Re: PT-19 tailwheel shimmy

robert hensarling · Post by **robert hensarling** » Mon Nov 05, 2001 7:37 am

'I'm having a heck of a time with my tailwheel. When I received the airplane
last year I got about 10 landings out of it, and the tailwheel started
shimmying. I found that the strut was packed with grease and not fluid.
Anyway, to make a long story short, I sent the tailwheel off to two
different places for a overhaul. One place had the yoke collar metalized,
but this only lasted an additional 10 landings, then the shimmy was back.
Then I sent the unit to another guy in Kentucky for a complete overhaul, and
he did a beautiful job of refitting and putting it all back together, but it
also lasted about 10 landings, and the shimmy is back. I have the
six-spline type, so maybe this is (or is not ) part of the problem.
Any ideas would be helpful. So far the down time has been 4 months, and the
cost just under a grand, so I'm open to suggestions. One note, both guys I
sent the assembly to did offer to take it back and try again, but I'm just
thinking that maybe this unit can't be fixed. Is there another assembly out
there for sale?
Thanks guys,
Robert Hensarling
http://www.mesquiterocker.com
Uvalde, Texas'

Gene Lehman · Post by **Gene Lehman** » Mon Nov 05, 2001 5:51 pm

'Buy the Russ Harmuth tailwheel conversion. 800-304-7371 It will help greatly and sometimes eliminates the shimmy. It is a long standing problem with the Fairchild that we all fight. Check the attach pints in the fuselage as they tend to break with lost of shimming.

For what it's worth.

Gene

[Non-text portions of this message have been removed]'

robert hensarling · Post by **robert hensarling** » Mon Nov 05, 2001 7:18 pm

'-----Original Message-----
From: Gene Lehman
To: fairchildclub@yahoogroups.com
Date: Monday, November 05, 2001 5:51 PM
Subject: Re: [fairchildclub] PT-19 tailwheel shimmy

Hi Gene. Yep, I already have Russ's conversion. The trunion has been
machined and is a really snug fit. Everything is tight, pins, bolts, etc.
Except::: There's about 1/16th" play in the splines (mine is one of those
heavy-duty looking 6 spline gizmos). I'm guessing that's where the shimmy
starts, but I don't know. If that's the problem area, It's going to be hard
to fix. Maybe the guys with the two splines are better off. What say ye
Mr. Treat??
Robert

>Buy the Russ Harmuth tailwheel conversion. 800-304-7371 It will help

greatly and sometimes eliminates the shimmy. It is a long standing problem
with the Fairchild that we all fight. Check the attach pints in the
fuselage as they tend to break with lost of shimming.

>
>For what it's worth.
>
>Gene
>
>
>[Non-text portions of this message have been removed]
>
>
>To unsubscribe from this group, send an email to:
>fairchildclub-unsubscribe@yahoogroups.com
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>

'

jstreat360@aol.com · Post by **jstreat360@aol.com** » Mon Nov 05, 2001 8:03 pm

'Robert,

Give Joe Denest a call, The PT man. I can't see that little of play in the
splines giving that much shimmy. Quick question, how bad out of balance is
the tire/tube assembly.

Jamie S. Treat A&P/IA

Visit my Web Site:
http://hometown.aol.com/ftreat9191/AIRCRAFTRESTORATIONREPAIRindex.html">Aircraft Restoration & Repair

Meet my Family
http://hometown.aol.com/ftreat9191/TreatFamilyHomePage.html">Treat Family Home Page

[Non-text portions of this message have been removed]'

Gene Lehman · Post by **Gene Lehman** » Mon Nov 05, 2001 9:22 pm

'Waco tail wheels do not shimmy. Maybe we need to convert them all to something like it. Fairchild obviously did not make them for pavement... I have seen a F24 with a Maul tailwheel? UGLY...But it did not shimmy.

Gene

[Non-text portions of this message have been removed]'

bt13a@earthlink.net · Tue Nov 06, 2001 12:11 pm

'You said the trunion has been machined and is tight...I assume you
mean where it mates with the strut. The key is whether the trunnion
has any vertical play between the fork and the strut flange. If so,
try a thin washer made from plastic or brass.

I'm not sure if the spline play will cause shimmy, but try using a
bunch of very heavy grease to see if it helps. That would be a good
indicator if it's the splines.

I think the root of the Fairchild tailwheel shimmy problem is that the
strut angle is too vertical.

Curt Kinchen

--- In fairchildclub@y..., "robert hensarling" wrote:
>
> -----Original Message-----
> From: Gene Lehman
> To: fairchildclub@y...
> Date: Monday, November 05, 2001 5:51 PM
> Subject: Re: [fairchildclub] PT-19 tailwheel shimmy
>
> Hi Gene. Yep, I already have Russ's conversion. The trunion has
been
> machined and is a really snug fit. Everything is tight, pins,
bolts, etc.
> Except::: There's about 1/16th" play in the splines (mine is one
of those
> heavy-duty looking 6 spline gizmos). I'm guessing that's where the
shimmy
> starts, but I don't know. If that's the problem area, It's going to
be hard
> to fix. Maybe the guys with the two splines are better off. What
say ye
> Mr. Treat??
> Robert
>
>
> >Buy the Russ Harmuth tailwheel conversion. 800-304-7371 It will
help
> greatly and sometimes eliminates the shimmy. It is a long standing
problem
> with the Fairchild that we all fight. Check the attach pints in the
> fuselage as they tend to break with lost of shimming.
> >
> >For what it's worth.
> >
> >Gene
> >
> >
> >[Non-text portions of this message have been removed]
> >
> >
> >To unsubscribe from this group, send an email to:
> >fairchildclub-unsubscribe@y...
> >
> >
> >
> >Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
> >
> >
> >

'

robert hensarling · Post by **robert hensarling** » Tue Nov 06, 2001 12:20 pm

'-----Original Message-----
From: bt13a@earthlink.net
To: fairchildclub@yahoogroups.com
Date: Tuesday, November 06, 2001 12:12 PM
Subject: [fairchildclub] Re: PT-19 tailwheel shimmy

Hi Curt. I can't recall any play at all vertically. You have a good idea
there about the thick grease, I had considered filling the spline area with
clear silicone caulk (that would have been fun to clean up). Right now my
19 is still in Louise, Tx getting fitted with an electrical system
(starter, etc). I'll check more for vertical movement when I get it back.
You guys are right about the angle being close to vertical, seems like some
slant backwards would really help. Also, like someone else mentioned
earlier, these trainers probably weren't intended for use on asphalt.
I'm anxious to see you BT-13 fly next year!
Robert Hensarling
http://www.mesquiterocker.com
Uvalde, Texas

>You said the trunion has been machined and is tight...I assume you
>mean where it mates with the strut. The key is whether the trunnion
>has any vertical play between the fork and the strut flange. If so,
>try a thin washer made from plastic or brass.
>
>I'm not sure if the spline play will cause shimmy, but try using a
>bunch of very heavy grease to see if it helps. That would be a good
>indicator if it's the splines.
>
>I think the root of the Fairchild tailwheel shimmy problem is that the
>strut angle is too vertical.
>
>Curt Kinchen
>
>
>
>--- In fairchildclub@y..., "robert hensarling" wrote:
>>
>> -----Original Message-----
>> From: Gene Lehman
>> To: fairchildclub@y...
>> Date: Monday, November 05, 2001 5:51 PM
>> Subject: Re: [fairchildclub] PT-19 tailwheel shimmy
>>
>> Hi Gene. Yep, I already have Russ's conversion. The trunion has
>been
>> machined and is a really snug fit. Everything is tight, pins,
>bolts, etc.
>> Except::: There's about 1/16th" play in the splines (mine is one
>of those
>> heavy-duty looking 6 spline gizmos). I'm guessing that's where the
>shimmy
>> starts, but I don't know. If that's the problem area, It's going to
>be hard
>> to fix. Maybe the guys with the two splines are better off. What
>say ye
>> Mr. Treat??
>> Robert
>>
>>
>> >Buy the Russ Harmuth tailwheel conversion. 800-304-7371 It will
>help
>> greatly and sometimes eliminates the shimmy. It is a long standing
>problem
>> with the Fairchild that we all fight. Check the attach pints in the
>> fuselage as they tend to break with lost of shimming.
>> >
>> >For what it's worth.
>> >
>> >Gene
>> >
>> >
>> >[Non-text portions of this message have been removed]
>> >
>> >
>> >To unsubscribe from this group, send an email to:
>> >fairchildclub-unsubscribe@y...
>> >
>> >
>> >
>> >Your use of Yahoo! Groups is subject to
>http://docs.yahoo.com/info/terms/
>> >
>> >
>> >
>
>
>To unsubscribe from this group, send an email to:
>fairchildclub-unsubscribe@yahoogroups.com
>
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>

'