A aviation & planes forum. AviationBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » AviationBanter forum » rec.aviation newsgroups » Owning
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Cherokee Electric Pitch Trim



 
 
Thread Tools Display Modes
  #1  
Old November 18th 04, 02:08 AM
Jonathan Goodish
external usenet poster
 
Posts: n/a
Default Cherokee Electric Pitch Trim

I have a 1977 Archer II with factory-installed electric pitch trim. The
trim servo motor works in both directions, but it doesn't work well for
moving the cables. When the ambient temperature is warm, the electric
trim works acceptably but occasionally seems to "slip," and when it's
cold, I can forget about it. The manual trim wheel seems to have smooth
movement regardless of temperature, though it is a bit stiff in
extremely cold temperatures. When I run the electric trim, even in warm
temperatures, I can literally place my finger on the trim wheel and get
it to slip.

I do have the Piper maintenance manuals for the airplane, but it appears
that the maintenance manual for the electric trim system is not included
for the Archer II. I assume that either the servo clutch is bad or the
jack screw needs to be disassembled, cleaned, and reassembled due to too
much resistance (though the manual trim wheel is not hard to move).

Does anyone have a suggestion, or know where I can locate the
maintenance manual?



Thanks,
JKG
  #2  
Old November 18th 04, 03:08 AM
Michelle P
external usenet poster
 
Posts: n/a
Default

JKG,
The clutch needs work. Have the servo/clutch unit removed and sent out.
Michelle

Jonathan Goodish wrote:

I have a 1977 Archer II with factory-installed electric pitch trim. The
trim servo motor works in both directions, but it doesn't work well for
moving the cables. When the ambient temperature is warm, the electric
trim works acceptably but occasionally seems to "slip," and when it's
cold, I can forget about it. The manual trim wheel seems to have smooth
movement regardless of temperature, though it is a bit stiff in
extremely cold temperatures. When I run the electric trim, even in warm
temperatures, I can literally place my finger on the trim wheel and get
it to slip.

I do have the Piper maintenance manuals for the airplane, but it appears
that the maintenance manual for the electric trim system is not included
for the Archer II. I assume that either the servo clutch is bad or the
jack screw needs to be disassembled, cleaned, and reassembled due to too
much resistance (though the manual trim wheel is not hard to move).

Does anyone have a suggestion, or know where I can locate the
maintenance manual?



Thanks,
JKG



--

Michelle P ATP-ASEL, CP-AMEL, and AMT-A&P

"Elisabeth" a Maule M-7-235B (no two are alike)

Volunteer Pilot, Angel Flight Mid-Atlantic

Volunteer Builder, Habitat for Humanity

  #3  
Old November 18th 04, 03:16 AM
Roy Page
external usenet poster
 
Posts: n/a
Default

I bought a 77 Archer in July and had exactly the same problem.
Mine would only power trim in one direction and the trim wheel was stiff to
turn by hand..
Most likely it just needs a fine adjustment of the castle nut on top of the
friction drive clutch.
I worked the trim switch on the yoke while my A&P did small adjustments, one
flat of the nut at a time, until it was working great in both directions and
silky smooth when trimmed by hand. Put the cotter pin back in and job was
done in about 30 minutes.
Later I did clean and grease the jack screw at the tail because it was
pretty dry.
--
Roy
N5804F - PA28-181

"Jonathan Goodish" wrote in message
...
I have a 1977 Archer II with factory-installed electric pitch trim. The
trim servo motor works in both directions, but it doesn't work well for
moving the cables. When the ambient temperature is warm, the electric
trim works acceptably but occasionally seems to "slip," and when it's
cold, I can forget about it. The manual trim wheel seems to have smooth
movement regardless of temperature, though it is a bit stiff in
extremely cold temperatures. When I run the electric trim, even in warm
temperatures, I can literally place my finger on the trim wheel and get
it to slip.

I do have the Piper maintenance manuals for the airplane, but it appears
that the maintenance manual for the electric trim system is not included
for the Archer II. I assume that either the servo clutch is bad or the
jack screw needs to be disassembled, cleaned, and reassembled due to too
much resistance (though the manual trim wheel is not hard to move).

Does anyone have a suggestion, or know where I can locate the
maintenance manual?



Thanks,
JKG



  #4  
Old November 18th 04, 03:34 AM
external usenet poster
 
Posts: n/a
Default

On Thu, 18 Nov 2004 01:08:53 GMT, Jonathan Goodish
wrote:

I do have the Piper maintenance manuals for the airplane, but it appears
that the maintenance manual for the electric trim system is not included
for the Archer II. I assume that either the servo clutch is bad or the
jack screw needs to be disassembled, cleaned, and reassembled due to too
much resistance (though the manual trim wheel is not hard to move).

Does anyone have a suggestion, or know where I can locate the
maintenance manual?


Assuming that the trim servo in question is not part of an installed
autopilot with pitch/trim authority, it is probably a PET-1 servo
(Piper Electric Trim).

Have you verified that the clutch is slipping, as opposed to the cable
slipping on the capstan? Both are typical problems.

The servo is simple and easy to repair, finding parts and a manual is
a lot more difficult than "fixing" it. This data is not in the
maintenance manual/IPC.

I know of several sources for this information, but unfortunately they
rely on repairing these units as a source of income.

TC
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Ramifications of Cherokee Trim Jackcrew Failure Bob Chilcoat Home Built 23 June 9th 04 02:48 AM
Ramifications of Cherokee Trim Jackcrew Failure Bob Chilcoat Owning 18 June 9th 04 02:48 AM
Lance vx. 6/300 Bridgadoon Owning 27 September 28th 03 08:20 PM
ALTRAK pitch system flight report optics student Home Built 2 September 21st 03 11:49 PM
Propellor pitch ... Bob Noel Owning 2 July 29th 03 04:30 AM


All times are GMT +1. The time now is 02:12 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 AviationBanter.
The comments are property of their posters.