Pawnee landing gear

Each side of the landing gear of the Pawnee is fastened with 3 bolts. Each
fore and aft outboard bolts connect through 2 sets of tabs welded to the
lower fuselage longeron. Our right hand gear is slightly loose at the
forward attach point . Either the holes in the 2 tabs are worn out-of-round
or the bolt is worn (or both). Do not know the actual condition as the bolt
has not been pulled yet (cold in the north country).
Have any other Pawnee operators seen this problem? If so, what was the
problem and what was your method to fix.

Duane Eisenbeiss
eisenbeiss at compuserve dot com

wowway news wrote:
If so, what was the
problem and what was your method to fix.

The bushings in the landing gear attach points are probably worn.
Remove landing gear, inspect the bushings, and, the attach bolts, insert
new bushings, and, or, bolts, if found to be worn.

On Dec 5, 11:58*pm, "wowway news" wrote:
Each side of the landing gear of the Pawnee is fastened with 3 bolts. Each
fore and aft outboard bolts connect through 2 sets of tabs welded to the
lower fuselage longeron. *Our right hand gear is slightly loose at the
forward attach point . Either the holes in the 2 tabs are worn out-of-round
or the bolt is worn (or both). Do not know the actual condition as the bolt
has not been pulled yet (cold in the north country).
Have any other Pawnee operators seen this problem? * If so, what was the
problem and what was your method to fix.

Duane Eisenbeiss
eisenbeiss * at * compuserve * dot * *com

Open it up and inspect fully- no matter how cold. I have found the
mounting brackets broken. You really want to take a hard look at this.
We also change bolts at least once a year.
UH

Open it up and inspect fully- no matter how cold. I have found the
mounting brackets broken. You really want to take a hard look at this.
We also change bolts at least once a year.
UH

We plan to remove the bolt for a complete inspection. Just have not done so
since the late Nov annual inspt. This is a work in progress. I was just
wondering if others had seen similar problem. The gear attach points have
been inspected as well as can be done without removing the gear.

When you say that you have found the mounting brackets broken do you mean
the actual tab or the weld attaching the tab to the longeron?

Thanks for the reply Hank.

Eisenbeiss

On Sunday, December 6, 2009 at 2:06:24 PM UTC-5, wrote:

We also change bolts at least once a year.
UH

Is this just 'common sense' or is it recommended in a maintenance manual or AD?

I'm looking for information specifically about the failure of one of these bolts. I've scanned through the Piper PA-25 AD index and did not find an AD that mentions them. Are there known cases of these bolts failing and gear collapsing?

Maybe the information is out there and I just don't know how to find it. Sharing of your expertise is very much appreciated.

On Friday, August 21, 2015 at 9:12:52 PM UTC-4, son_of_flubber wrote:
On Sunday, December 6, 2009 at 2:06:24 PM UTC-5, wrote:

We also change bolts at least once a year.
UH

Is this just 'common sense' or is it recommended in a maintenance manual or AD?

I'm looking for information specifically about the failure of one of these bolts. I've scanned through the Piper PA-25 AD index and did not find an AD that mentions them. Are there known cases of these bolts failing and gear collapsing?

Maybe the information is out there and I just don't know how to find it. Sharing of your expertise is very much appreciated.

It's called, "After having bolts break as well as tabs, it's easier to replace bolts & look things over frequently.... rather than wait until it breaks (usually middle of a busy day....)".

I've helped a few times, Hank has been through it a lot more times.

Depends on number of landings, how hard were they & how smooth the field.

I am not aware of a specific document stating the shorter changes/"look overs".

On Friday, August 21, 2015 at 9:12:52 PM UTC-4, son_of_flubber wrote:
On Sunday, December 6, 2009 at 2:06:24 PM UTC-5, wrote:

We also change bolts at least once a year.
UH

Is this just 'common sense' or is it recommended in a maintenance manual or AD?

I'm looking for information specifically about the failure of one of these bolts. I've scanned through the Piper PA-25 AD index and did not find an AD that mentions them. Are there known cases of these bolts failing and gear collapsing?

Maybe the information is out there and I just don't know how to find it. Sharing of your expertise is very much appreciated.

It is a practical response to having had failures of the gear mounting brackets as well as bolts.
Ours is a 150 Pawnee converted to 180 so it has a somewhat lighter gear than the later 235. All the bolts on the 235 are one size larger.
Our field is rough and we do about 1000 landing a year with this airplane.
I am not aware of any AD nor any maintenance manual info on this.
UH

We have a -235 model. The integrity of the gear is checked each annual, but not taken apart. I think in the 15 years we have had the Pawnee, the bolts, bushings were replace once. The shock cords, I think every five years. We operate on a paved runway, not rough gravel or sod.

BillT

PA-25-235 bolt failure pictures
https://imgur.com/a/MgE77

Nice pictures but what we really need are clear closeups of the fracture surfaces and a clear description of the location of the origin of the fracture and the supporting structure, on the airframe and the undercarriage.
That might tell whether something more than just changing the bolts at some schedule prior to likely failure is sufficient.



On Saturday, December 5, 2009 at 9:58:43 PM UTC-7, wowway news wrote:
Each side of the landing gear of the Pawnee is fastened with 3 bolts. Each
fore and aft outboard bolts connect through 2 sets of tabs welded to the
lower fuselage longeron. Our right hand gear is slightly loose at the
forward attach point . Either the holes in the 2 tabs are worn out-of-round
or the bolt is worn (or both). Do not know the actual condition as the bolt
has not been pulled yet (cold in the north country).
Have any other Pawnee operators seen this problem? If so, what was the
problem and what was your method to fix.

Duane Eisenbeiss
eisenbeiss at compuserve dot com