The flying monkeys got me...

Helis and fixed wing

AMA 957918
IRCHA 4345
AMA Intro Pilot Instructor

Tuesday, March 22, 2016

Repaired SU-26 Horizontal Stab

The landing gear on these planes never comes off clean. When the get torn off, they roll, and in the case of wheel pants poke a hole in the underside of the wing as they go by. In the case of the pant-less Sukhoi, the gear itself crashed into the port horizontal stabilized and crushed the center. I didn't take a pic of the pretty bad damage, but this is a hollow stabilizer, no foam so it broke like an egg. I cut out the damaged section first...

I added the bar to the front of the stab, and the tabs to support the sheet balsa. You can see the clean wedge resection. This is the underside.

Not having a piece of wood that would create a clean single piece leading edge, and given the hollow design, I built up a leading edge over the bar I had installed, with scrap balsa straps cut to fit the gap and surround the bar. These would be sanded down and create a nice smooth leading edge. It is interesting how the original manufacturer curved the sheet balsa like a clams he'll to form the leading edge. Seems cumbersome.

I sheeted the stab with a custom cut piece of balsa that was a tad thicker than the stabs covering balsa, and let that dry overnight. I did this to both the bottom and top. They overshoot the leading edge and when sanded will segue sweet and clean into the leading edge supported by the wood bar I installed. I then sanded them flush with the adjacent leading edge and the stab sheet covering. The small gaps I filled with wood filler  (ran out of Hobbylite, and it would need very little). Allowed that to dry overnight, then sanded it flush. Perfectly smooth!

Bottom after cote applied. The orange is a tough match, I had none, and since it's not IMAC, I couldn't care less. It's neat, clean and orderly!

Record the top and leading edge of the stab. Done! Good as new!

Will need to test run the engine and make sure there is no fuel problem that lead to the engine cut out, and then I can take her out to the field in Merrimack and fly her off a decent runway. Psych!

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