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The craziness continues!

My continuing flirtation with Aviation:
I've purchased a 90% complete Mitchell U-2 Flying Wing!
(Which in Aviation math usually means, 90% is left to be done.)

Outer Wing Section Issues and Repairs

When we picked up either of the outer wing sections we could hear things rattling around inside of them - remnants of our past un-wanted rodent boarders.  After completing the work on the landing gear and its attachment we have decided that the plane might be salvageable.  So we decided to strip the fabric off the rest of the wing in order to clean up after the Oklahoma pests which will mean committing to the expense of replacing all the fabric and paint.

Good idea but we were in for a couple of real surprises!  1). The control cable tubing had become extremely brittle, broken and in need of replacement.  2). The inside of the wing was covered with rodent nesting material, urine and feces.  3). And finally the surface of the D-tube contained a bad span-wise "wave" which the original builder had tried to fill and finish using a combination of dry wall compound and Bondo.  Thank goodness we had decided to strip the fabric and found this mess so it could be repaired properly.

Here is most of the rodent "mess" we found as we started to strip the fabric.  Note the blotchy excess fabric cement and the broken control cable tubing.  Dry wall compound may have been used to shape the wingtip as well.

The wingtip solution turned into a fun project to make new wingtip fairings and that project is discussed on the Wingtip Fairings Page.

A better image of the control cable tubing failure at the other wingtip - our solution for replacing the tubing turned into a major project involving the addition of new pulleys.  

That project is discussed on the Cable Routing Page.

While removing the cream-colored fabric we notice chunks of filler material coming off of the D-tube.  It appears the original builder attempted to find a "quick" repair of a span-wise low spot located just in front of the spar by filling with Dry wall compound and then covering it all with Bondo - it failed!!!
After removing the fabric and vacuuming the entire wing section we still had a mess to wash-away from the ribs.
Post washing
Norm: busy, carefully removing the un-acceptable filling from the "wave" in front of the spar.  He couldn't just blast it with the sander because of the thinness of the D-tube so he had to be careful not to sand away any of the D-tube plywood.
After removing all the bad filling materials we roughly scribed and stacked two layers of aircraft grade plywood, epoxied them and cured them in the wave under a vacuum bag.  You can see the "wave" was approximately 40 in. long.
Next we carefully sculpted the plywood filler to the original profile as best we could.
And finally, we layered "Micro" over the plywood filler in a thin coat which will be sanded to a final finish.