This is a 10-inch diameter tube. How far from an open and accessible end of
the tube is the damage located? It may not be possible to reach the patch
on the inside of the tube to properly buck the rivets...

The photo and description indicate the damage is across the tube. 4.1-inches
is a quite a chunk of the total circumference (13%) to removed and then
attempt to bridge with a riveted patch. The cited sections of AC43.13 may
not be appropriate repair guidelines for this particular tube structure.

If the builder's handbook does not provide repair guidelines for this tube,
you should probably hire a qualified aircraft structural engineer to develop
a suitable repair technique that the experimental/homebuilt inspector (FAA)
will accept.


wrote in message
...
On Jul 13, 5:21 pm, "RPM the A&P" wrote:


The damaged area is on a 10in diameter .065in 6061 T6 tube that serves as
the tail boom on this aircraft. The part was dropped and sustained a
crease
roughly perpendicular (but not quite) to the length of the tube.

I have removed the displaced material and now have an opening 4.1in long
and
1.1in wide.
--------------------------------------------------------------------------------

I'd go with the patch. But I'd like to know more about that portion
of the structure, especially with regard to the condition of the
surrounding area. Depending on what's already there and the condition
of the tube, I'd probably try to distribute the load a little better
-- might come out looking more like a sleeve.
-R.S.Hoover
PS - John got it right. Seems kinda casual to risk your life on a
snap-shot... for all we know there could be a bullet hole on the other
side :-)