Streamline lift strut repair

[dlrude]

Hi all,

Has anyone seen, made, heard of a streamline wing strut splice using the inside sleeve method?

AC43.13-1B allows only outside sleeve repairs for lift struts.

But I am thinking that someone must have done and gotten approval for an inside sleeve splice especially perhaps a factory since its a nice way to use portions of tube that may be too short.

Any clues if such a thing has been done?

Thanks, Dave.

[skyking3286]

My first thought that is that you couldn't weld the ends to the strut since they are inside the strut and if you drilled holes
for rivets and bolts, you would weaken it. The only way to really weld in an inside is to do buttons and again, you are dealing
with drilled holes and nothing better than a butt joint in the strut.

[dlrude]

My first thought that is that you couldn't weld the ends to the strut since they are inside the strut and if you drilled holes
for rivets and bolts, you would weaken it. The only way to really weld in an inside is to do buttons and again, you are dealing
with drilled holes and nothing better than a butt joint in the strut.

Hi Mark,

Thanks for the response.

I don't follow it at all though.

What are "buttons"?

We do inside sleeve splices all the time on round tube. I am not sure why welding the ends would be any more or less difficult on a shaped tube. Can you elaborate?

Dave

p.s. I am referring to AC43.13;1B paragraph 4-95 when I refer to inside sleeve splices.

found here=> http://rgl.faa.gov/Regulatory_and_Guida ... r%2004.pdf

[Richard Murray]

David,

43-13-1B 4-101 pretty much says to repair streamlined tubing as shown in fig 4-43, which is the outside splice. It is my understanding thou shalt not deviate from 43-13.

Using the method of 4-95 how would you ascertain the diameter of streamlined tubing?

[Paul Agaliotis]

Dave,
I think Mark is refering to the rosette welds. In some of the older manuals they use an enlarged hole and weld the inner surfaces.
Paul

[dlrude]

David,

43-13-1B 4-101 pretty much says to repair streamlined tubing as shown in fig 4-43, which is the outside splice. It is my understanding thou shalt not deviate from 43-13.

Using the method of 4-95 how would you ascertain the diameter of streamlined tubing?

Hi Richard,

Use the method in figure 4-44 to make a sleeve of the proper inside fit.

AC43.13-1B is an advisory circular it is not mandatory, just available.

But recall my original question "Has anyone seen, made, heard of a streamline wing strut splice using the inside sleeve method?" I am looking for experiences where it has been done.

Here is a DER's response and it may better describe AC43.13-1B, look for Terry Bowden's response.

=> http://vb.taylorcraft.org/showthread.ph ... rut-repair

Thanks, Dave

[dlrude]

Dave,
I think Mark is refering to the rosette welds. In some of the older manuals they use an enlarged hole and weld the inner surfaces.
Paul

Thanks Paul, I got that part now.

Dave

[Paul Agaliotis]

Dave,
This once again an FAA enigma. Approved DATA is needed for major repairs, and Advisory Circulars are considered Approved DATA. But AC43.13 is by title is acceptable methods and practices, so is it approved? I don't know, but I try to avoid using it. It seems to scare the Feds. I prefer to use any factory information I can find and apply it to the repair I happen to be doing.
Check the CAM 18 it might have added information on this repair that was omited from AC43.13.
Paul

[skyking3286]

Mark is referring to the rosette welds...

Yes he was! I forgot the technical name for them for a second! At any rate, you
end of removing material and starting new paths for the stress to go through the strut
and it's no longer certified. The external splice is a bit like the spar splice... you have
enough material doubled that it takes care of the stress. Welds are often, but not always,
stronger than the original material (depending on the skill of the welder). But
removing material from a highly stressed part wouldn't give me much peace of mind
when things started to bump around on a summer day.

[Richard Murray]

Dave,

Thanks for the link to Bowden's comments.

I seem to recall seeing an inside splice years ago on a Taylorcraft, but I can't recall any details. Look in the structural repair manual for an L-2. I used to have a set of manuals and I will see if I can find it too.

[brink]

My first Champ 1128-E had a splice mid way in the area where the jury strut attached. This was in 1975, When you tapped the strut it sounded different about 14 inches of different tone. The rosettes they talk about were about 4 inches apart right in the center of the strut. My IA Verlyn Sickley at the time, looked at it, and found no 337 was ever posted on that repair. Both struts were pretty chipped up paint wise, so we removed them and stripped them, steel struts. The area of the weld was clean,I filed some roughness over the welds the right strut weighted about 20 ounces more than the left strut, Verlyn did a 337 field approval on a previous repair. And I was back in the air. 1128-E is still flying in a neighboring state,but has a new set of struts. I think Wag Aero might know how to get some repair material, my strut repair was cut at a 45 degree angle. Sickley thought the repair material used was probably off another damaged Aeronca strut. Great stuff, and Old School shade tree maintenance.