Cracks found in Cockpit

[Kristofer Duckett]

Hi all,

I am in the middle of an annual with my mechanic, and we have found cracks in the cockpit. These cracks are located on the forward sides of the door and the opposite side (pilots side). There is a small hole, maybe inspection hole or a hole for the rivets that were drilled. Has anyone had any experience with this? Here is a picture where they are located along with the manual cut out of the location. The sections definately do not appear to be structural but wanted to see if any else has had this issue. thoughts?

[Kristofer Duckett]

Apologies, not the door the cracks are on a small piece of metal on the floor. This section has an oval shaped hole for either inspection or for rivets. The are located on both side and appear to have been there for quite some time. Again, they do not appear structural, and the manual as you can see does not even show them in the diagram. Thoughts?

Kris

[Kristofer Duckett]

Darnit I keep forgetting info, I have a 1963 PA-24 250.

[Kristofer Duckett]

OK here are some pictures of the cracks. If anyone has any thoughts or advice please feel free. Thanks!

[Hank Spellman]

Although this is a really hazy memory, I seem to recall that Maurice Taylor had an article in the Flyer regarding cracks about where you have yours. My memory is that it was limited to 260B models. At any rate, it did not seem to apply to my airplane, so I did not pay a lot of attention. My recollection is that the announcement was in a Flyer column called "From the Desk of Maurice Taylor."

Perhaps someone who has the old small size back issues can find it. Also, it might be in the tips special.

Good luck.

Hank
Henry A. Spellman

[Zach Grant L1011jock]

That is most probably residual damage from a gear up event as the frames involved would have deflected tearing the area in question, but when the skin/lower flange of the frame was replaced, it would return to its undeflected position. Just a guess, but I think most probable. I cant think of a good reason for movement in this area otherwise.
-Zach

[Ojars Balodis]

Hi Kristofer,
Greetings from Australia.
I imported a 1965 260 3 years ago from CA and discovered cracks eminating from this oval track shaped hole as well.
My aircraft had definately not had a gear up, so I would be discounting that theory.
My engineers here in Australia fabricated doubler plates to suit the area, removed rivets from the region and the
outer skin and inserted the new piece epoxied and re rivited.
I can recall reading an article in the Comanche tips book about this very issue and the fact that it happens
in nearly all the comanches with this oval track cut out at somewhere around the 3-4,000 hr mark.
I would bet there are hundreds of Comanches flying around with these cracks because normally you don't get to inspect this area
unless you remove the interior side panels and insulation.
Should be fixed as they are adjacent to the front attachment plate for the wings.
If you are interested I could look back and try to find the ICS tips and email you pictures of my cracks and repairs.
Regards,
Ojars Balodis

[Kristofer Duckett]

Thank you all for the responses.

Greetings Ojars!

I was able to locate the article in the TIPS section but it wasnt very thorough, If possible i would greatly appreciate the pictures from your repair. Thanks for the help!

Kris

[Ojars Balodis]

Hi Kristofer,
Have attached some photos before and after.
You may have to zoom in on the after shots as I had not specifically
taken any of the repairs.
The doubler was riveted and epoxied in place as well during the process.
I can recall about 3-4 rivets being replaced on the outer skin in a vertical plane
during the procedure.
Hope they are of assistance and we may meet up at Oshkosh in 2012
if you are going.
Regards,
Ojars