Today's Message Index:
----------------------
1. 02:17 AM - Re: Manual trim (steveadams)
2. 02:36 AM - Re: Accident (steveadams)
3. 03:21 AM - Re: Accidents (David Downey)
4. 03:26 AM - Re: Re: Accident (David Downey)
5. 03:51 AM - Re: Manual trim (kmccune)
6. 04:40 AM - Re: Re: Accident (Jay Maynard)
7. 05:30 AM - Re: Accident (steveadams)
8. 05:30 AM - Re: Sign-on for structural analysis (John Kearney)
9. 05:32 AM - 701: Elevator Bellcrank Neutral? (Tony Bonsell)
10. 05:40 AM - Re: Armchair Engineer (steveadams)
11. 07:12 AM - Re: ELSA (Scott Thatcher)
12. 07:17 AM - new statement from CH? (David Downey)
13. 07:18 AM - Re: Re: Accident (Ken Lilja)
14. 07:44 AM - Re: Re: Accident (Jaybannist@cs.com)
15. 08:04 AM - Re: new statement from CH? (MHerder)
16. 08:16 AM - Re: Sign-on for structural analysis (Joshua)
17. 08:25 AM - Re: new statement from CH? (Gig Giacona)
18. 08:26 AM - Re: Accident (n85ae)
19. 08:26 AM - Re: Accident (Gig Giacona)
20. 09:01 AM - Re: Accident (steveadams)
21. 09:03 AM - Re: Re: Accident (Dave Austin)
22. 09:17 AM - Re: Accident (thesumak@aol.com)
23. 09:33 AM - 701: Elevator Bellcrank Neutral? (Tracy)
24. 09:43 AM - Re: Re: Accident (Dennis Shoup)
25. 09:52 AM - Re: Accident (Gig Giacona)
26. 10:21 AM - Re: Slanted Spar and "mini spar" ()
27. 10:47 AM - Re: Accident (Sabrina)
28. 11:01 AM - Recommended Wire Stripping Tool (Dave VanLanen)
29. 11:13 AM - Re: N701ZZ 1st flight (Jab 3300 w/retractable slats) (Stanley Challgren)
30. 11:39 AM - Re: Recommended Wire Stripping Tool (Jaybannist@cs.com)
31. 11:41 AM - Re: Recommended Wire Stripping Tool (Gig Giacona)
32. 11:53 AM - Re: Re: Accident (LarryMcFarland)
33. 11:57 AM - Re: Re: Accident (David Downey)
34. 12:07 PM - Re: Recommended Wire Stripping Tool (John Davis)
35. 12:19 PM - Re: Recommended Wire Stripping Tool (Craig Payne)
36. 12:23 PM - CH801 Door Frame Question (n85ae)
37. 12:24 PM - Re: new statement from CH? (Tim Juhl)
38. 12:54 PM - Re: Slanted Spar and "mini spar" (haven)
39. 01:14 PM - Re: Re: new statement from CH? (David Downey)
40. 01:35 PM - Re: Recommended Wire Stripping Tool (n85ae)
41. 01:36 PM - Re: CH801 Door Frame Question (n85ae)
42. 01:44 PM - Re: Re: new statement from CH? (Keith Ashcraft)
43. 01:52 PM - Re: CH801 Door Frame Question (n801bh@netzero.com)
44. 02:01 PM - Re: CH801 Door Frame Question (n85ae)
45. 02:05 PM - Re: Re: Recommended Wire Stripping Tool (Craig Payne)
46. 02:44 PM - Re: Recommended Wire Stripping Tool (n85ae)
47. 03:57 PM - Re: Accident (thesumak@aol.com)
48. 05:13 PM - Re: Accident (steveadams)
49. 05:18 PM - Re: Sign-on for structural analysis (steveadams)
50. 05:20 PM - Re: Re: new statement from CH? (David Downey)
51. 06:20 PM - 777 Wing Load Test (Jaybannist@cs.com)
52. 08:34 PM - Re: Recommended Wire Stripping Tool (Ron Lendon)
53. 08:34 PM - Re: 701: Elevator Bellcrank Neutral? (Stanley Challgren)
54. 09:05 PM - Re: Ye Olde Continental (Tommy Walker)
55. 09:54 PM - Re: Re: Accident (Ken Lilja)
56. 10:48 PM - Re: Re: Accident (Ken Lilja)
57. 11:02 PM - Re: Re: Accident (Ken Lilja)
Message 1
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The CH 640 also has a manual trim system which works very well which consists of
a wheel similar to a Cessna with a built in trim indicator. I don't know what
it costs to purchase seperately.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169767#169767
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Hey, when it comes to something like this, do the armchair designers really want
the truth, or would they rather cling to their preconceived notions? It doesn't
matter that the wings showed almost no torsion at all and no failure at the
ultimate load in testing or that the latest accident was not a structural failure.
The notion that there is a problem has taken a life of its own regardless
of fact or reason.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169768#169768
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Jay, you could be exactly right - look at the DC-10. Great airplane but many, many
people would not fly in one due to the string of (cause unrelated) catastrophic
crashes.
Jaybannist@cs.com wrote: This is not humble; but it is my opinion:
It is just not conscionable to condemn an airplane design based purely on hearsay;
which is exactly what is happening on this forum. There is absolutely no
proof that any of the XL crashes were because of a design flaw or structural
deficiency. None. To assert otherwise is quite simply not rational. It is purely
emotional speculation. Emotional speculation may be a fun game for some of
you, but it is not productive. In fact, it is downright destructive.
The structure of this airplane has been analyzed and load tested twice. The second
time, it was monitored by an independent engineer. Do you really believe
that a professional engineer would support a faulty analysis or load test?
Larry McFarland and Rick Lindstrom have told us that Zenith is addressing this
issue yet another time. Their response is expected before the end of next week.
I believe that a rational thinking person would be willing to wait for that
response instead of immediately pursuing an emotion-based and ill-founded wild
goose chase.
If you don't have confidence in this airplane, Zenith or Chris Heintz, I strongly
suggest you do us all a favor: minimize your losses - stop building, or finish
it and sell it. And get off this abominable witch hunt!
Jay in Dallas CH 601XL N2630J "Lil Bruiser"
Dave Downey
Harleysville (SE) PA
100 HP Corvair
---------------------------------
Never miss a thing. Make Yahoo your homepage.
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Could a 701 style Flap actuator be adapted?
The wheel type is what I was thinking of, when I posted the question. Is there
a vertical slot cut in the leading edge of the elevator for the the cable?
I like the areo conversions idea quit a lot and though the 701 elevator is huge,
does this limit the amount of movement available to maneuver the airplane?
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=169771#169771
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On Fri, Mar 14, 2008 at 02:32:47AM -0700, steveadams wrote:
> Hey, when it comes to something like this, do the armchair designers
> really want the truth, or would they rather cling to their preconceived
> notions? It doesn't matter that the wings showed almost no torsion at all
> and no failure at the ultimate load in testing or that the latest accident
> was not a structural failure. The notion that there is a problem has taken
> a life of its own regardless of fact or reason.
I can't speak for the others who are being taken to task here by several
posters, but as for me, i just want to know the plain, unvarnished truth.
I'll accept that the Australian accident was likely not due to structural
failure. The British one was, at least in part. What about the one in Spain?
(FWIW, I've been to Madrid twice on business, and like the place.) What
about the AMD aircraft in California? (See the list archives for 11 November
2006 for the NTSB preliminary report...though I do wonder why they haven't
issued a final report 16 months later.) That one would be very hard to blame
on construction issues.
The real world trumps theory every time. If it's a problem with the
aircraft's structural design, especially one that would not be revealed by
static testing, then I want to know so I can keep tabs on a fix. If it's a
problem with how the plane is flown, I want to know so I can avoid doing
that. If it's some other kind of problem, I want to know so I can see that
it doesn't affect me or my aircraft.
I don't think it's a common problem, or one that is easy to encounter, or
else there would be more than the 35 accidents in the NTSB database (across
all models of the CH601). I'm not nervous about getting mine and going
flying. Even so, I want to know the truth. That's all.
--
Jay Maynard, K5ZC http://www.conmicro.com
http://jmaynard.livejournal.com http://www.tronguy.net
Fairmont, MN (FRM) (Yes, that's me!)
AMD Zodiac CH601XLi N55ZC (getting ready to order)
Message 7
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I am not taking anyone to task for being concerned and wanting more information.
What I have a problem with are a few posters who already have in their minds
decided that; 1. there is a definite structural problem, 2. that they know where
in the wing the structural problem exists, and 3. have designed fixes for
this imaginary problem without any basis in fact, scientific evidence, or even
real theoretical analysis to back any of it up. I could say that the failures
were due to the builders using blue scotchbrite pads and have as much factual
and scientific basis as anything anyone else has proposed. I don't even have
a dog in this fight, I have no plans to ever fly a 601. You have to have trust
in your aircrafts design. If not you need to either do everything necessary in
your mind to achieve that level of trust based on facts and science, or find
a design you can trust.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169779#169779
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| Subject: | Re: Sign-on for structural analysis |
Depending on Cost, I'm In
--------
John
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169780#169780
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| Subject: | 701: Elevator Bellcrank Neutral? |
Hi Guys
I'm installing the pitch control bellcrank 7-C-1-1 to the pitch
control rod 7-C-1-3 and I can't seem to find a reference to the
neutral position of the bellcrank. Is it meant to be perpendicular to
the cabin floor? The rod will end up being a lot shorter than the
685mm in the drawings. Jari, you had the same question back last
summer...
And for that matter, the control stick is meant to be neutral
according to taste. Without the seat cushions in I can't really get a
feel for that. Where did you guys start from?
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| Subject: | Re: Armchair Engineer |
Maybe I'm wrong, but it looks to me like he's proposing a method to provide the
required torsional stability in a wing that is lighter than traditional methods
used to provide this stability. It says nothing of "fixing a problem with torsional
stability".
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169782#169782
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Hi Jay,
I managed to get the E-LSA registration under the loophole that existed
up until Jan 31, 2008 for registration of Fat Ultralights as well as any
aircraft that fit the LSA standards. The fact that I also was using a
Corvair engine was not a consideration as long as the factory allows the
use of one as well, and in fact, they even suggest that the aircraft be
built using the Corvair as one of the optional engine choices. For that
reason I was given the 5 hour flyoff. That option has now passed
however... UNLESS you were able to get the aircraft registered as an
ELSA prior to Jan 31, 2008. THEN you would have another two years
(through an extension that was given the day following the expiration
date) to obtain your sign off.
So, unless you already have the aircraft registered as ELSA (N Number),
you're out of luck trying to get anything done unless you DO have an
identical aircraft to the factory built version.
Hope that answers the question.
<<Not to pick on you personally, Scott; your signature got me to
wondering...
I thought an E-LSA needed to be identical to a factory-built SLSA aside
from
the builder. Is this not so? If it is so, how does one register a Zodiac
XL
with anything but an O-200 as an E-LSA?>>
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| Subject: | new statement from CH? |
gentlemen; there is drastic difference between the +/-6G stated on the front page
one of my plans (still current release page btw) and +6/-3 as stated in the
clipping attributed to CH!
Dave Downey
Harleysville (SE) PA
100 HP Corvair
---------------------------------
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I am giving thought to installing diagonal ribs between the stock ones.
I seem to remember that diagonal ribs are good in torsion. The Ercoupe
uses this design. Be careful or random strengthening as this could
shift loads to other areas and cause more problems.
What I would like to know is if they had wing lockers, what type of
aileron hinge and how much attention was given to aileron rigging
especially cable tension.
Ken Lilja
ashontz wrote:
>
> I agree. The wings are plenty strong in static load. Dynamically, I'm not so
sure. Extra ribs provide extra torsional stability and strength, as well as actually
making the wings stronger in a pure positive or negative load. Shorter
segments to transmit the same load across equals less leverage to crumple the
skins, particularly in compression. Think of a 5' fishing pole with only one eye
at the very end of the pole. Now think of the same pole with an eye every 6
inches. Much stronger under load.
>
> I would guess that if you could stand next to that inverted Zenith wing when
it was being static tested, and just touched it, it would hobble and bobble all
over the place, possibly even notice a bit of a "slow motion flutter".
>
>
>
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Ken,
Exactly what known problem are you thinking about solving?
Jay in Dallas
Ken Lilja <planes_by_ken@bellsouth.net> wrote:
>
>I am giving thought to installing diagonal ribs between the stock ones.
>I seem to remember that diagonal ribs are good in torsion. The Ercoupe
>uses this design. Be careful or random strengthening as this could
>shift loads to other areas and cause more problems.
>What I would like to know is if they had wing lockers, what type of
>aileron hinge and how much attention was given to aileron rigging
>especially cable tension.
>Ken Lilja
>
>ashontz wrote:
>>
>> I agree. The wings are plenty strong in static load. Dynamically, I'm not so
sure. Extra ribs provide extra torsional stability and strength, as well as actually
making the wings stronger in a pure positive or negative load. Shorter
segments to transmit the same load across equals less leverage to crumple the
skins, particularly in compression. Think of a 5' fishing pole with only one
eye at the very end of the pole. Now think of the same pole with an eye every
6 inches. Much stronger under load.
>>
>> I would guess that if you could stand next to that inverted Zenith wing when
it was being static tested, and just touched it, it would hobble and bobble all
over the place, possibly even notice a bit of a "slow motion flutter".
>>
>>
>>
>
>
Message 15
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| Subject: | Re: new statement from CH? |
Taken directly from the AMD website: www.newplane.com
AMD ZODIAC
PERFORMANCE
(AT GROSS)
CONTINENTAL 0-200 (100 HP) SPECIFICATIONS (STANDARD)
CONTINENTAL 0-200 (100 HP)
CRUISE SPEED (TAS)
130 MPH
CABIN WIDTH
44 INCHES
STALL NO FLAPS (LSA)
51 MPH
EMPTY WEIGHT
770 LBS
STALL WITH FLAPS
44 MPH
GROSS WEIGHT
1320 LBS
RATE OF CLIMB
1,000 FPM
USEFUL LOAD
550 LBS
FUEL CAPACITY
30 GAL
DESIGN LOAD (ULT)
ENDURANCE 5.5 HRS
SERVICE CEILING 12,000 FT
RANGE (MILES)
715 MILES
WING AREA
132 SQ. FT
This is a good question, I have wondered the same thing on several occasions.
My drawings issued in September of 07 also state Plus or Minus 6G. Obviously
this is a large discrepancy. What loads were the airframe brought up to in the
tests? Did they only test to +6G -3G in June or did they go +-6?
--------
One Rivet at a Time!
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169805#169805
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| Subject: | Re: Sign-on for structural analysis |
Hi there guys,
I'm a nobody building a 701 but....
I'm really sorry to see you guys saying such mean things to each other.
I read all of your posts, twice, everyday.
You guys are like my pretend family!
My fantasy Brothers from another mother!
You are all the grandfathers I never had!
(I'm not sayin your old I just like to imagine my mentors old and wise with long
beards sitting at a ZAC emblazoned round table in very large throne like engineering
armchairs. Dont worry, Your all wearing clothes in my imagination!)
Stop fighting. Your crushing my preconceived notion that you are actually all super
human. Makes me not want to ask any stupid questions about my build for fear
of being flamed at which could easily lead to me making a stupid mistake.
All kidding aside,
Why dont you guys give your money to Zenith? All of this speculation
& conjecture may force Zenith to do more load testing at there own great expense.
They will do so just to set YOUR minds at ease. Surely you can trust Zenith
to hire an independant pary? They may have to anyway. It looks like Zenith
sacrificed at least two airframes in their tests. I dont know but i dont think
your 3000 or so bucks is going to go very far. But it would help to offset
their costs should they feel forced into doing another load test. It would also
serve to reinforce your good intentions with the rest of this little community.
To be honest I would be a little let down if after all this talk and Zenith
feels pressured to do another test, would you just accept the findings and let
Zenith incure the cost?
So what do you guys all do when you go down to the barbecue and meet each other
anyways? Wear fake name tags or just fist fight? Sheesh.
Im kidding. Please dont yell at me. Im nobody. I just wish you guys would get back
to the business of building so I can learn something.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169806#169806
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| Subject: | Re: new statement from CH? |
I just e-mailed this question to Zenith. So let's see what they have to say. I'll
post their reply.
--------
W.R. "Gig" Giacona
601XL Under Construction
See my progress at www.peoamerica.net/N601WR
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169808#169808
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If I had load tested that wing, in the photo's. The last photo in the series
would have been the broken wing. That's what is missing in my opinion.
A lot can be learned from testing to complete failure.
Jeff.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169809#169809
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How do you propose to test this new design? Are you going to stress it as the Zenith
design as been stressed?
planes_by_ken(at)bellsout wrote:
> I am giving thought to installing diagonal ribs between the stock ones.
> I seem to remember that diagonal ribs are good in torsion. The Ercoupe
> uses this design. Be careful or random strengthening as this could
> shift loads to other areas and cause more problems.
> What I would like to know is if they had wing lockers, what type of
> aileron hinge and how much attention was given to aileron rigging
> especially cable tension.
> Ken Lilja
>
--------
W.R. "Gig" Giacona
601XL Under Construction
See my progress at www.peoamerica.net/N601WR
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169810#169810
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Do any of the armchair designers have an understanding of doing static testing
on a wing? When you see those pictures of wings piled high with sandbags, do you
ask yourself just how they decided to place the weight were they did? I'm no
engineer, but I can read. Perhaps this might educate some as much as it did
me. A friend who is an engineer sent me the following. I'm sorry I don't have
the referenced figures......
_________________________________________________________
The total load that the wing must support is:
the weight of the aircraft
multiplied by the load factor (in this case, the 3.8Gs necessary to qualify the
airplane for the "Standard" category)
plus or minus the tail load for a particular flight condition (the center of gravity
location was varied from most forward to most aft to determine the tail
load to add [or subtract] from the wing load.)
Thats the total load. Now, how the load is distributed across the wing varies with
the flight condition. Speed, angle of attack and control surface deflection
all contribute to variations in distribution. It might be possible to put an
unacceptable strain on one point of the wing without exceeding the total load.
Loads are not constant from root to tip, nor from leading edge to trailing edge.
From all the flight loads considered, we select three "worst case" load conditions
to test. If the wing is strong enough to survive these loads, then it
will be strong enough in all the other flight conditions.
The first test case:
This is the result of a 3.8G symmetrical pull-up at 10 percent over redline airspeed.
The wing angle of attack (AOA) for this case is 5 degrees. When the worst
case tail download is considered, this puts the largest total load on the wing/center
section and imposes the "worst-case" total bending load that the wing
must carry. We design the wings to meet the standards of FAR Part 23 where
this case is labeled "Condition D" so we have adopted the same terminology. You
can get an idea of the spanwise load distribution for this case in Curve 1 of
Fig. 2.
Chordwise distribution is shown on Fig. 4. Notice that the majority of the load
on the forward one third of the chord.
The second test case that we selected corresponds to Condition A, (again, an FAA
label we have adopted) the upper left corner of the envelope shown in Fig 1.
This would result from a 3.8G symmetrical pull-up at maneuvering speed. While
this is not the worst-case total load, it occurs at a 15 degree angle of attack.
The spanwise distribution is shown on the upper curve of Fig. 2, but the interesting
stuff happens elsewhere. At this AOA, the load on the wing forces it
forward as well as lifting perpendicular to the chord plane. This results in
a tension load on the joint between the rear spar and the fuselage. The chordwise
load distribution for Condition A is shown in Fig. 3, where we can see that
this condition results in most of the load being applied very near the front
of the wing, which tries to twist the leading edge up. In engineerspeak it "places
a large leading-edge-up torsional load on the wing." The wing is subjected
to bending in two planes (forward and up) and twisting at the same time.
The third test case we selected corresponds to a symmetrical pull-up at two thirds
of 3.8G at maneuvering speed plus full trailing-edge-down aileron deflection.
You cant read this case directly off the V-n diagram, but it is a good example
of how combinations of loads must be considered. The wing angle of attack
for this case is 10 degrees. The load for this condition is centered quite forward
on the chord of the non-aileron portion of the wing (Fig. 3). The additional
lift due to aileron deflection on the outboard portion of the wing (see the
lower curve on Fig. 2) places a large bending load on the outboard wing. Because
this lift is centered further aft (Fig. 5) it exerts a large trailing-edge-up
twist as well.
We obviously cant duplicate a dynamic situation in the shop, so we have to figure
out the load distribution and simulate it with simple weight. If you superimpose
the spanwise and chordwise load distributions on top of each other, you
end up with a reasonably accurate picture of the total distribution of load over
the entire wing root to tip and leading edge to trailing edge.
_________________________________________________________
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169818#169818
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Just a reminder.. it was the centre section of the spar that appeared to be
the weakest link in the UK crash..
Dave Austin 601HDS - 912, Spitfire Mk VIII
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In the May 10, 2007
letter, Chris Heintz warned us about the serious damage potential of rapid f
ull
forward stick movement at cruise speed.=C2-
This is due to the large amount of elevator control which was designed
in to have enough elevator authority to provide control for flights made wit
h improper
center of gravity computations.=C2- Given
what has happened over the last couple of years, it may be wise to re think
that design philosophy.=C2- It would seem reasonable
to limit elevator control to make rapid full stick movement at cruise a litt
le less
apt to rip the wings off and live with the compromised improper center of
gravity maneuverability.
=C2-
With regard to the recent posts that we should stop talking
about this, here=99s one vote that everyone has a right to express the
ir opinion
on this list. =C2-I don=99t think it=99s that
hard to separate the wheat from the chaff.
=C2-
Cheers,
Bill
Message 23
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| Subject: | 701: Elevator Bellcrank Neutral? |
hello
I have built a couple and I just made them perpendicular ,otherwise the bellcranck
get tight or hits the back of the seat and does not reach full deflection
and yes it would be a bit shorter
Tracy
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Message 25
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I was with you until you used the phrase "It would seem reasonable to limit elevator
control ...less apt to rip the wings off ..."
I don't know about you but I just might like to have that elevator control when
flying slow. I think a better answer would be to fly the aircraft in a manner
that doesn't over stress the design. I've been flying for over 30 years and I
have never felt the need to push full forward on the stick while at cruise speed.
There are lots of certified aircraft that have issues in certain flight parameters.
The answer is usually training or simply putting a sign in the cockpit or
the writing something in the POH. Or even in some cases regulation. Google Special
Federal Aviation Regulation No. 73.
And no one that I have seen has said anything about not talking about these issues.
The problem I and some of the others on the list is people who no not what
they hell they are talking about coming up with "Fixes" for a problem that might
or might not even be there.
In fact the only messages I've seen posted with the aim to limit a writer's "right
to express their opinion" have come from those who have posted fixes and were
later admonished for it being a bad idea.
I'm just glad it's Friday which means I'm going to have 2 days in a row to go work
on my "death trap to be" with weather that is supposed to be sunny and in
the mid 70's. Eat your heart out Northerners.
[quote="thesumak(at)aol.com"]In the May 10, 2007 letter, Chris Heintz warned us
about the serious damage potential of rapid full forward stick movement at cruise
speed. This is due to the large amount of elevator control which was designed
in to have enough elevator authority to provide control for flights made
with improper center of gravity computations. Given what has happened over the
last couple of years, it may be wise to re think that design philosophy. It
would seem reasonable to limit elevator control to make rapid full stick movement
at cruise a little less apt to rip the wings off and live with the compromised
improper center of gravity maneuverability.
With regard to the recent posts that we should stop talking about this, heres
one vote that everyone has a right to express their opinion on this list.
I dont think its that hard to separate the wheat from the chaff.
Cheers,
Bill
Supercharge your AIM. Get the AIM toolbar (http://download.aim.com/client/aimtoolbar?NCID=aolcmp00300000002586) for your browser.
> [b]
--------
W.R. "Gig" Giacona
601XL Under Construction
See my progress at www.peoamerica.net/N601WR
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169832#169832
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| Subject: | Re: Slanted Spar and "mini spar" |
It can be done easier than that-- Cessna uses a "mini-longeron" rivete
d lengthwise to the upper skin. Either looke at a parts manual or stop
in at a wing shop. It's simple, light, and effective. Only takes a no
tch in the top of the rib to accommodate it.=0A=0APaul Rodriguez
=0A ----- Original Message ----- =0A From: Doug Sire<mailto:ds
ire@imt.net> =0A To: Zenith-List@matronics.com<mailto:Zenith-List@
matronics.com> =0A Sent: Thursday, March 13, 2008 5:21 PM=0A S
ubject: Zenith-List: Slanted Spar and "mini spar"=0A=0A=0A I
too have felt a bit uneasy about the slanted spar. It does almost s
eem like some type of triangular box spar would be better.=0A=0A
=0A=0A One approach to strengthen the spar when encountering
loads from the front and below would be to cut a slot in each rib bet
ween the front lightening hole and the spar perpendicular to the spar,
and then insert a "mini-spar" through all of the ribs. It would be
attached to each rib with a triangular formed bracket. That would ac
complish some of what the Air Force patent article (1979) was trying t
o accomplish. It would certainly act to resist any bending back of t
he main spar.=0A=0A =0A=0A I'm no engineer, although I
did stay at a Holiday Inn Express once, and I broke plenty of things o
n the farm as a kid, so I have some sense of how things fail structura
lly. I have the complete kit but will just be starting soon on the H
S.=0A=0A =0A=0A =0A=0A Doug Sire=0A=0A 6
=======================
=======================
atronics.com/Navigator?Zenith-List<http://www.matronics.com/Navigator?
=======================
======================0A_
=======================
=======================
http://www.matronics.com/contribution<http://www.matronics.com/contri
=======================
====================0A=0A
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If you look at my interior, I have the sticks coming up through a stop quadrant.
Even though I have external control surface stops, I also have these internal
stops that stop before full deflection but can be flexed to full deflection.
So too, I used kangaroo boots. For extreme forward or rearward movement,
the skins must stretch one side and crunch up on the other side. This causes
increasing resistance as you push full forward or full back, etc. There is
little resistance in 50% of movement, increasing for the next 25% and increasing
further the last 25%. The first time I flew a Cirrus I had to use two hands
for large movement--their controls must incorporate some sort of resistance
to large movement.
So too, my baggage compartment is about 60% of the factory compartment, one reason
was to place a battery and vents back there, but more so to prevent accidental
stick movement when reaching too far back, a concern of CHs. I can easily
reach the back wall of the compartment without moving anything below my waist.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169842#169842
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| Subject: | Recommended Wire Stripping Tool |
I have been reading my new copy of the AeroElectric Connection manual, as
well as the website information, and I have not found any specific
recommendation for the best wire stripping tool. My understanding is that
the most important aspect of a good tool is that it does not nick the
underlying wire strands when stripping insulation. Can the list recommend a
good tool from personal experience?
Thanks,
Dave Van Lanen
Madison, WI
601XL - Elevator (preparing to wire RA elevator trim servo)
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| Subject: | Re: N701ZZ 1st flight (Jab 3300 w/retractable slats) |
On Jan 18, 2008, at 6:43 PM, James Sagerser wrote:
> Jim:
I am wondering how the 3300 is working out on your 701. If there are
no particular cooling problems that are not solvable I am planning on
taking advantage of the 3300 sale price that is available until April
15th.
Having spent about 160 hours flying our 601 HDS/Jab 3300 before
getting the cooling problems under control, I can well understand that
some problems might still persist. If their are still problems I like
the engine so much that the only question for me is: Are they solvable?
Appreciate your response.
Stan
N701VG
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| Subject: | Recommended Wire Stripping Tool |
Dave,
For AWG16 and larger, I use a stripper from Radio Shack; the kind that grips the
wire; has calibrated, sharpened slots at the start of the strip, and pivots
to complete the strip.
For anything smaller I use a technique acquired in an Army electronics school.
With a diagonal cutter ("dikes") carefully score around the start of the strip.
Then, with your hand around the dikes at the pivot point, apply gentle pressure
at the strip point and pull. It takes a little practice, but it is easy
to get the hang of. Effective, quick and easy.
Jay in Dallas CH 601XL N2630J "Lil Bruiser"
"Dave VanLanen" <davevanlanen@sbcglobal.net> wrote:
>I have been reading my new copy of the AeroElectric Connection manual, as
>well as the website information, and I have not found any specific
>recommendation for the best wire stripping tool. My understanding is that
>the most important aspect of a good tool is that it does not nick the
>underlying wire strands when stripping insulation. Can the list recommend a
>good tool from personal experience?
>
>Thanks,
>Dave Van Lanen
>Madison, WI
>601XL - Elevator (preparing to wire RA elevator trim servo)
>
Message 31
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| Subject: | Re: Recommended Wire Stripping Tool |
I got the most expensive one Radio Shack had on the shelf and it has worked pretty
well for me.
http://www.radioshack.com/product/index.jsp?productId 62787&cp 32058.2032237.2032319&parentPage=family
I don't use the crimper that is on it.
--------
W.R. "Gig" Giacona
601XL Under Construction
See my progress at www.peoamerica.net/N601WR
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169846#169846
Message 32
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Ken,
I have to add something here. The idea that you should redesign the
wings, ribs or anything else is wrong.
There is no proven fault in the design and the accidents are more likely
the cause of poor assembly,
construction errors or flying error. If you redesign the rib structure,
you become responsible and
you can increase the problem you sought to resolve. Structures have
long and short coupled deflections
that permit progressive flexing from the outer panels to the inner. If
you make the wing too rigid, you bring
force and stresses to the fuselage and structure more quickly that can
exceed the design. I'd recommend
you build and respect the plans before considering those changes and
talk with the designer or Nick
before doing so.
My recommendation would be to keep faith with the plans. My hunch is
that something outside of the
design will be found that links common problem variations to something
outside the scope of the plans.
If you want to fund a "finite element design review", send the money to
Zenith to support the most important
source of information you have. I'm sure this kind of response would be
appreciated and say we're all in this together.
Larry McFarland 601HDS at www.macsmachine.com
Jaybannist@cs.com wrote:
>
> Ken,
>
> Exactly what known problem are you thinking about solving?
>
> Jay in Dallas
>
> Ken Lilja <planes_by_ken@bellsouth.net> wrote:
>
> I am giving thought to installing diagonal ribs between the stock ones.
> I seem to remember that diagonal ribs are good in torsion. The Ercoupe
> uses this design.
>
Ken Lilja
>
>>
>
>
>
Message 33
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I have to ask: does the Cirrus use anti servo tabs? The Thorp T-18 that I used
to fly did and the control resistance was progressive.
If you look at my interior, I have the sticks coming up through a stop quadrant.
Even though I have external control surface stops, I also have these internal
stops that stop before full deflection but can be flexed to full deflection.
So too, I used kangaroo boots. For extreme forward or rearward movement,
the skins must stretch one side and crunch up on the other side. This causes
increasing resistance as you push full forward or full back, etc. There is
little resistance in 50% of movement, increasing for the next 25% and increasing
further the last 25%. The first time I flew a Cirrus I had to use two hands
for large movement--their controls must incorporate some sort of resistance
to large movement.
So too, my baggage compartment is about 60% of the factory compartment, one reason
was to place a battery and vents back there, but more so to prevent accidental
stick movement when reaching too far back, a concern of CHs. I can easily
reach the back wall of the compartment without moving anything below my waist.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169842#169842
Dave Downey
Harleysville (SE) PA
100 HP Corvair
---------------------------------
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| Subject: | Re: Recommended Wire Stripping Tool |
Hi Dave,
I've got the Stripmaster from stein air at
http://www.steinair.com/tools.htm. Its a bit pricey but does a nice job
and certainly doesn't nick the wire.
John
Dave VanLanen wrote:
>
> I have been reading my new copy of the AeroElectric Connection manual,
> as well as the website information, and I have not found any specific
> recommendation for the best wire stripping tool. My understanding is
> that the most important aspect of a good tool is that it does not nick
> the underlying wire strands when stripping insulation. Can the list
> recommend a good tool from personal experience?
>
> Thanks,
>
> Dave Van Lanen
>
> Madison, WI
>
> 601XL -- Elevator (preparing to wire RA elevator trim servo)
>
> *
>
>
> *
Message 35
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| Subject: | Recommended Wire Stripping Tool |
If you search the Matronics aeroelectric list archives you should find some
leads. There are automatic strippers and then there are automatic strippers.
The ones like Radio Shack sells are automatic but they still have sharp
cutting blades which can nick the wires. The better (and more expensive)
ones basically put a dent in the insulation and then pull it apart. The part
that puts the dent in the insulation is not a sharp edge. With practice you
can do the same operation with a cheap pair of the strippers that are two
flat bars joined with a bolt and with a V notch in both bars. Just get a
grip on the insulation with the V's, push away and increase your squeeze
until the insulation parts. The metal will never touch the conductor. But it
takes practice to develop a feel.
Back in Dec 2005 I bought one of the expensive automatic strippers from a
guy named Gary Edwards (gary21sn@hotmail.com) on the aeroelectric list. I
doubt that he has any more but this is what he wrote at the time:
"More info on the wire strippers from my e-mail from last night.
IDEAL Stripmaster - Model 45-1610-1
Has 16 to 26 gauge aircraft wire strip die
Made in the USA
This tool is the best wire stripper I have ever used. It is truly a "one
squeeze" automatic wire stripper. With one squeeze, it grips the wire at
the insulation, cleanly pulls the insulation off the wire. Release the
spring loaded handle and the tool releases its grip on the wire. No cut
wire strands.
The stripping die has separate sized stripping holes for 16, 18, 20, 22, 24,
26 gauge aircraft wire (die part number: 88A081X). So, no tool adjustments
are necessary for different size wire. It is ready to work right out of the
box.
This wire stripper is the "bench mark" that all others are measured by.
This is the one that Bob Knuckolls wrote about and has pictures of in his
article in the AeroElectric Connection.
If you are searching around for Ideal Stripmaster wire strippers, make sure
you search for the model 45-1610 as it is the specific one for aircraft
wire."
-- Craig
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of Dave VanLanen
Sent: Friday, March 14, 2008 11:57 AM
Subject: Zenith-List: Recommended Wire Stripping Tool
I have been reading my new copy of the AeroElectric Connection manual, as
well as the website information, and I have not found any specific
recommendation for the best wire stripping tool. My understanding is that
the most important aspect of a good tool is that it does not nick the
underlying wire strands when stripping insulation. Can the list recommend a
good tool from personal experience?
Thanks,
Dave Van Lanen
Madison, WI
601XL - Elevator (preparing to wire RA elevator trim servo)
Message 36
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| Subject: | CH801 Door Frame Question |
CH801 Question
For the life of me I cannot figure out how the 8F5-11 trim pieces get
installed it is page 7 of the following doc, but the picture is not clear
enough.
http://www.zenithair.com/stolch801/data/new/801fuselage-cabin-section9.pdf
Thanks!
Jeff
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169861#169861
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| Subject: | Re: new statement from CH? |
My plans list ultimate loads of +/- 6 g. I would hope that if the limits have
been changed that Zenith would share that info with builder / operators to avoid
any confusion.
General Info on loading: Limiting loads and ultimate loads
To receive type approval certification the design of a general aviation or ultralight
aircraft must conform with certain standards, among which are the in-flight
manoeuvring loads plus the turbulence induced loads which the structure must
be able to sustain. The turbulence loads are called the gust induced loads.
FAR part 23 is the recognised world standard for light aircraft certification
and the following is an extract: "... limit loads are the maximum loads to be
expected in service [i.e. the highest load expected in normal operations] and
ultimate loads are limit loads multiplied by a safety factor [of 1.5]. The structure
must be able to support limit loads without detrimental, permanent deformation.
At any load up to limit loads, the deformation may not interfere with
safe operation. The structure must be able to support ultimate loads without
failure for at least three seconds ..."
The minimum positive limit load factor which an aircraft in the 'normal' operational
category (at maximum take-off weight) must be designed to withstand is 3.8g.
For a non-aerobatic aircraft the negative limit load factor is 0.4 times
the positive limit which makes it 1.5g for the normal category. The ultimate
loads for the normal category are +5.7g and -2.25g. Amateur builders should aim
to meet the same minimum values for limiting load and ultimate load factors.
[At +6/ -3 the XL exceeds this requirement]
For aircraft with aerobatic capability the negative limit load factor must be 0.5
times the positive value. The 'utility' category (which includes training aircraft
with spin certification) limit loads are +4.4g and -2.2g while the 'acrobatic'
category limit loads are +6.0g and -3.0g.
Tim
--------
______________
CFII
Champ L16A flying
Zodiac XL - Jabiru 3300A
Working on fuselage
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169862#169862
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| Subject: | Re: Slanted Spar and "mini spar" |
Isn't that the same thing Vans does on the RV's?
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169863#169863
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| Subject: | Re: new statement from CH? |
please note that the 3 seconds without failure at ultimate is exactly that - if
the structure fails at 3.01 seconds under steady state ultimate load it passed.
There is no requirement for repeated capability. The rate of load application
and incrementation is also generally used to make the test as benign as possible
where transient loads resulting from turbulence or pilot error are generally
pulse loads...
My plans list ultimate loads of +/- 6 g. I would hope that if the limits have
been changed that Zenith would share that info with builder / operators to avoid
any confusion.
General Info on loading: Limiting loads and ultimate loads
To receive type approval certification the design of a general aviation or ultralight
aircraft must conform with certain standards, among which are the in-flight
manoeuvring loads plus the turbulence induced loads which the structure must
be able to sustain. The turbulence loads are called the gust induced loads.
FAR part 23 is the recognised world standard for light aircraft certification
and the following is an extract: "... limit loads are the maximum loads to be
expected in service [i.e. the highest load expected in normal operations] and
ultimate loads are limit loads multiplied by a safety factor [of 1.5]. The structure
must be able to support limit loads without detrimental, permanent deformation.
At any load up to limit loads, the deformation may not interfere with
safe operation. The structure must be able to support ultimate loads without
failure for at least three seconds ..."
The minimum positive limit load factor which an aircraft in the 'normal' operational
category (at maximum take-off weight) must be designed to withstand is 3.8g.
For a non-aerobatic aircraft the negative limit load factor is 0.4 times
the positive limit which makes it 1.5g for the normal category. The ultimate
loads for the normal category are +5.7g and -2.25g. Amateur builders should aim
to meet the same minimum values for limiting load and ultimate load factors.
[At +6/ -3 the XL exceeds this requirement]
For aircraft with aerobatic capability the negative limit load factor must be 0.5
times the positive value. The 'utility' category (which includes training aircraft
with spin certification) limit loads are +4.4g and -2.2g while the 'acrobatic'
category limit loads are +6.0g and -3.0g.
Tim
--------
______________
CFII
Champ L16A flying
Zodiac XL - Jabiru 3300A
Working on fuselage
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169862#169862
Dave Downey
Harleysville (SE) PA
100 HP Corvair
---------------------------------
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| Subject: | Re: Recommended Wire Stripping Tool |
The best thing is thermal strippers. You can find them by doing a google
search for "thermal stripper"
They will not nick the wires at all. They will cost a bit, but if you're really
picky they are the best way to go.
Jeff
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169867#169867
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| Subject: | Re: CH801 Door Frame Question |
Another note, I have not yet installed the fuel line trim so that may clear it
up for me. If anybody has some pics that would be great help.
Jeff
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169868#169868
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| Subject: | Re: new statement from CH? |
Just my $0.02 worth. Here is a video of Boeing doing a "static" load test t
o their 777 series wing. It seems in this test that there is no account for
turbulence, it is just a pure wing deflection until failure test.
http://www.youtube.com/watch?v=pe9PVaFGl3o
Don't know if this helps or hurts, or has any bearing on this discussion, b
ut it is just a data point.
Back to building my 701.
Keith
N 38.9947
W 105.1305
Alt. 9,100'
***************************************************************************
********************
David Downey wrote:
please note that the 3 seconds without failure at ultimate is exactly that
- if the structure fails at 3.01 seconds under steady state ultimate load i
t passed. There is no requirement for repeated capability. The rate of load
application and incrementation is also generally used to make the test as
benign as possible where transient loads resulting from turbulence or pilot
error are generally pulse loads...
Tim Juhl <juhl@avci.net><mailto:juhl@avci.net> wrote:
My plans list ultimate loads of +/- 6 g. I would hope that if the limits ha
ve been changed that Zenith would share that info with builder / operators
to avoid any confusion.
General Info on loading: Limiting loads and ultimate loads
To receive type approval certification the design of a general aviation or
ultralight aircraft must conform with certain standards, among which are th
e in-flight manoeuvring loads plus the turbulence induced loads which the s
tructure must be able to sustain. The turbulence loads are called the gust
induced loads. FAR part 23 is the recognised world standard for light aircr
aft certification and the following is an extract: "... limit loads are the
maximum loads to be expected in service [i.e. the highest load expected in
normal operations] and ultimate loads are limit loads multiplied by a safe
ty factor [of 1.5]. The structure must be able to support limit loads witho
ut detrimental, permanent deformation. At any load up to limit loads, the d
eformation may not interfere with safe operation. The structure must be abl
e to support ultimate loads without failure for at least three seconds ..."
The minimum positive limit load factor which an aircraft in the 'normal' op
erational category (at maximum take-off weight) must be designed to withsta
nd is 3.8g. For a non-aerobatic aircraft the negative limit load factor is
0.4 times the positive limit which makes it 1.5g for the normal category. T
he ultimate loads for the normal category are +5.7g and -2.25g. Amateur bui
lders should aim to meet the same minimum values for limiting load and ulti
mate load factors. [At +6/ -3 the XL exceeds this requirement]
For aircraft with aerobatic capability the negative limit load factor must
be 0.5 times the positive value. The 'utility' category (which includes tra
ining aircraft with spin certification) limit loads are +4.4g and -2.2g whi
le the 'acrobatic' category limit loads are +6.0g and -3.0g.
Tim
--------
______________
CFII
Champ L16A flying
Zodiac XL - Jabiru 3300A
Working on fuselage
Read this topic online
--
*************************************
Keith Ashcraft
ITT Industries
Advanced Engineering & Sciences
5009 Centennial Blvd.
Colorado Springs, CO
80919
(719) 599-1787 -- work
(719) 332-4364 -- cell
keith.ashcraft@itt.com<mailto:keith.ashcraft@itt.com>
________________________________
This e-mail and any files transmitted with it may be proprietary and are in
tended solely for the use of the individual or entity to whom they are addr
essed. If you have received this e-mail in error please notify the sender.
Please note that any views or opinions presented in this e-mail are solely
those of the author and do not necessarily represent those of ITT Corporati
on. The recipient should check this e-mail and any attachments for the pres
ence of viruses. ITT accepts no liability for any damage caused by any viru
s transmitted by this e-mail.
Message 43
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| Subject: | Re: CH801 Door Frame Question |
Geez... Looking at those drawing brought back some wonderful memories...
.
If I remember correctly the 5-11 kinda slips into the rear of the heavy
channel. From the top of the angled longeron to the top of the cabin 5-1
1 turns that heavy u channel into a box structure.
do not archive
Ben Haas
N801BH
www.haaspowerair.com
-- "n85ae" <n85ae@yahoo.com> wrote:
CH801 Question
For the life of me I cannot figure out how the 8F5-11 trim pieces get
installed it is page 7 of the following doc, but the picture is not clea
r
enough.
http://www.zenithair.com/stolch801/data/new/801fuselage-cabin-section9.p
df
Thanks!
Jeff
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169861#169861
========================
===========
========================
===========
========================
===========
========================
===========
_____________________________________________________________
Improve your ability to get around with a wheel chair van. Click now!
http://thirdpartyoffers.netzero.net/TGL2221/fc/Ioyw6i4sxOvByrA8cpo9ZBxVE
e0yExG9tHc81gl8mf6L5p3wLhidXk/
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| Subject: | Re: CH801 Door Frame Question |
The kit's not bad, and the manuals overall are not totally horrible ... I
was just unlucky that my "clairvoyance" was backordered when I bought it.
Help!
Thanks,
Jeff
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169873#169873
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| Subject: | Re: Recommended Wire Stripping Tool |
Do the thermal strippers work with tefzel?
-- Craig
-----Original Message-----
From: owner-zenith-list-server@matronics.com
[mailto:owner-zenith-list-server@matronics.com] On Behalf Of n85ae
Sent: Friday, March 14, 2008 2:32 PM
Subject: Zenith-List: Re: Recommended Wire Stripping Tool
The best thing is thermal strippers. You can find them by doing a google
search for "thermal stripper"
They will not nick the wires at all. They will cost a bit, but if you're
really
picky they are the best way to go.
Jeff
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169867#169867
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| Subject: | Re: Recommended Wire Stripping Tool |
That's the only thing I have ever used them for to be honest. I think other
wire types might not work so well for thermal stripping. One thing is that
there is smoke produced when you do it, so an open door and a fan are a
good thing.
You adjust the temp first, then basically you just clamp on the wire where
you want to cut the insulation, rotate the tool. Release it. Then you grab
the insulation and tug it off. It does not even disturb the twist of the wires.
I used one exclusively for about three years at a job I had. They are
very nice tools. They are a bit expensive, though. I personally just use
a Klein conventional stripper for my airplane project. The key is clamp
it on rotate it, then pull the insulation off with your fingers. That will avoid
90+ percent of the nicks.
Regards,
Jeff
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169880#169880
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Thanks for your response Gig.=C2-=C2- From what Rick and Mark say, it ap
pears that
the Zenith folks do not share in your ambivalence concerning a possible prob
lem
with elevator authority in the XL.=C2-=C2- I
can=99t predict the future, but I would not be surprised if Zenith off
ers a mod
that is something along the lines of what Sabrina has already done on her ow
n.
=C2-
Cheers,
Bill
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Every airplane has a Va speed, usually significantly less than normal cruise speed.
Something like an anti-servo tab as is on the 640 may make some sense to
make it more difficult to force severe elevator deflections at higher speeds.
However, you could create new problems at lower speeds by simply limiting elevator
travel. Like any other plane, just fly within the envelope rather than trying
to change the envelope to match one parameter of how you want to fly.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169900#169900
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| Subject: | Re: Sign-on for structural analysis |
Has anyone thought to ask zenith or AMD for copies of their data from structural
analysis and load testing. Since it's an sLSA, I would think they should have
it all well documented and it might be a lot cheaper to hire someone to look
over their data and give you their thoughts rather than trying to re-invent the
wheel. They may not agree to share it, but it's worth a try.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169901#169901
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| Subject: | Re: new statement from CH? |
We do test like that - but no one here assumes that the static load is the big
driver in the certification of the plane. Most of our structures are fatigue limited.
Keith Ashcraft <keith.ashcraft@itt.com> wrote: Just my $0.02 worth. Here
is a video of Boeing doing a "static" load test to their 777 series wing. It seems
in this test that there is no account for turbulence, it is just a pure wing
deflection until failure test.
http://www.youtube.com/watch?v=pe9PVaFGl3o
Don't know if this helps or hurts, or has any bearing on this discussion, but
it is just a data point.
Back to building my 701.
Keith
N 38.9947
W 105.1305
Alt. 9,100'
***********************************************************************************************
David Downey wrote: please note that the 3 seconds without failure at ultimate
is exactly that - if the structure fails at 3.01 seconds under steady state ultimate
load it passed. There is no requirement for repeated capability. The
rate of load application and incrementation is also generally used to make the
test as benign as possible where transient loads resulting from turbulence or
pilot error are generally pulse loads...
My plans list ultimate loads of +/- 6 g. I would hope that if the limits have
been changed that Zenith would share that info with builder / operators to avoid
any confusion.
General Info on loading: Limiting loads and ultimate loads
To receive type approval certification the design of a general aviation or ultralight
aircraft must conform with certain standards, among which are the in-flight
manoeuvring loads plus the turbulence induced loads which the structure
must be able to sustain. The turbulence loads are called the gust induced loads.
FAR part 23 is the recognised world standard for light aircraft certification
and the following is an extract: "... limit loads are the maximum loads to
be expected in service [i.e. the highest load expected in normal operations]
and ultimate loads are limit loads multiplied by a safety factor [of 1.5]. The
structure must be able to support limit loads without detrimental, permanent
deformation. At any load up to limit loads, the deformation may not interfere
with safe operation. The structure must be able to support ultimate loads without
failure for at least three seconds ..."
The minimum positive limit load factor which an aircraft in the 'normal' operational
category (at maximum take-off weight) must be designed to withstand is
3.8g. For a non-aerobatic aircraft the negative limit load factor is 0.4 times
the positive limit which makes it 1.5g for the normal category. The ultimate
loads for the normal category are +5.7g and -2.25g. Amateur builders should aim
to meet the same minimum values for limiting load and ultimate load factors.
[At +6/ -3 the XL exceeds this requirement]
For aircraft with aerobatic capability the negative limit load factor must be
0.5 times the positive value. The 'utility' category (which includes training
aircraft with spin certification) limit loads are +4.4g and -2.2g while the 'acrobatic'
category limit loads are +6.0g and -3.0g.
Tim
--------
______________
CFII
Champ L16A flying
Zodiac XL - Jabiru 3300A
Working on fuselage
Read this topic online
ttp://www.matronics.com/Navigator?Zenith-List ics.com .matronics.com/contribution
--
************************************* *************************************
Keith Ashcraft
ITT Industries
Advanced Engineering & Sciences
5009 Centennial Blvd.
Colorado Springs, CO
80919
(719) 599-1787 -- work
(719) 332-4364 -- cell
keith.ashcraft@itt.com
---------------------------------
This e-mail and any files transmitted with it may be proprietary and are intended
solely for the use of the individual or entity to whom they are addressed.
If you have received this e-mail in error please notify the sender. Please note
that any views or opinions presented in this e-mail are solely those of the
author and do not necessarily represent those of ITT Corporation. The recipient
should check this e-mail and any attachments for the presence of viruses.
ITT accepts no liability for any damage caused by any virus transmitted by this
e-mail.
Dave Downey
Harleysville (SE) PA
100 HP Corvair
---------------------------------
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| Subject: | 777 Wing Load Test |
Keith,
If I had an airplane with wings that could withstand 153% of the design ULTIMATE
load, 100% being the WORST gust load expected, I would probably never pay attention
to maneuvering speed. I couldn't believe how much those wings deflected
before they failed! And I can't believe anyone would demand a more strenuous
positive load test than this one, "static" or not.
Jay in Dallas
Do not archive
>Keith Ashcraft <keith.ashcraft@itt.com> wrote: Just my $0.02 worth. Here
is a video of Boeing doing a "static" load test to their 777 series wing. It
seems in this test that there is no account for turbulence, it is just a pure
wing deflection until failure test.
>
> http://www.youtube.com/watch?v=pe9PVaFGl3o
>
> Don't know if this helps or hurts, or has any bearing on this discussion, but
it is just a data point.
>
>
> Back to building my 701.
>
> Keith
> N 38.9947
> W 105.1305
> Alt. 9,100'
> ***********************************************************************************************
>
>
> David Downey wrote: please note that the 3 seconds without failure at ultimate
is exactly that - if the structure fails at 3.01 seconds under steady state
ultimate load it passed. There is no requirement for repeated capability. The
rate of load application and incrementation is also generally used to make the
test as benign as possible where transient loads resulting from turbulence or
pilot error are generally pulse loads...
>
>
> My plans list ultimate loads of +/- 6 g. I would hope that if the limits have
been changed that Zenith would share that info with builder / operators to avoid
any confusion.
>
> General Info on loading: Limiting loads and ultimate loads
>
> To receive type approval certification the design of a general aviation or ultralight
aircraft must conform with certain standards, among which are the in-flight
manoeuvring loads plus the turbulence induced loads which the structure
must be able to sustain. The turbulence loads are called the gust induced loads.
FAR part 23 is the recognised world standard for light aircraft certification
and the following is an extract: "... limit loads are the maximum loads to
be expected in service [i.e. the highest load expected in normal operations]
and ultimate loads are limit loads multiplied by a safety factor [of 1.5]. The
structure must be able to support limit loads without detrimental, permanent
deformation. At any load up to limit loads, the deformation may not interfere
with safe operation. The structure must be able to support ultimate loads without
failure for at least three seconds ..."
>
> The minimum positive limit load factor which an aircraft in the 'normal' operational
category (at maximum take-off weight) must be designed to withstand is
3.8g. For a non-aerobatic aircraft the negative limit load factor is 0.4 times
the positive limit which makes it 1.5g for the normal category. The ultimate
loads for the normal category are +5.7g and -2.25g. Amateur builders should
aim to meet the same minimum values for limiting load and ultimate load factors.
[At +6/ -3 the XL exceeds this requirement]
>
> For aircraft with aerobatic capability the negative limit load factor must be
0.5 times the positive value. The 'utility' category (which includes training
aircraft with spin certification) limit loads are +4.4g and -2.2g while the 'acrobatic'
category limit loads are +6.0g and -3.0g.
>
> Tim
>
> --------
> ______________
> CFII
> Champ L16A flying
> Zodiac XL - Jabiru 3300A
> Working on fuselage
>
>
>
>
> Read this topic online
> ttp://www.matronics.com/Navigator?Zenith-List ics.com .matronics.com/contribution
>
> --
> ************************************* *************************************
> Keith Ashcraft
> ITT Industries
> Advanced Engineering & Sciences
> 5009 Centennial Blvd.
> Colorado Springs, CO
> 80919
> (719) 599-1787 -- work
> (719) 332-4364 -- cell
> keith.ashcraft@itt.com
>
>
>
>
>---------------------------------
> This e-mail and any files transmitted with it may be proprietary and are intended
solely for the use of the individual or entity to whom they are addressed.
If you have received this e-mail in error please notify the sender. Please
note that any views or opinions presented in this e-mail are solely those of the
author and do not necessarily represent those of ITT Corporation. The recipient
should check this e-mail and any attachments for the presence of viruses.
ITT accepts no liability for any damage caused by any virus transmitted by this
e-mail.
>
>
>
> Dave Downey
> Harleysville (SE) PA
> 100 HP Corvair
>
>
>
>---------------------------------
>
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| Subject: | Re: Recommended Wire Stripping Tool |
The Stripmaster I bought and am using is the one from B & C Speciality Products,
Inc. and it's the model 45-097 Ideal Stripmaster.
Used it on Tefzel 16-26 AWG wire, no nicks.
YMMV
Their website location for this tool:
http://www.bandc.biz/cgi-bin/ez-catalog/cat_display.cgi?9X358218
--------
Ron Lendon, Clinton Township, MI
Corvair Zodiac XL, ScrapBuilder ;-)
http://www.mykitlog.com/rlendon
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169940#169940
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| Subject: | Re: 701: Elevator Bellcrank Neutral? |
On Mar 14, 2008, at 6:28 AM, Tony Bonsell wrote:
>
> Hi Guys
>
> I'm installing the pitch control bellcrank 7-C-1-1 to the pitch
> control rod 7-C-1-3 and I can't seem to find a reference to the
> neutral position of the bellcrank. Is it meant to be perpendicular
> to the cabin floor? The rod will end up being a lot shorter than the
> 685mm in the drawings. Jari, you had the same question back last
> summer...
>
> And for that matter, the control stick is meant to be neutral
> according to taste. Without the seat cushions in I can't really get
> a feel for that. Where did you guys start from?
>
Tony:
I am at the same point as you are and have been considering the
problem for about two weeks. My pitch control rod (7C1-3) is 685 mm
long and from the picture in the plans of the Horizontal Tail
Bellcrank (7C1-1) I assume it is to be perpendicular to the cabin
floor. I just checked mine and when it is perpendicular to the floor
the stick is full back and lateral travel is greatly restricted. In
other words, you would be not be able to bank the aircraft to any
degree and would have no up elevator control movement left. With the
Pitch Control Rod at 685 mm and the stick at what I would like as the
neutral; the top of the Horizontal Tail Bellcrank comes in contact
with the seat back channel. I have queried Zenair about this but have
not received a reply yet.
I think you have solved my problem with your question. I now believe
I need to shorten my pitch control rod so that the Horizontal Tail
Bellcrank is perpendicular to the floor when the stick is in what I
want to be my neutral position. That will have to wait until the
cushions are installed or, at the minimum, their dimensions are able
to be simulated with some degree of accuracy.
I stand ready for correction and/or comment.
Sorry to interrupt the stream of speculative comments about accidents.
Stan
N701VG
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| Subject: | Re: Ye Olde Continental |
Bob,
I got to keep moving. Don't want any rust accumulating on these old joints.
Also, I've had 3 offers on my 701.
I am negotiating on a 701 project. The owner, God rest his soul, passed away and
his sone is selling the project.
So if I get to buy the unfinished project, I will have something to do, and possibly
get $5.75 per hour for my labor.....
[quote="NYTerminat(at)aol.com"]Tommy,
Ready to build another so soon?
Bob Spudis
do not archive
--------
Tommy Walker
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=169945#169945
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The "problems" */I/* mentioned could be the results of poor or
inappropriate modifications, inspection or repairs.
When does a problem become "Known"? I picked up the wreckage of a
Bellanca Decathlon that shed a wing while practicing aerobatics. The
wing failure had nothing to do with the wing design, mounting or the way
that it was flown at the time. The root problem was a small crack in
the pilot's seat back, under the glued down upholstery. No one had been
looking there. See NTSB report CHI88FA240, AD 76-22-01, AD 89-18-06.
When did this problem become "Known" 1976? 1989?
We have a couple of incidents where the wing allegedly failed. Evidence
has not allowed a conclusion for the cause to be determined.
Personally, discussion and intelligent thought, and God forbid, putting
forth a "theory" are not necessarily a bad idea. We need to remember
that a "theory" is just a possible explanation for a certain set of
facts, not a conclusion, not a truth and not an accusation.
Yes, we should let the experts do their work. But the expert is not
always the one who discovers the problem, it's cause or sometimes the
fix. Sometimes it is the lowly mechanic. Try asking the FAA a question
and they very likely will first ask "what do you think" Ask Cessna to
approve a repair and the best you get is a "letter of no objection"
(1983 - 1999)
Ballistic parachutes: Our new instructor (a former student of mine)
rode a Cirrus down by parachute after an aileron departed the aircraft.
He does not feel that he would have survived without it. I will install
one.
Back to lurking in my classroom where I will continue to teach my A&P
students to suspect everything until proven airworthy.
Sorry for ranting,
Ken Lilja
Jaybannist@cs.com wrote:
>
> Ken,
>
> Exactly what known problem are you thinking about solving?
>
> Jay in Dallas
>
> Ken Lilja <planes_by_ken@bellsouth.net> wrote:
>
>
>>
>> I am giving thought to installing diagonal ribs between the stock ones.
>> I seem to remember that diagonal ribs are good in torsion. The Ercoupe
>> uses this design. Be careful or random strengthening as this could
>> shift loads to other areas and cause more problems.
>> What I would like to know is if they had wing lockers, what type of
>> aileron hinge and how much attention was given to aileron rigging
>> especially cable tension.
>> Ken Lilja
>>
>> ashontz wrote:
>>
>>>
>>> I agree. The wings are plenty strong in static load. Dynamically, I'm not so
sure. Extra ribs provide extra torsional stability and strength, as well as
actually making the wings stronger in a pure positive or negative load. Shorter
segments to transmit the same load across equals less leverage to crumple the
skins, particularly in compression. Think of a 5' fishing pole with only one
eye at the very end of the pole. Now think of the same pole with an eye every
6 inches. Much stronger under load.
>>>
>>> I would guess that if you could stand next to that inverted Zenith wing when
it was being static tested, and just touched it, it would hobble and bobble
all over the place, possibly even notice a bit of a "slow motion flutter".
>>>
>>>
>>>
>>>
>>
>
>
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Yes, IF I did the modification I would stress test with sandbags on a
proof wing. I did stress testing on a few mods I designed to certified
aircraft (field approval 337). THINKING about a mod is not the same as
doing it. THINKING about a mod is probably the best way to avoid making
a mod. Also, any change is a new design. Reinforced cabin step attach
might effect the rear spar attach. How about a swing down instrument
panel? Access panels in any new location? They all could have
unintended adverse effects.
Ken Lilja
Gig Giacona wrote:
>
> How do you propose to test this new design? Are you going to stress it as the
Zenith design as been stressed?
>
>
> planes_by_ken(at)bellsout wrote:
>
>> I am giving thought to installing diagonal ribs between the stock ones.
>> I seem to remember that diagonal ribs are good in torsion. The Ercoupe
>> uses this design. Be careful or random strengthening as this could
>> shift loads to other areas and cause more problems.
>> What I would like to know is if they had wing lockers, what type of
>> aileron hinge and how much attention was given to aileron rigging
>> especially cable tension.
>> Ken Lilja
>>
>>
>
>
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Larry,
I am very aware of the issues of propagation of stresses in a
structure. My origional post also had this line: "Be careful or random
strengthening as this could shift loads to other areas and cause more
problems." "Thinking" = "Thought experiment" I have picked up too many
aircraft wrecks and had some friends die. I am very conservative in how
I will build my 601.
Ken Lilja
LarryMcFarland wrote:
>
>
> Ken,
> I have to add something here. The idea that you should redesign the
> wings, ribs or anything else is wrong. There is no proven fault in the
> design and the accidents are more likely the cause of poor assembly,
> construction errors or flying error. If you redesign the rib
> structure, you become responsible and
> you can increase the problem you sought to resolve. Structures have
> long and short coupled deflections
> that permit progressive flexing from the outer panels to the inner.
> If you make the wing too rigid, you bring
> force and stresses to the fuselage and structure more quickly that can
> exceed the design. I'd recommend
> you build and respect the plans before considering those changes and
> talk with the designer or Nick
> before doing so.
> My recommendation would be to keep faith with the plans. My hunch is
> that something outside of the
> design will be found that links common problem variations to something
> outside the scope of the plans.
>
> If you want to fund a "finite element design review", send the money
> to Zenith to support the most important
> source of information you have. I'm sure this kind of response would
> be appreciated and say we're all in this together.
>
> Larry McFarland 601HDS at www.macsmachine.com
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