Today's Message Index:
----------------------
1. 05:05 AM - Pitch trimming (Jeff Boatright)
2. 05:22 AM - Re: Pitch trimming (Phillips, Jack)
3. 05:23 AM - Re: Pitch trimming (Isablcorky@aol.com)
4. 05:52 AM - Re: Pitch trimming (Jim Ash)
5. 06:01 AM - Re: Pitch trimming ()
6. 06:09 AM - Re: Pitch trimming (Jack T. Textor)
7. 06:24 AM - pitch trim saved Sean Tucker's life (Michael D Cuy)
8. 07:10 AM - Re: pitch trim saved Sean Tucker's life (Rick Holland)
9. 07:47 AM - Re: pitch trim saved Sean Tucker's life (Jack T. Textor)
10. 08:15 AM - Re: pitch trim saved Sean Tucker's life ()
11. 08:41 AM - Re: Pitch trimming (Rob Stapleton)
12. 09:05 AM - Re: Pitch trimming (Carl Vought)
13. 09:19 AM - Re: Trim tab was pitch trim saved Sean Tucker's life (Hans Vander Voort)
14. 10:56 AM - Re: Pitch trimming (tmbrant1@netzero.com)
15. 01:21 PM - Re: Re: Wing Rib Jig (Eric Williams)
16. 01:21 PM - Re: Pitch trimming (Jeff Boatright)
17. 01:33 PM - Re: Pietenpol (chris cummins)
18. 02:32 PM - Wing rib jigs (Carl Vought)
19. 02:53 PM - Brakes (TBYH@aol.com)
20. 03:51 PM - Re: Broadhead to Oshkosh (Alan Lyscars)
21. 06:20 PM - Re: Brakes (KMHeide)
22. 07:41 PM - Re: Pietenpol (R Matt Doody)
23. 08:07 PM - Re: Pitch trimming (gcardinal)
24. 09:41 PM - Re: Pitch trimming (Rcaprd@aol.com)
Message 1
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--> Pietenpol-List message posted by: Jeff Boatright <jboatri@emory.edu>
We've been trying to get the Piet to fly hands-off. Currently it
tends to nose down. We thought tried to lower the stabilizer leading
edge / raise the trailing edge, but could not move it much at all due
to the rudder being hinged on both the vertical fin and the rear post
of the fuselage.
Next step was to put twist into the stabilizer by cranking on the
turnbuckles. This put an easily-seen front-to-rear upturn on the
stabilizer. Flight testing showed that this helped - we're having to
hold about half the back stick that we had to before. However, the
plane still wants to nose down.
Next step? We could crank in more stabilizer twist. Do you know if
there is a safety limit to how much twist can be put in? I guess
another solution would be trim tabs.
I searched the archives on "trim" and "stabilizer" and couldn't come
up with an answer.
Thanks for any thoughts on the subject,
Jeff
Message 2
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--> Pietenpol-List message posted by: "Phillips, Jack" <Jack.Phillips@cardinal.com>
You could try the old bungee cord on the stick approach - a short bungee
cord pulling back on the stick, with a sliding ring that can be moved up
or down the stick as required to apply the correct spring force.
I installed a spring assist trim system similar to Mike Cuy's on mine,
with a set of springs pulling on the elevator bellcrank in the fuselage.
Spring tension can be adjusted with a lever in the cockpit. Works
great.
Jack Phillips
NX899JP
Raleigh, NC
-----Original Message-----
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Jeff
Boatright
Sent: Tuesday, April 25, 2006 8:02 AM
Subject: Pietenpol-List: Pitch trimming
--> Pietenpol-List message posted by: Jeff Boatright <jboatri@emory.edu>
We've been trying to get the Piet to fly hands-off. Currently it
tends to nose down. We thought tried to lower the stabilizer leading
edge / raise the trailing edge, but could not move it much at all due
to the rudder being hinged on both the vertical fin and the rear post
of the fuselage.
Next step was to put twist into the stabilizer by cranking on the
turnbuckles. This put an easily-seen front-to-rear upturn on the
stabilizer. Flight testing showed that this helped - we're having to
hold about half the back stick that we had to before. However, the
plane still wants to nose down.
Next step? We could crank in more stabilizer twist. Do you know if
there is a safety limit to how much twist can be put in? I guess
another solution would be trim tabs.
I searched the archives on "trim" and "stabilizer" and couldn't come
up with an answer.
Thanks for any thoughts on the subject,
Jeff
Cardinal Health -- Working together. For life. (sm)
This message is for the designated recipient only and may contain privileged, proprietary,
or otherwise private information. If you have received it in error,
please notify the sender immediately and delete the original. Any other use
of the email by you is prohibited.
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Message 3
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Subject: | Re: Pitch trimming |
Jeff,
Had the same experience with 41CC in the beginning. Forward 16 gal fuel
tank, 22lb metal prop and a 140 lb test pilot. When he released the stick it nose
dived. We twixed the hor stab, ( eyeballed it so it lined up with lower edge
of engine rocker covers). That helped some. I Africanized a trim tab. Took a
flat rubber hold down strap about a foot long. Anchored both ends to front of
seat so it was just loose when wrapped around the bottom of the stick. As
rear pressure was needed merely slide the rubber strap up the stick until
everything equalized. If you forget to lower the strap on landing don't worry
as
you can override it's pressure. It is a way of solving your little problem.
Another solution is have your pilot eat more Louisiana Crawfish.
Message 4
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--> Pietenpol-List message posted by: Jim Ash <ashcan@earthlink.net>
I've flow with spring-assisted systems in gliders and they work ok. My two concerns
are that you're effectively applying continuous pressure to the whole system
from the stick all the way back to the elevator, which I'm not convinced would
contribute to premature wear to the bushings and bearings in the middle of
it all. Assuming you just bungee the stick, do you have enough travel left to
be able to fly it safely? This is another argument against applying extra forces
up front. Trim tabs or a re-arrangement of your tail feathers wouldn't have
this same effect.
My second concern is that if something happens to your elevator linkage system,
you're screwd in a big way. I've certainly flown a good number of aircraft in
which this is a risk, but an airplane of mine will have some kind of independent
trim system which can be used independently of the primary elevator linkage.
Granted, a Piet doesn't have this by design, but mine will. Most commonly used
are flying trim systems or some kind of adjustment to the horizontal stabilizer
like the jack screw in my J-3.
Jim Ash
-----Original Message-----
>From: "Phillips, Jack" <Jack.Phillips@cardinal.com>
>Sent: Apr 25, 2006 8:21 AM
>To: pietenpol-list@matronics.com
>Subject: RE: Pietenpol-List: Pitch trimming
>
>--> Pietenpol-List message posted by: "Phillips, Jack" <Jack.Phillips@cardinal.com>
>
>You could try the old bungee cord on the stick approach - a short bungee
>cord pulling back on the stick, with a sliding ring that can be moved up
>or down the stick as required to apply the correct spring force.
>
>I installed a spring assist trim system similar to Mike Cuy's on mine,
>with a set of springs pulling on the elevator bellcrank in the fuselage.
>Spring tension can be adjusted with a lever in the cockpit. Works
>great.
>
>Jack Phillips
>NX899JP
>Raleigh, NC
>
>-----Original Message-----
>From: owner-pietenpol-list-server@matronics.com
>[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Jeff
>Boatright
>Sent: Tuesday, April 25, 2006 8:02 AM
>To: pietenpol-list@matronics.com
>Subject: Pietenpol-List: Pitch trimming
>
>--> Pietenpol-List message posted by: Jeff Boatright <jboatri@emory.edu>
>
>We've been trying to get the Piet to fly hands-off. Currently it
>tends to nose down. We thought tried to lower the stabilizer leading
>edge / raise the trailing edge, but could not move it much at all due
>to the rudder being hinged on both the vertical fin and the rear post
>of the fuselage.
>
>Next step was to put twist into the stabilizer by cranking on the
>turnbuckles. This put an easily-seen front-to-rear upturn on the
>stabilizer. Flight testing showed that this helped - we're having to
>hold about half the back stick that we had to before. However, the
>plane still wants to nose down.
>
>Next step? We could crank in more stabilizer twist. Do you know if
>there is a safety limit to how much twist can be put in? I guess
>another solution would be trim tabs.
>
>I searched the archives on "trim" and "stabilizer" and couldn't come
>up with an answer.
>
>Thanks for any thoughts on the subject,
>
>Jeff
>
>
>
>
>
>
>
>Cardinal Health -- Working together. For life. (sm)
>_________________________________________________
>
>This message is for the designated recipient only and may contain privileged,
proprietary, or otherwise private information. If you have received it in error,
please notify the sender immediately and delete the original. Any other use
of the email by you is prohibited.
>
>Dansk - Deutsch - Espanol - Francais - Italiano - Japanese - Nederlands - Norsk - Portuguese - Svenska: www.cardinalhealth.com/legal/email
>
>
>
>
>
>
>
Message 5
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--> Pietenpol-List message posted by: <harvey.rule@bell.ca>
Don't forget,your engine is already in a nose down attitude.Don't let
this throw you off.
-----Original Message-----
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Jeff
Boatright
Sent: April 25, 2006 8:02 AM
Subject: Pietenpol-List: Pitch trimming
--> Pietenpol-List message posted by: Jeff Boatright <jboatri@emory.edu>
We've been trying to get the Piet to fly hands-off. Currently it
tends to nose down. We thought tried to lower the stabilizer leading
edge / raise the trailing edge, but could not move it much at all due
to the rudder being hinged on both the vertical fin and the rear post
of the fuselage.
Next step was to put twist into the stabilizer by cranking on the
turnbuckles. This put an easily-seen front-to-rear upturn on the
stabilizer. Flight testing showed that this helped - we're having to
hold about half the back stick that we had to before. However, the
plane still wants to nose down.
Next step? We could crank in more stabilizer twist. Do you know if
there is a safety limit to how much twist can be put in? I guess
another solution would be trim tabs.
I searched the archives on "trim" and "stabilizer" and couldn't come
up with an answer.
Thanks for any thoughts on the subject,
Jeff
Message 6
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--> Pietenpol-List message posted by: "Jack T. Textor" <jtextor@thepalmergroup.com>
Jack,
Do you have any pictures of the arrangement?
Jack Textor
You could try the old bungee cord on the stick approach - a short bungee
cord pulling back on the stick, with a sliding ring that can be moved up
or down the stick as required to apply the correct spring force.
I installed a spring assist trim system similar to Mike Cuy's on mine,
with a set of springs pulling on the elevator bellcrank in the fuselage.
Spring tension can be adjusted with a lever in the cockpit. Works
great.
Jack Phillips
NX899JP
Raleigh, NC
Message 7
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Subject: | pitch trim saved Sean Tucker's life |
--> Pietenpol-List message posted by: Michael D Cuy <Michael.D.Cuy@grc.nasa.gov>
There is a very impressive press conference video of Sean describing his
entire ordeal a few weeks ago at the bottom of this newswire
from AvWeb. The guy is one impressive person.
Mike C.
http://www.avweb.com/eletter/archives/avflash/609-full.html
Message 8
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Subject: | Re: pitch trim saved Sean Tucker's life |
Thoughts of losing elevator control like this guy did is the reason that I
have thought of installing independent elevator trim as you see on Pipers
and Cessnas. Have even looked at the Mac electronic trim servos, just a big
RC servo that would fit inside one of the flippers with 3 wires running up
to the cockpit. Landing with only trim control wouldn't be fun but
preferable to bailing out with no parachute.
Rick H.
On 4/25/06, Michael D Cuy <Michael.D.Cuy@grc.nasa.gov> wrote:
>
> --> Pietenpol-List message posted by: Michael D Cuy <
> Michael.D.Cuy@grc.nasa.gov>
>
>
> There is a very impressive press conference video of Sean describing his
> entire ordeal a few weeks ago at the bottom of this newswire
>
> from AvWeb. The guy is one impressive person.
>
> Mike C.
>
> http://www.avweb.com/eletter/archives/avflash/609-full.html
>
>
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>
>
--
Rick Holland
"Logic is a wreath of pretty flowers, that smell bad"
Message 9
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Subject: | pitch trim saved Sean Tucker's life |
Rick,
I too have considered the MAC. My RV 8 had one, they were great. The
problem is the thickness of the Piets H-Stab is not enough to completely
house the servo. Also the Stabs are not directly tied together.
Jack Textor
Thoughts of losing elevator control like this guy did is the reason that
I have thought of installing independent elevator trim as you see on
Pipers and Cessnas. Have even looked at the Mac electronic trim servos,
just a big RC servo that would fit inside one of the flippers with 3
wires running up to the cockpit. Landing with only trim control wouldn't
be fun but preferable to bailing out with no parachute.
Rick H.
Message 10
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Subject: | pitch trim saved Sean Tucker's life |
How bout having two individual control sticks,one for one side of the
elevator and one for the other.That would make for some interesting
flying eh!
________________________________
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Jack T.
Textor
Sent: April 25, 2006 10:47 AM
Subject: RE: Pietenpol-List: pitch trim saved Sean Tucker's life
Rick,
I too have considered the MAC. My RV 8 had one, they were great. The
problem is the thickness of the Piets H-Stab is not enough to completely
house the servo. Also the Stabs are not directly tied together.
Jack Textor
Thoughts of losing elevator control like this guy did is the reason that
I have thought of installing independent elevator trim as you see on
Pipers and Cessnas. Have even looked at the Mac electronic trim servos,
just a big RC servo that would fit inside one of the flippers with 3
wires running up to the cockpit. Landing with only trim control wouldn't
be fun but preferable to bailing out with no parachute.
Rick H.
Message 11
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--> Pietenpol-List message posted by: "Rob Stapleton" <foto@alaska.net>
I am no expert on aeronautical engineering but as a photographer I have seen
plenty of aircraft with aluminum tabs added to the elevator that are bent at
angles to correct pitch in level flight. I am not sure about the strength of
these into a wooden elevator? Any comments on this? Too simple?
Rob
-----Original Message-----
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Jeff
Boatright
Sent: Tuesday, April 25, 2006 4:02 AM
Subject: Pietenpol-List: Pitch trimming
--> Pietenpol-List message posted by: Jeff Boatright <jboatri@emory.edu>
We've been trying to get the Piet to fly hands-off. Currently it
tends to nose down. We thought tried to lower the stabilizer leading
edge / raise the trailing edge, but could not move it much at all due
to the rudder being hinged on both the vertical fin and the rear post
of the fuselage.
Next step was to put twist into the stabilizer by cranking on the
turnbuckles. This put an easily-seen front-to-rear upturn on the
stabilizer. Flight testing showed that this helped - we're having to
hold about half the back stick that we had to before. However, the
plane still wants to nose down.
Next step? We could crank in more stabilizer twist. Do you know if
there is a safety limit to how much twist can be put in? I guess
another solution would be trim tabs.
I searched the archives on "trim" and "stabilizer" and couldn't come
up with an answer.
Thanks for any thoughts on the subject,
Jeff
Message 12
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Subject: | Re: Pitch trimming |
--> Pietenpol-List message posted by: "Carl Vought" <carbarvo@knology.net>
I've been wondering the same thing. I don't think I've ever seen a Piet with
a "bendable" trim tab. Have I just not been looking hard enough?....Carl
Vought
----- Original Message -----
From: "Rob Stapleton" <foto@alaska.net>
Sent: Tuesday, April 25, 2006 10:40 AM
Subject: RE: Pietenpol-List: Pitch trimming
> --> Pietenpol-List message posted by: "Rob Stapleton" <foto@alaska.net>
>
> I am no expert on aeronautical engineering but as a photographer I have
> seen
> plenty of aircraft with aluminum tabs added to the elevator that are bent
> at
> angles to correct pitch in level flight. I am not sure about the strength
> of
> these into a wooden elevator? Any comments on this? Too simple?
> Rob
>
> -----Original Message-----
> From: owner-pietenpol-list-server@matronics.com
> [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Jeff
> Boatright
> Sent: Tuesday, April 25, 2006 4:02 AM
> To: pietenpol-list@matronics.com
> Subject: Pietenpol-List: Pitch trimming
>
> --> Pietenpol-List message posted by: Jeff Boatright <jboatri@emory.edu>
>
> We've been trying to get the Piet to fly hands-off. Currently it
> tends to nose down. We thought tried to lower the stabilizer leading
> edge / raise the trailing edge, but could not move it much at all due
> to the rudder being hinged on both the vertical fin and the rear post
> of the fuselage.
>
> Next step was to put twist into the stabilizer by cranking on the
> turnbuckles. This put an easily-seen front-to-rear upturn on the
> stabilizer. Flight testing showed that this helped - we're having to
> hold about half the back stick that we had to before. However, the
> plane still wants to nose down.
>
> Next step? We could crank in more stabilizer twist. Do you know if
> there is a safety limit to how much twist can be put in? I guess
> another solution would be trim tabs.
>
> I searched the archives on "trim" and "stabilizer" and couldn't come
> up with an answer.
>
> Thanks for any thoughts on the subject,
>
> Jeff
>
>
>
Message 13
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Subject: | Re: Trim tab was pitch trim saved Sean Tucker's life |
--> Pietenpol-List message posted by: Hans Vander Voort <hans.vander.voort@alfalaval.com>
Rick,
The only problem I see with this is that the Elevator flippers are not
connected (no torque tube)
Thus you trim only one flipper and not the other.
Unless of course you place servos in both.
Same for aluminum trim tabs
Further the elevator cables are 3/32 with a strength of 1000+ Lbs.
With a 1 : 5 ratio on your stick you will need to put 200 Lbs of force on
the stick to break something.
The only way you will such high stress on the tail surfaces is during
aerobatics (better bring a parachute)
Hans
Message 14
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Subject: | Re: Pitch trimming |
--> Pietenpol-List message posted by: "tmbrant1@netzero.com" <tmbrant1@netzero.net>
Bill Rewey (I believe) has an aluminum tab on his Piet - it's the Navy painted
one you've probably seen before. I don't think he's on the list. In addition
to that he's got a bungee cord with an Adel clamp around the stick which is slid
up and down as needed for trim.
Tom B.
Message 15
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Subject: | Re: Wing Rib Jig |
--> Pietenpol-List message posted by: "Eric Williams" <ewilliams805@msn.com>
I've got a set of wing ribs that I'll sell you for $150 if you are
interested in them. They are somewhere around 10 years old and were owned
by others before me so I can't testify to anything about the building
process other than that I know they are Douglas Fir and were glued with West
System epoxy. I had pictures on Barnstormers as part of the ad where I was
trying to sell the project as a whole with ribs, tail feathers, and fuselage
but no one bought it and the ad has expired. I guess I'll sell it all
separately if that works better.
Email me off-list if you (or anyone else) has any interest and I can email
pictures back to you.
Thanks.
Eric
>From: "plncrzy" <plncrzy3@netscape.net>
>To: pietenpol-list@matronics.com
>Subject: Pietenpol-List: Re: Wing Rib Jig
>Date: Thu, 20 Apr 2006 16:22:20 -0700
>
>--> Pietenpol-List message posted by: "plncrzy" <plncrzy3@netscape.net>
>
>OK, so by the over whelming response I will be building my own wing rib
>jig. The thought, by buying one already made was not because I couldn't do
>it, I was just trying to save some time. I now see the logic in building
>and keeping my own jig. Next Question? Is there any difference or benefit
>by either soaking or steaming your capstrips, does one work any better than
>the other. Thanks Again for the help and support. Bryan
>
>
>Read this topic online here:
>
>http://forums.matronics.com/viewtopic.php?p=29734#29734
>
>
Message 16
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Subject: | Re: Pitch trimming |
Cc: Boatright1@aol.com, FWWhitaker@worldnet.att.net
--> Pietenpol-List message posted by: Jeff Boatright <jboatri@emory.edu>
Thanks for all the thoughts on this, and please keep them coming.
Our Piet had a huge trim tab, but for the opposite problem. The
former owner mainly flew solo and was a big, tall guy. He had
problems with nose up, not nose down. Obviously we could have left
the tab on and simply bent it the other way, but it was so huge and
ugly (and only on one elevator!) that we pulled it off. Even solo
we're getting nose down, so we still need a trim solution.
At 11:04 AM -0500 4/25/06, Carl Vought wrote:
>--> Pietenpol-List message posted by: "Carl Vought" <carbarvo@knology.net>
>
>I've been wondering the same thing. I don't think I've ever seen a
>Piet with a "bendable" trim tab. Have I just not been looking hard
>enough?....Carl Vought
>----- Original Message ----- From: "Rob Stapleton" <foto@alaska.net>
>To: <pietenpol-list@matronics.com>
>Sent: Tuesday, April 25, 2006 10:40 AM
>Subject: RE: Pietenpol-List: Pitch trimming
>
>>--> Pietenpol-List message posted by: "Rob Stapleton" <foto@alaska.net>
>>
>>I am no expert on aeronautical engineering but as a photographer I have seen
>>plenty of aircraft with aluminum tabs added to the elevator that are bent at
>>angles to correct pitch in level flight. I am not sure about the strength of
>>these into a wooden elevator? Any comments on this? Too simple?
>>Rob
>>
>>-----Original Message-----
>>From: owner-pietenpol-list-server@matronics.com
>>[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Jeff
>>Boatright
>>Sent: Tuesday, April 25, 2006 4:02 AM
>>To: pietenpol-list@matronics.com
>>Subject: Pietenpol-List: Pitch trimming
>>
>>--> Pietenpol-List message posted by: Jeff Boatright <jboatri@emory.edu>
>>
>>We've been trying to get the Piet to fly hands-off. Currently it
>>tends to nose down. We thought tried to lower the stabilizer leading
>>edge / raise the trailing edge, but could not move it much at all due
>>to the rudder being hinged on both the vertical fin and the rear post
>>of the fuselage.
>>
>>Next step was to put twist into the stabilizer by cranking on the
>>turnbuckles. This put an easily-seen front-to-rear upturn on the
>>stabilizer. Flight testing showed that this helped - we're having to
>>hold about half the back stick that we had to before. However, the
>>plane still wants to nose down.
>>
>>Next step? We could crank in more stabilizer twist. Do you know if
>>there is a safety limit to how much twist can be put in? I guess
>>another solution would be trim tabs.
>>
>>I searched the archives on "trim" and "stabilizer" and couldn't come
>>up with an answer.
>>
>>Thanks for any thoughts on the subject,
>>
>>Jeff
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
--
Jeffrey H. Boatright, PhD
Associate Professor, Emory Eye Center, Atlanta, GA, USA
Senior Editor, Molecular Vision, http://www.molvis.org/molvis
mailto:jboatri@emory.edu
Message 17
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Matt, You are correct in your observations. What else would you like to know. I'll
see if I can answer your questions.
Chris Cummins 516BC
---------------------------------
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The recent interest in rib jigs, staples vs nails, etc.has prompted me to post
a picture of a rib jig I made while building an Airbike wing. I didnt use nails
or staples. Instead, I held everything in place with toggle clamps. What I like
about this method is that you can put the gussets on both sides at the same
time...Cuts glue-drying time in half. The price you pay is that the gussets
need to be cut very uniformly, which you can do by stacking the layers of ply
and using a metal template on the top of the stack. Carl Vought
Message 19
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I'm looking in to various go-kart brakes for my Piet and just wondering what
most of you use -- the mechanically actuated disc brakes, or the hydraulic
juice brake calipers. I see advantages/disadvantages to both and wanted to see
what all of the experts have to say! I'm building the Jenny-style landing gear
and will use disc brakes -- just wondering if mechanical or juice...
Got all the tail feathers finished over the weekend -- less hinges (will
install those tonight). Came out nice and light...then I'll get the fuselage down
from the ceiling joists and start putting landing gear together...
Hey, less than 90 days to Brodhead!
Fred B.
La Crosse, WI
Message 20
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Subject: | Re: Broadhead to Oshkosh |
Dear Brian,
I can at least speak for OSH. I took my oldest to Airventure in 2003 (he was 13
yrs old). We borrowed my buddy's pop-up camper and camped at Camp Schoeller.
No kidding: there were at least 20,000 other tents/pop-ups/5th wheels/drive-arounds/mobile
palaces at Camp Shoeller that week. At first, we felt alone-not
knowing anyone else out there. Like most campground camping experiences, as
the week progressed, we came to know the campers around us. After a big day
inhaling aircraft in the sun, we'd retreat to, what we came to call, home and
fire the grill for steaks and corn.
So camping at OSH is not a trout-filled dream. But it's a great place to hang
your hat and meet fellow aviation nuts like us.
Alan
----- Original Message -----
From: brian jardine
To: pietenpol-list@matronics.com
Sent: Monday, April 24, 2006 2:57 PM
Subject: Pietenpol-List: Broadhead to Oshkosh
Group,
I am planning a cross-country trip (driving) from Utah to Broadhead, and then
on to Air Adventure at Oshkosh. I am bringing my 3 young boys, 12, 9, and 5.
Earth Day
Message 21
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Say Fred,
Have you looked at the new mountain bikes with front disc brake set-up They have
an internal spring that return the brake back to the open without any exposed
brake springs. The disc is bolted onto a spindle which could be taken off
and applied to our piets.....Just a thought but looks and seems very promising
and no need for a return spring on the toe pedal....
Any other thoughts.....
Ken
TBYH@aol.com wrote:
I'm looking in to various go-kart brakes for my Piet and just wondering what
most of you use -- the mechanically actuated disc brakes, or the hydraulic
juice brake calipers. I see advantages/disadvantages to both and wanted to see
what all of the experts have to say! I'm building the Jenny-style landing gear
and will use disc brakes -- just wondering if mechanical or juice...
Got all the tail feathers finished over the weekend -- less hinges (will install
those tonight). Came out nice and light...then I'll get the fuselage down
from the ceiling joists and start putting landing gear together...
Hey, less than 90 days to Brodhead!
Fred B.
La Crosse, WI
---------------------------------
Message 22
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Chris,
Thanks for responding.
I am currently working on another project however I have an interest in building
a Piet as a next project. What are the dimensions on the cant for the cabanes
and what tubing sizes did you use for the empennage? What other changes
have you made? Do you plan on creating a website show-casing your Piet and its
unique features?
Best Regards,
Matt
chris cummins <cccstandard@yahoo.com> wrote:
Matt, You are correct in your observations. What else would you like to know.
I'll see if I can answer your questions.
Chris Cummins 516BC
---------------------------------
---------------------------------
Message 23
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Subject: | Re: Pitch trimming |
--> Pietenpol-List message posted by: "gcardinal" <gcardinal@mn.rr.com>
Jeff,
We had the same problem with NX18235 when it first flew. It required about 6
lbs. of aft stick pressure to maintain level flight.
One problem we found was the elevators were rigged slightly uneven. When
this was corrected the required aft stick pressure was reduced to about 2
lbs. The remaining trimming was taken care of by adjusting the stabilizer
turnbuckles.
Greg Cardinal
----- Original Message -----
From: "Jeff Boatright" <jboatri@emory.edu>
Sent: Tuesday, April 25, 2006 7:01 AM
Subject: Pietenpol-List: Pitch trimming
> --> Pietenpol-List message posted by: Jeff Boatright <jboatri@emory.edu>
>
> We've been trying to get the Piet to fly hands-off. Currently it tends to
> nose down. We thought tried to lower the stabilizer leading edge / raise
> the trailing edge, but could not move it much at all due to the rudder
> being hinged on both the vertical fin and the rear post of the fuselage.
>
> Next step was to put twist into the stabilizer by cranking on the
> turnbuckles. This put an easily-seen front-to-rear upturn on the
> stabilizer. Flight testing showed that this helped - we're having to hold
> about half the back stick that we had to before. However, the plane still
> wants to nose down.
>
> Next step? We could crank in more stabilizer twist. Do you know if there
> is a safety limit to how much twist can be put in? I guess another
> solution would be trim tabs.
>
> I searched the archives on "trim" and "stabilizer" and couldn't come up
> with an answer.
>
> Thanks for any thoughts on the subject,
>
> Jeff
>
>
> http://www.matronics.com/Navigator?Pietenpol-List
> http://wiki.matronics.com
>
>
>
Message 24
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Subject: | Re: Pitch trimming |
First, a few observations:
The Pietenpol Airfoil has a LOT of negative pitching moment, requiring
more down force on the tail than other types of airfoils, which is another one
of the things that cause this type airframe to be very draggy. Trim drag is
the amount of Down force applied to the tail, to maintain level flight at a
particular power setting. Another thing that aggravates the negative pitching
moment, is the actual weight of the flippers, which adds to the nose down
characteristic.
The pitch axis is dynamic on Pietenpols, similar to any other aircraft,
in that trim drag changes with changes in C of G. If you carried all of your
fuel in the wing (as designed), the C of G changes very little, hence, no need
for adjustable pitch trim.
Choices:
Adjusting the leading edge of the stabilizer down, to attain a nose up
attitude would be a ground adjustable trim method. If you use a cowling fuel tank,
an in flight adjustable trim tab, or some type of spring / bunji applied to
either the bell crank, or the stick, may be used. In my mind, I don't like
anything extra - if it ain't there, it can't break...kiss method.
I had similar characteristics as you (and many others), in that I had to
hold back stick, to maintain level flight when the C of G was at the forward
positions - full cowl tank. The thing I did was to experiment with a Fixed
trim tab on the inboard trailing edge of each flipper. This negates the weight
of the flippers, and has no moving parts. I used balsa wood trailing edge of
R. C. airplanes, available at hobby stores. Each one is about 5" long, and 1
1/2" wide, and blended right into the trailing edge of the flipper. I
experimented with the angle of the trim tab, and after many test flights, found
an
angle that would be hands off, with the C of G in the mid to forward range. To
make dynamic pitch trim changes, I simply adjust the power setting. I have
pictures of my trim tabs here : http://nx770cg.com/Fuselage.html
Chuck G.
NX770CG
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