanced negative information
>> about the XL in person at the September 2007 Zenith Gathering in
>> Winchester, Virginia. For my part, I have not heard anything conclusive
>> from the entities looking at the design, including the Zenith Builder's
>> Analysis Group, Zenith, the NTSB, and European Governments, with two
>> exceptions. One is the cable tension advisory and the other is the
>> European action. Neither tells us what is happening unless you believe
>> that insufficient cable tension is the proper explanation. Others have
>> failed to find any design problem despite an extensive review. ZAC
>> conducted a second static load test with acceptable results. But the
>> impact of all the discussion is becoming clear. In the Second November
>> Is!
> sue, 2008 of Trade-A-Plane, there are three kits for sale and a completed
> aircraft. See page 87. Some advertisements have appeared on this list.
> Locally, some builders are making the decision to stop work on their
> projects. While all losses of human life are mourned without reservation,
> especially losses that need not occur, I believe that we all seek a
> rational explanation for these events if one exists, not speculation about
> what the facts we know might mean.
>>
>> So let me call on ZAC, the NTSB, the ZBAG, and all other
>> investigators with the standing to make valid conclusions, to report
>> whatever they have found or not found at this time in order to limit the
>> fear of the 601 XL that is currently spreading through the community.
>> They must speak up now before more damage based on fear is done to our
>> community.
>>
>> Please correct me if anyone with standing has provided a
>> full explanation of the events that are causing these concerns about the
>> XL.
>>
>> Jeff Davidson
>>
>>
>>
>> http://www.matronics.com/contribution< pre>
>>
>>------------------------------------------------------------------------------
>> Email message sent from CompuServe - visit us today at http://www.cs.com
>>
>>
>>
>
>
>
Message 25
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| Subject: | Re: One more in the air |
Andy-
Remember the old cartoons in Mad Magazine? Two thumbs, and two toes
up!
(Was that Don Martin, or was Don Martin the guy in Get Smart?)
Bill
----- Original Message -----
From: Dr. Andrew Elliott
To: Zenith-List Digest Server
Sent: Monday, November 24, 2008 10:43 AM
Subject: Zenith-List: One more in the air
Gang:
I am happy to report that N601GE, a Zodiac 601XL/TD, powered by a 3100
Corvair, took to the skies this morning for the first time at KFFZ,
Mesa, AZ. 0.7 hours, no engine problems.
Horizontal stabilizer likely needs some incidence adjustment, as full
aft trim was needed at 100 MIAS and left arm below that. Otherwise no
airframe problems.
More to report as flight testing continues...
Andy Elliott, Mesa, AZ
Message 26
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| Subject: | Re: Spreading fear about the XL. |
Hello Dirk,
-
You forgot to mention at least two other-groups:-
The "Armchair Experts".- They will never build or fly one.-A real big g
roup maybe mayority
-:-)- :-)
The "Bad Mouths"-- Also neither builder pilots of this airplane, but sp
ecially paid by competitors to keep people scared :-(- :-(
-
Saludos
Gary Gower
601 XL- Jab 3300- Builder.
710- STOL 912S- 230 hrs of FUN flying.
PLEASE Do not archive.
--- On Mon, 11/24/08, Dirk Zahtilla <ideaz1@sbcglobal.net> wrote:
From: Dirk Zahtilla <ideaz1@sbcglobal.net>
Subject: Re: Zenith-List: Spreading fear about the XL
You forgot the 640 which also has unbalanced ailerons HOWEVER... it has pus
h-pull tubes instead of cables and boxed wing spars (more related to the lo
ad carying capacity).The margin between cruise and VNE-is much closer tha
n the XL design. Maybe we need to look at this!?-As I look at the designs
, they become capable of increasingly high cruise speeds and with builders
putting more h.p. in it becomes very easy to reach VNE very quickly by ente
ring even a very shallow dive. (also the rudder on the 6,7,&8 series ARE ba
lanced, note the portion of the rudder ahead of the hinge points...this is
aerodynamic balance as opposed to weight balance).
-
I think that what we are seeing is two groups of builders here: one group w
ho builds and fly's well-within the specs of the design, and one group th
at wants to achieve everything to the edge of the envelope and perhaps a bi
t beyond. One group is made of builder/flyers, and one group is made of exp
erimenter builders/test pilots. This latter group will always push aircraft
design firms to re-examine their designs and hopefully this will benefit t
he first group who will end up flying-increasingly safe and more capable
aircraft.-
-
I'm sure that no-one on this list means to offend the builder/flyer group,
I know I don't. We are just part of the group that reaches out to extend ou
r potential.
-
I am building a 601XL (which I may re-designate as 601XLA(airobat)orM(modif
ied) just to make it clear that it is not totally to plans) As I have said
before I will use push-pull tubes for the ailerons and elevator and balance
both as well. The ailerons will move the hingepoint rearward and the eleva
tor will use weights in the tips which will be attached to the elevator ins
tead of the horizontal stab. I will also use a boxed spar in the wing that
meets at the center instead of bolting on at the outer part of the fuselage
.
-
Dirk Z
----- Original Message -----
From: jaybannist@cs.com
Sent: Monday, November 24, 2008 5:11 AM
Subject: Re: Zenith-List: Spreading fear about the XL
Roger.-
Your A&P did not design the 601HDS.- How could he possibly know that "thi
s could lead to aileron flutter"?- Chris Heintz designed the CH200, CH601
, CH601HD, CH601HDS, CH601XL, CH701, CH801 and CH750, all without aileron b
alance. The rudder and elevators are not balanced either. Control surface f
lutter is a MAJOR concern of all aircraft designers. If he thought his cont
rol surface designs could lead to flutter, don't you think he would have in
cluded some sort of balance?
Exactly how many of these designs (PROPERLY constructed, flown and maintain
ed) has experienced VERIFIED aileron flutter?
If you don't trust Chris Heintz, stay away from Chris Heinz designed airpla
nes. Otherwise, COOL IT!
Jay in Dallas
Do not archive
-----Original Message-----
From: Roger & Lina Hill <hills@sunflower.com>
Sent: Sun, 23 Nov 2008 8:50 pm
Subject: RE: Zenith-List: Spreading fear about the XL
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Howdy all;
-
My A&P was looking over my 601HDS and commented that the ailerons were not
counterbalanced.- He said this can lead to aileron flutter.- My Sonerai
had
balanced ailerons, can someone comment on if the 601XL has balanced aileron
s and if not, could this result in wing flutter?
-
Roger
-
-
-
From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-serv
er@matronics.com] On Behalf Of Jeff
Sent: Sunday, November 23, 2008 11:13 AM
Subject: Zenith-List: Spreading fear about the XL
-
Friends, neighbors, and fellow Zenith Enthusiasts,
-----------
----------- I have received multiple off-list communi
cations about the unexplained XL crashes.- We now have folks not part of
the Zenith community spreading "information" about the accidents.- As I r
eported on this list then, a group of LSA competitors advanced negative inf
ormation about the XL in person at the September 2007 Zenith Gathering in W
inchester, Virginia.- For my part, I have not heard anything conclusive f
rom the entities looking at the design, including the Zenith Builder's Anal
ysis Group, Zenith, the NTSB, and European Governments, with two exceptions
.- One is the cable tension advisory and the other is the European action
.- Neither tells us what is happening unless you believe that insufficien
t cable tension is the proper explanation.- Others have failed to find an
y design problem despite an extensive review.- ZAC conducted a second sta
tic load test with acceptable results.- But the impact of all the discuss
ion is
becoming clear.- In the Second November Issue, 2008 of Trade-A-Plane, th
ere are three kits for sale and a completed aircraft.- See page 87. -So
me advertisements have appeared on this list. -Locally, some builders are
making the decision to stop work on their projects.- While all losses of
human life are mourned without reservation, especially losses that need no
t occur, I believe that we all seek a rational explanation for these events
if one exists, not speculation about what the facts we know might mean.-
-
----------- So let me call on ZAC, the NTSB, the ZBAG
, and all other investigators with the standing to make valid conclusions,
to report whatever they have found or not found at this time in order to li
mit the fear of the 601 XL that is currently spreading through the communit
y.- They must speak up now before more damage based on fear is done to ou
r community.
-
----------- Please correct me if anyone with standing
has provided a full explanation of the events that are causing these conce
rns about the XL.
-
Jeff Davidson
-
-
- ----http://www.matronics.com/contribution< pre>
Email message sent from CompuServe - visit us today at http://www.cs.com
href="http://www.matronics.com/contribution">http://www.matronics.com/chr
ef="http://www.matronics.com/Navigator?Zenith-List">http://www.matronhref
="http://forums.matronics.com">http://forums.matronics.com
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| Subject: | Re: One more in the air |
Andy
Congratulations from another Corvair/Zodiac builder who is green with envy.
Dan Dempsey
(do not archive)
--------
Scratch building XL with Corvair Engine
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=216129#216129
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| Subject: | One more in the air |
Don Martin - Mad
Don Adams - Get Smart
-- Craig "Don" Payne
Do not archive
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of Bill Naumuk
Sent: Monday, November 24, 2008 4:52 PM
Subject: Re: Zenith-List: One more in the air
Andy-
Remember the old cartoons in Mad Magazine? Two thumbs, and two toes up!
(Was that Don Martin, or was Don Martin the guy in Get Smart?)
Bill
----- Original Message -----
From: Dr. Andrew Elliott <mailto:a.s.elliott@cox.net>
Sent: Monday, November 24, 2008 10:43 AM
Subject: Zenith-List: One more in the air
Gang:
I am happy to report that N601GE, a Zodiac 601XL/TD, powered by a 3100
Corvair, took to the skies this morning for the first time at KFFZ, Mesa,
AZ. 0.7 hours, no engine problems.
Horizontal stabilizer likely needs some incidence adjustment, as full aft
trim was needed at 100 MIAS and left arm below that. Otherwise no airframe
problems.
More to report as flight testing continues...
Andy Elliott, Mesa, AZ
href="http://www.matronics.com/contribution">http://www.matronics.com/chref
"http://www.matronics.com/Navigator?Zenith-List">http://www.matronhref="http
://forums.matronics.com">http://forums.matronics.com
Message 29
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| Subject: | Re: Spreading fear about the XL |
On Mon, Nov 24, 2008 at 09:46:48AM -0800, Rick Lindstrom wrote:
> Unless we need to stress the airframe for aerobatics, or are given to
> rapid control inputs, or plan on significantly higher cruise airspeeds
> beyond what the airframe was designed for, I think we can have some level
> of confidence in the design as it is when flown and maintained as
> specified by Zenith.
This is pretty much my take on the matter, as well...though the one
AMD-built aircraft does give me pause. Until we find a smoking gun, I'm
going to be vigilant about maintaining my airplane to all manufacturer's
specifications and making sure never to subject it to maneuvers or speeds
that have any risk of departing the recommended and designed flight
envelope.
> Overall, I think these kinds of discussion are generally positive, as long
> as we don't succumb to wild speculation and give in to the temptation to
> "fix" something that may not even be a factor. Like everyone else, I look
> forward to the day when we can positively identify the smoking gun (if
> there even is one).
I'm confident one will be found, if not as quickly as we would like. I'm not
going to let it get in the way of me enjoying my airplane.
--
Jay Maynard, K5ZC, PP-ASEL http://www.conmicro.com
http://jmaynard.livejournal.com http://www.tronguy.net
Fairmont, MN (KFRM) (Yes, that's me!)
AMD Zodiac CH601XLi N55ZC http://www.tronguy.net/N55ZC.shtml
Message 30
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| Subject: | Re: One more in the air |
Don Martin, definitely: http://www.donmartinshrine.com/
Carlos
do not archive
2008/11/24 Bill Naumuk <naumuk@alltel.net>
> Andy-
> Remember the old cartoons in Mad Magazine? Two thumbs, and two toes up!
> (Was that Don Martin, or was Don Martin the guy in Get Smart?)
> Bill
>
>
Message 31
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| Subject: | Re: One more in the air |
Gotcha-
do not archive
----- Original Message -----
From: Craig Payne
To: zenith-list@matronics.com
Sent: Monday, November 24, 2008 7:02 PM
Subject: RE: Zenith-List: One more in the air
Don Martin - Mad
Don Adams - Get Smart
-- Craig "Don" Payne
Do not archive
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of Bill Naumuk
Sent: Monday, November 24, 2008 4:52 PM
To: zenith-list@matronics.com
Subject: Re: Zenith-List: One more in the air
Andy-
Remember the old cartoons in Mad Magazine? Two thumbs, and two
toes up!
(Was that Don Martin, or was Don Martin the guy in Get Smart?)
Bill
----- Original Message -----
From: Dr. Andrew Elliott
To: Zenith-List Digest Server
Sent: Monday, November 24, 2008 10:43 AM
Subject: Zenith-List: One more in the air
Gang:
I am happy to report that N601GE, a Zodiac 601XL/TD, powered by a
3100 Corvair, took to the skies this morning for the first time at KFFZ,
Mesa, AZ. 0.7 hours, no engine problems.
Horizontal stabilizer likely needs some incidence adjustment, as
full aft trim was needed at 100 MIAS and left arm below that. Otherwise
no airframe problems.
More to report as flight testing continues...
Andy Elliott, Mesa, AZ
href="http://www.matronics.com/contribution">http://www.matronics.com/c
href="http://www.matronics.com/Navigator?Zenith-List">http://www.matron
href="http://forums.matronics.com">http://forums.matronics.com
http://www.matronics.com/contributionhttp://www.matronics.com/Navigator?Z
enith-Listhttp://forums.matronics.com
Message 32
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| Subject: | 601XL passenger seat and baggage shelf dimensions? |
I've volunteered my airplane for Animal Rescue Flights missions, to fly
animals in need of transportation. (Check them out at
http://aviation.meetup.com/95/ .) In order to let them know what to expect,
I need to know the dimensions of the passenger seat, and the baggage shelf,
of my Zodiac, so I can let them know how big a crate I can handle. Anyone
have the numbers handy, to save me a trip to the airport? Thanks.
--
Jay Maynard, K5ZC, PP-ASEL http://www.conmicro.com
http://jmaynard.livejournal.com http://www.tronguy.net
Fairmont, MN (KFRM) (Yes, that's me!)
AMD Zodiac CH601XLi N55ZC http://www.tronguy.net/N55ZC.shtml
Message 33
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| Subject: | Re: One more in the air |
Congrats to you doc...
do not archive
Ben Haas
N801BH
www.haaspowerair.com
-- "Dr. Andrew Elliott" <a.s.elliott@cox.net> wrote:
Gang: I am happy to report that N601GE, a Zodiac 601XL/TD, powered by a
3100 Corvair, took to the skies this morning for the first time at KFFZ,
Mesa, AZ. 0.7 hours, no engine problems. Horizontal stabilizer likely
needs some incidence adjustment, as full aft trim was needed at 100 MIA
S and left arm below that. Otherwise no airframe problems. More to repo
rt as flight testing continues... Andy Elliott, Mesa, AZ
========================
========================
========================
========================
========================
____________________________________________________________
Love Graphic Design? Find a school near you. Click Now.
http://thirdpartyoffers.netzero.net/TGL2241/fc/PnY6ryAdIcOMPXYZoEzcXx2Pk
uyedvDe1WfZQkOthbjjnC9KQd2qu/
Message 34
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| Subject: | Re: Spreading fear about the XL |
The incident happened at 103 hours, but prior to the first annual. Before the
first flight, as a courtesy, the AMD fellows flew up from Eastman, inspected
the plane, tested the cables, W&B, control travel, etc., and looked over the
whole thing for a couple hours. Proclaimed it was safe and the AMD test pilot,
John Begonias (sp) flew it first. I expect the cables were correct before he
flew because I saw them test them. I did not test them between first flight and
the incident simply because I did not know I should. After the incident I
inspected every rivet, bolt and joint and tightened the cables, but I did not
have a tensionometer and in fact I don't remember if I knew then what the correct
setting should have been. When I checked the tension last week after reading
the AMD letter and buying a tenisonometer the aileron cables were at 17
pounds. They are set correctly now. Best regards, Bill
**************
One site has it
all. Your email accounts, your social networks, and the things you love. Try
the new AOL.com
mlcntaolcom00000001)
Message 35
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| Subject: | Spreading fear about the XL |
Howdy all;
Gee, it looks like I took a smoke in a fireworks factory!!!
I too am an engineer, but just not an aircraft engineer, still I do know a
thing or two about harmonic oscillations, almost enough to be dangerous!!! I
also studied flight control designs in grad school, but never put it to good
use.
I should clear up a couple of thing, my 601 HDS does have push rods to the
ailerons, so the design does differ from the newer 601XL. I note this
because apparently the older models have not had any flutter issues, well
none that I know about anyway.
Also, my A&Ps father died flying his Michel flying wing, something he built
25 years earlier. This plane was registered experimental, and had a wood
structure. Over the years, fuel leaked from the tanks and weakened the glue
holding the wing D-box structure together. This caused it to fail at 200
feet AGL, right in the pattern at the airport. Worse, it was right in front
of his buddies. Of course, we don't have to worry about this with our
planes, one less worry. Inspecting the D-box was out of the question
without special tools, this section was covered by fabric and ply wood.
I once had my aileron push rod detach on my RC plane, if that matters. It
buzzed in the wind, but perhaps because of the low cruise speed of the
aircraft, it had no other detrimental effects other than to add drag to one
wing. I think the airspeed, oscillation frequency and magnitude of the
oscillations when the flutter occurs has a direct relationship to the damage
potential to the wing. Some flutter at low speeds seem to be completely
tolerable as in my experience, but I suspect that as airspeeds increase, so
does the damage potential if flutter does occur.
Roger
-----Original Message-----
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of Rick Lindstrom
Sent: Monday, November 24, 2008 11:47 AM
Subject: Re: Zenith-List: Spreading fear about the XL
In this latest discussion, we're all operating on the speculation that the
cause of the handful of wing fold accidents in the 601 have their initial
cause in aileron flutter (a believable hypothesis, given the current lack of
any other concrete data). Flutter at high speeds can destroy an airframe
structure in seconds, and it's pretty easy to imagine a fluttering aileron
might overstress the rear spar/fuselage attach point to failure, allowing
the wing to twist until the lower main spar attachment surrenders, and the
wind folds up and over. Not a pretty scenario.
Some have suggested that balancing the ailerons is the cure. And I remember
a recent YouTube video showing exactly this modification to some Brazilian
601 airframes, which also sported some other significant modifications. Push
pull tubes would also firm up the play in the aileron control system. That's
the beauty of an experimental aircraft. As the manufacturer of record, we
can do these things legally. But legal isn't always safe, and any departures
from what the kit manufacturer has designed should be done with extreme care
and be thoroughly tested. To Zenith's credit, they've been very approachable
when submitting concepts for improvements or changes.
But the fact remains that the flight control surfaces are not going to
flutter if the cable tensions are anywhere near proper specification. We can
add weight and complexity as added insurance (and to make ourselves feel
better), but I think it's good idea every now and then to take a deep breath
and consider how we fly the airplane as well.
Unless we need to stress the airframe for aerobatics, or are given to rapid
control inputs, or plan on significantly higher cruise airspeeds beyond
what the airframe was designed for, I think we can have some level of
confidence in the design as it is when flown and maintained as specified by
Zenith. Sure, I'd like to hear more from Zenith about what's been found in
their collaboration with the NTSB so far, but I also understand the
restrictions in divulging information prematurely that they must adhere to.
Overall, I think these kinds of discussion are generally positive, as long
as we don't succumb to wild speculation and give in to the temptation to
"fix" something that may not even be a factor. Like everyone else, I look
forward to the day when we can positively identify the smoking gun (if there
even is one).
-----Original Message-----
>From: Dirk Zahtilla <ideaz1@sbcglobal.net>
>Sent: Nov 24, 2008 8:14 AM
>To: zenith-list@matronics.com
>Subject: Re: Zenith-List: Spreading fear about the XL
>
>Just another comment. Sorry Jay, I truly mean no offense. It is not our
guess or an A/Ps opinion that balancing control surfaces reduces the
possibility of flutter. It's a proven condition of aerodynamics. If not, I'm
sure NOBODY would put lead weights in their ailerons' leading edges. While I
build I also own and fly a Cessna 150 with weight balanced ailerons. It's
cruise speed is just a bit more than some older designs at about 105mph
without balance weights but the VNE is 160mph. This is a Much larger ratio
than the 601 and I don't think it would meet the certification requirements
at that speed without balanced surfaces(the elevator is balanced as well and
also the rudder).
>Dirk
>
> ----- Original Message -----
> From: jaybannist@cs.com
> To: zenith-list@matronics.com
> Sent: Monday, November 24, 2008 7:43 AM
> Subject: Re: Zenith-List: Spreading fear about the XL
>
>
> Roger,
>
> Not to be argumentative, but I am 74 years old and I practiced
architecture for more than 45 years. So I know a LOT about building design.
That does not qualify me to judge the functional or structural integrity of
another architect's design without knowing the details of the criteria, the
specific goals for the design, and the logic of the design solution. I have
plenty of prejudices when it comes to the practice of architecture; but I
recognize them a such and refrain from publicly condemning others who do not
share my philosophy.
>
> Stating that "ANY unbalanced aileron, regardless of make and model,
would be more likely to flutter and that balancing them could reduce or even
avoid the possibility of flutter" is a prejudiced statement and it is
simply not true. Flutter potential of any control surface is determined by
the totality of the design: size, shape, weight, weight distribution, pivot
location, control system, design speed and so forth and so on. If the
designer makes the right choices (which might compromise other parts of the
design) he can provide a control surface that will not flutter, period.
However, many examples prove that most designers are not willing to
compromise other parts of the airframe to provide a flutter-free control
surface. The fallback is to provide a20design work-around in the form of
balance weights or aerodynamic balancing surfaces. That is not to criticize
the use of balancing. It is simply a matter of choice. Chris Heintz chose
to provide control surfaces that do not need balancing when operated within
the stated operating limits. If you exceed those limits, you are on your
own and in dangerous territory - "outside the envelope". That is true of
any aircraft and it is where failures occur, including control surface
flutter, wing failure and who knows what.
>
> I'll say it again: If you don't trust the designer, don't fly the
airplanes he has designed. And don't try to "tweek" his design when you
don't know why and how it was designed the way it is.
>
> 'Nuff said - Jay in Dallas
> Do not archive
>
>
> -----Original Message-----
> From: Roger & Lina Hill <hills@sunflower.com>
> To: zenith-list@matronics.com
> Sent: Mon, 24 Nov 2008 8:11 am
> Subject: RE: Zenith-List: Spreading fear about the XL
>
>
> Jay;
>
> To be more exact, I believe his point was that ANY unbalanced aileron,
regardless of make and model, would be more likely to flutter and that
balancing them could reduce or even avoid the possibility of flutter. As
for not designing the 601, I don't think it is necessary to design something
in order to understand it. My A&P is about 70 years old, his dad was an A&P
as well, so I think he could know through a combination of training and
experience. He is also a homebuilder and so was his father, who
unfortunately died when his homebuilt wing failed in flight a few years ago.
>
> Roger
>
>
>---------------------------------------------------------------------------
---
>
> From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of
jaybannist@cs.com
> Sent: Monday, November 24, 2008 7:11 AM
> To: zenith-list@matronics.com
> Subject: Re: Zenith-List: Spreading fear about the XL
>
> Roger.
>
> Your A&P did not design the 601HDS. How could he possibly know t hat
"this could lead to aileron flutter"? Chris Heintz designed the CH200,
CH601, CH601HD, CH601HDS, CH601XL, CH701, CH801 and CH750, all without
aileron balance. The rudder and elevators are not balanced either. Control
surface flutter is a MAJOR concern of all aircraft designers. If he thought
his control surface designs could lead to flutter, don't you think he would
have included some sort of balance?
>
> Exactly how many of these designs (PROPERLY constructed, flown and
maintained) has experienced VERIFIED aileron flutter?
>
> If you don't trust Chris Heintz, stay away from Chris Heinz designed
airplanes. Otherwise, COOL IT!
>
> Jay in Dallas
> Do not archive
>
>
> -----Original Message-----
> From: Roger & Lina Hill <hills@sunflower.com>
> To: zenith-list@matronics.com
> Sent: Sun, 23 Nov 2008 8:50 pm
> Subject: RE: Zenith-List: Spreading fear about the XL
> Howdy all;
>
> My A&P was looking over my 601HDS and commented that the ailerons were
not counterbalanced. He said this can lead to aileron flutter. My Sonerai
had
> balanced ailerons, can someone comment on if the 601XL has balanced
ailerons and if not, could this result in wing flutter?
>
> Roger
>
> &n bsp;
>
>
>---------------------------------------------------------------------------
---
>
> From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of Jeff
> Sent: Sunday, November 23, 2008 11:13 AM
> To: zenith-list@matronics.com
> Subject: Zenith-List: Spreading fear about the XL
>
> Friends, neighbors, and fellow Zenith Enthusiasts,
>
> I have received multiple off-list communications about the
unexplained XL crashes. We now have folks not part of the Zenith community
spreading "information" about the accidents. As I reported on this list
then, a group of LSA competitors advanced negative information about the XL
in person at the September 2007 Zenith Gathering in Winchester, Virginia.
For my part, I have not heard anything conclusive from the entities looking
at the design, including the Zenith Builder's Analysis Group, Zenith, the
NTSB, and European Governments, with two exceptions. One is the cable
tension advisory and the other is the European action. Neither tells us
what is happening unless you believe that insufficient cable tension is the
proper explanation. Others have failed to find any design problem despite
an extensive review. ZAC conducted a second static load test with
acceptable results. But the impact of all the discussion is becoming clear.
In the Second November Issue, 2008 of Trade-A-Plane, there are three
kits20for sale and a completed aircraft. See page 87. Some advertisements
have appeared on this list. Locally, some builders are making the decision
to stop work on their projects. While all losses of human life are mourned
without reservation, especially losses that need not occur, I believe that
we all seek a rational explanation for these events if one exists, not
speculation about what the facts we know might mean.
>
> So let me call on ZAC, the NTSB, the ZBAG, and all other
investigators with the standing to make valid conclusions, to report
whatever they have found or not found at this time in order to limit the
fear of the 601 XL that is currently spreading through the community. They
must speak up now before more damage based on fear is done to our community.
>
> Please correct me if anyone with standing has provided a
full20explanation of the events that are causing these concerns about the
XL.
>
> Jeff Davidson
>
>
>
> http://www.matronics.com/contribution< pre>
>
>---------------------------------------------------------------------------
---
> size=2 width="100%" align=center>
> Email message sent from CompuServe - visit us today at http://www.cs.com
>
http://www.matronics.com/contributionhttp://www.matronics.com/Navigator?Zeni
th-Listhttp://forums.matronics.com
>
>=================
>=================
>ution">http://www.matronics.com/contribution
>or?Zenith-List">http://www.matronics.com/Navigator?Zenith-List
>ilable via the Web Forums!
>p://forums.matronics.com
>
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| Subject: | Our 701 in the local AirShow. Flyers Guadalajara Vuela. |
Hello Friends:
-
This last week end we had lots of FUN!- we had the CHANCE to-fly at our
local Air Show!-
-
The great thing for us, was that Cap. Rogelio Mu=F1oz (Director of the Airs
how)- ordered to build a-"custom made temporary registred"-airstrip f
or Ultralights and Radio Controled airplanes...--
-
The show was at--the Cajititlan Lake shore.- We had the chance to Dem
o the 701 STOL in front of more than 100,000 people (in a two day fair).-
- WE made several flights, two as demo flights each day and several other
s to keep people happy betwen performers.-
-
This is a link to the first- video I found about the Aishow,- from some
one (?)-that was there,-
-
The video (with our 701) is at the bottom of this page (the last one that s
tarts with a guy in front of a Police Chopper).
-
Hope you enjoy- We realy DID!!!!
-
http://faroviejo.com.mx/2008/11/nuestro-paseo-en-el-festival-de-la-aviacion
-flyers-2008-en-cajititlan-jalisco/
-
Or this tiny link:-
-
http://tinyurl.com/5se97s
-
Saludos
Gary Gower.
Flying from Chapala, Mexico- (This week end in Cajititlan lake Flyers 200
8 Airshow).
=0A=0A=0A
Message 37
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| Subject: | Spreading fear about the XL |
Hi, Roger.
I don't think anyone here thinks you're "smoking in a fireworks factory", it's
just that all the conjecture and speculation on this issue has created a rather
large sore spot among those of us who own and fly the 601XL. There have been
a ton of posts with headers like "601 Wing Failure" and "Another Zenith 601 Crash"
that have only served to fan the flames of fear of the design and impugn
the company behind it. So far, the efforts of the NTSB, Zenith Aircraft, and
even the ZBAG group have turned up little in terms of a common causal factor in
these crashes. The only thing that we all share is frustration, those who have
lost loved ones are understandably angry that such a thing could happen, and
those of us who continue to fly the 601 series want to have confidence that
there will be no more human tragedies.
I'm fortunate not to have encountered flutter personally in my 4,500+ PIC hours
so far, but I've recently seen in-flight video of elevator flutter in action
on a Piper that scared the hell out of me. I didn't know a tail structure could
take that sort of abuse and still hold together. And I think of that video every
time I go flying.
Fortunately, there are many factors that we can control - cable tensions, rigging,
airspeeds, and ongoing airframe integrity. This doesn't replace knowing the
exact cause of the wing fold crashes, but it does give me enough peace of mind
to not live in fear and continue to enjoy the airplane.
Rick
-----Original Message-----
>From: Roger & Lina Hill <hills@sunflower.com>
>Sent: Nov 24, 2008 8:55 PM
>To: zenith-list@matronics.com
>Subject: RE: Zenith-List: Spreading fear about the XL
>
>
>
>Howdy all;
>
>Gee, it looks like I took a smoke in a fireworks factory!!!
>
>I too am an engineer, but just not an aircraft engineer, still I do know a
>thing or two about harmonic oscillations, almost enough to be dangerous!!! I
>also studied flight control designs in grad school, but never put it to good
>use.
>
>I should clear up a couple of thing, my 601 HDS does have push rods to the
>ailerons, so the design does differ from the newer 601XL. I note this
>because apparently the older models have not had any flutter issues, well
>none that I know about anyway.
>
>Also, my A&Ps father died flying his Michel flying wing, something he built
>25 years earlier. This plane was registered experimental, and had a wood
>structure. Over the years, fuel leaked from the tanks and weakened the glue
>holding the wing D-box structure together. This caused it to fail at 200
>feet AGL, right in the pattern at the airport. Worse, it was right in front
>of his buddies. Of course, we don't have to worry about this with our
>planes, one less worry. Inspecting the D-box was out of the question
>without special tools, this section was covered by fabric and ply wood.
>
>I once had my aileron push rod detach on my RC plane, if that matters. It
>buzzed in the wind, but perhaps because of the low cruise speed of the
>aircraft, it had no other detrimental effects other than to add drag to one
>wing. I think the airspeed, oscillation frequency and magnitude of the
>oscillations when the flutter occurs has a direct relationship to the damage
>potential to the wing. Some flutter at low speeds seem to be completely
>tolerable as in my experience, but I suspect that as airspeeds increase, so
>does the damage potential if flutter does occur.
>
>Roger
>
>
>-----Original Message-----
>From: owner-zenith-list-server@matronics.com
>[mailto:owner-zenith-list-server@matronics.com] On Behalf Of Rick Lindstrom
>Sent: Monday, November 24, 2008 11:47 AM
>To: zenith-list@matronics.com
>Subject: Re: Zenith-List: Spreading fear about the XL
>
>
>In this latest discussion, we're all operating on the speculation that the
>cause of the handful of wing fold accidents in the 601 have their initial
>cause in aileron flutter (a believable hypothesis, given the current lack of
>any other concrete data). Flutter at high speeds can destroy an airframe
>structure in seconds, and it's pretty easy to imagine a fluttering aileron
>might overstress the rear spar/fuselage attach point to failure, allowing
>the wing to twist until the lower main spar attachment surrenders, and the
>wind folds up and over. Not a pretty scenario.
>
>Some have suggested that balancing the ailerons is the cure. And I remember
>a recent YouTube video showing exactly this modification to some Brazilian
>601 airframes, which also sported some other significant modifications. Push
>pull tubes would also firm up the play in the aileron control system. That's
>the beauty of an experimental aircraft. As the manufacturer of record, we
>can do these things legally. But legal isn't always safe, and any departures
>from what the kit manufacturer has designed should be done with extreme care
>and be thoroughly tested. To Zenith's credit, they've been very approachable
>when submitting concepts for improvements or changes.
>
>But the fact remains that the flight control surfaces are not going to
>flutter if the cable tensions are anywhere near proper specification. We can
>add weight and complexity as added insurance (and to make ourselves feel
>better), but I think it's good idea every now and then to take a deep breath
>and consider how we fly the airplane as well.
>
>Unless we need to stress the airframe for aerobatics, or are given to rapid
>control inputs, or plan on significantly higher cruise airspeeds beyond
>what the airframe was designed for, I think we can have some level of
>confidence in the design as it is when flown and maintained as specified by
>Zenith. Sure, I'd like to hear more from Zenith about what's been found in
>their collaboration with the NTSB so far, but I also understand the
>restrictions in divulging information prematurely that they must adhere to.
>
>Overall, I think these kinds of discussion are generally positive, as long
>as we don't succumb to wild speculation and give in to the temptation to
>"fix" something that may not even be a factor. Like everyone else, I look
>forward to the day when we can positively identify the smoking gun (if there
>even is one).
>
>-----Original Message-----
>>From: Dirk Zahtilla <ideaz1@sbcglobal.net>
>>Sent: Nov 24, 2008 8:14 AM
>>To: zenith-list@matronics.com
>>Subject: Re: Zenith-List: Spreading fear about the XL
>>
>>Just another comment. Sorry Jay, I truly mean no offense. It is not our
>guess or an A/Ps opinion that balancing control surfaces reduces the
>possibility of flutter. It's a proven condition of aerodynamics. If not, I'm
>sure NOBODY would put lead weights in their ailerons' leading edges. While I
>build I also own and fly a Cessna 150 with weight balanced ailerons. It's
>cruise speed is just a bit more than some older designs at about 105mph
>without balance weights but the VNE is 160mph. This is a Much larger ratio
>than the 601 and I don't think it would meet the certification requirements
>at that speed without balanced surfaces(the elevator is balanced as well and
>also the rudder).
>>Dirk
>>
>> ----- Original Message -----
>> From: jaybannist@cs.com
>> To: zenith-list@matronics.com
>> Sent: Monday, November 24, 2008 7:43 AM
>> Subject: Re: Zenith-List: Spreading fear about the XL
>>
>>
>> Roger,
>>
>> Not to be argumentative, but I am 74 years old and I practiced
>architecture for more than 45 years. So I know a LOT about building design.
>That does not qualify me to judge the functional or structural integrity of
>another architect's design without knowing the details of the criteria, the
>specific goals for the design, and the logic of the design solution. I have
>plenty of prejudices when it comes to the practice of architecture; but I
>recognize them a such and refrain from publicly condemning others who do not
>share my philosophy.
>>
>> Stating that "ANY unbalanced aileron, regardless of make and model,
>would be more likely to flutter and that balancing them could reduce or even
>avoid the possibility of flutter" is a prejudiced statement and it is
>simply not true. Flutter potential of any control surface is determined by
>the totality of the design: size, shape, weight, weight distribution, pivot
>location, control system, design speed and so forth and so on. If the
>designer makes the right choices (which might compromise other parts of the
>design) he can provide a control surface that will not flutter, period.
>However, many examples prove that most designers are not willing to
>compromise other parts of the airframe to provide a flutter-free control
>surface. The fallback is to provide a20design work-around in the form of
>balance weights or aerodynamic balancing surfaces. That is not to criticize
>the use of balancing. It is simply a matter of choice. Chris Heintz chose
>to provide control surfaces that do not need balancing when operated within
>the stated operating limits. If you exceed those limits, you are on your
>own and in dangerous territory - "outside the envelope". That is true of
>any aircraft and it is where failures occur, including control surface
>flutter, wing failure and who knows what.
>>
>> I'll say it again: If you don't trust the designer, don't fly the
>airplanes he has designed. And don't try to "tweek" his design when you
>don't know why and how it was designed the way it is.
>>
>> 'Nuff said - Jay in Dallas
>> Do not archive
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> -----Original Message-----
>> From: Roger & Lina Hill <hills@sunflower.com>
>> To: zenith-list@matronics.com
>> Sent: Mon, 24 Nov 2008 8:11 am
>> Subject: RE: Zenith-List: Spreading fear about the XL
>>
>>
>>
>> Jay;
>>
>> To be more exact, I believe his point was that ANY unbalanced aileron,
>regardless of make and model, would be more likely to flutter and that
>balancing them could reduce or even avoid the possibility of flutter. As
>for not designing the 601, I don't think it is necessary to design something
>in order to understand it. My A&P is about 70 years old, his dad was an A&P
>as well, so I think he could know through a combination of training and
>experience. He is also a homebuilder and so was his father, who
>unfortunately died when his homebuilt wing failed in flight a few years ago.
>
>>
>> Roger
>>
>>
>>
>>
>>---------------------------------------------------------------------------
>---
>>
>> From: owner-zenith-list-server@matronics.com
>[mailto:owner-zenith-list-server@matronics.com] On Behalf Of
>jaybannist@cs.com
>> Sent: Monday, November 24, 2008 7:11 AM
>> To: zenith-list@matronics.com
>> Subject: Re: Zenith-List: Spreading fear about the XL
>>
>> Roger.
>>
>> Your A&P did not design the 601HDS. How could he possibly know t hat
>"this could lead to aileron flutter"? Chris Heintz designed the CH200,
>CH601, CH601HD, CH601HDS, CH601XL, CH701, CH801 and CH750, all without
>aileron balance. The rudder and elevators are not balanced either. Control
>surface flutter is a MAJOR concern of all aircraft designers. If he thought
>his control surface designs could lead to flutter, don't you think he would
>have included some sort of balance?
>>
>> Exactly how many of these designs (PROPERLY constructed, flown and
>maintained) has experienced VERIFIED aileron flutter?
>>
>> If you don't trust Chris Heintz, stay away from Chris Heinz designed
>airplanes. Otherwise, COOL IT!
>>
>> Jay in Dallas
>> Do not archive
>>
>>
>> -----Original Message-----
>> From: Roger & Lina Hill <hills@sunflower.com>
>> To: zenith-list@matronics.com
>> Sent: Sun, 23 Nov 2008 8:50 pm
>> Subject: RE: Zenith-List: Spreading fear about the XL
>> Howdy all;
>>
>> My A&P was looking over my 601HDS and commented that the ailerons were
>not counterbalanced. He said this can lead to aileron flutter. My Sonerai
>had
>> balanced ailerons, can someone comment on if the 601XL has balanced
>ailerons and if not, could this result in wing flutter?
>>
>> Roger
>>
>> &n bsp;
>>
>>
>>---------------------------------------------------------------------------
>---
>>
>> From: owner-zenith-list-server@matronics.com
>[mailto:owner-zenith-list-server@matronics.com] On Behalf Of Jeff
>> Sent: Sunday, November 23, 2008 11:13 AM
>> To: zenith-list@matronics.com
>> Subject: Zenith-List: Spreading fear about the XL
>>
>> Friends, neighbors, and fellow Zenith Enthusiasts,
>>
>> I have received multiple off-list communications about the
>unexplained XL crashes. We now have folks not part of the Zenith community
>spreading "information" about the accidents. As I reported on this list
>then, a group of LSA competitors advanced negative information about the XL
>in person at the September 2007 Zenith Gathering in Winchester, Virginia.
>For my part, I have not heard anything conclusive from the entities looking
>at the design, including the Zenith Builder's Analysis Group, Zenith, the
>NTSB, and European Governments, with two exceptions. One is the cable
>tension advisory and the other is the European action. Neither tells us
>what is happening unless you believe that insufficient cable tension is the
>proper explanation. Others have failed to find any design problem despite
>an extensive review. ZAC conducted a second static load test with
>acceptable results. But the impact of all the discussion is becoming clear.
>In the Second November Issue, 2008 of Trade-A-Plane, there are three
>kits20for sale and a completed aircraft. See page 87. Some advertisements
>have appeared on this list. Locally, some builders are making the decision
>to stop work on their projects. While all losses of human life are mourned
>without reservation, especially losses that need not occur, I believe that
>we all seek a rational explanation for these events if one exists, not
>speculation about what the facts we know might mean.
>>
>> So let me call on ZAC, the NTSB, the ZBAG, and all other
>investigators with the standing to make valid conclusions, to report
>whatever they have found or not found at this time in order to limit the
>fear of the 601 XL that is currently spreading through the community. They
>must speak up now before more damage based on fear is done to our community.
>>
>> Please correct me if anyone with standing has provided a
>full20explanation of the events that are causing these concerns about the
>XL.
>>
>> Jeff Davidson
>>
>>
>>
>> http://www.matronics.com/contribution< pre>
>>
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| Subject: | Re: One more in the air |
Congratulations Andy.
do not archive
--------
Ron Lendon, Clinton Township, MI
WW Corvair with Roy's Garage 5th bearing
Zodiac XL, ScrapBuilder ;-)
http://www.mykitlog.com/rlendon
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=216162#216162
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| Subject: | My first week at FLAG |
I just wrapped up my first week building at my plane's
new home, First Light Aviation Group (FLAG) in
Livermore, CA. What a difference. When I was
building at home, I was always prone to distractions,
the phone, the computer, my wife, etc. This past week
building at FLAG, I got a lot more done, quicker and
easier. Besides being a dedicated work space, FLAG
has large tools that I'd never used before like a
break and shear. WOW, what a difference the right
tools make. I re-made the canopy front side covers
(6C3-6) five different times to get the fit right. At
home, this would have taken me at least an hour for
each one. Using the shear and brake cut the
fabrication time down to 6 minutes and they look so
much better. And having other builders there gives me
someone to bounce ideas off of. I wish I had started
my project at this facility, I'd be flying by now.
Northern California builders should check it out at:
www.flaglvk.com.
Rich Vetterli
601XL/Corvair
Checkout my progress at: www.geocities.com/stixx5a
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