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"stock" S1S wing strength?

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Active Member
Mar 14, 2008
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Hi Guys,

I've got a question I hope you all can answer. I am getting pretty serious about buying another S1S (Actually I have things narrowed down to 3 completely different airplanes)

Anyway I'd like to know what your opinions are about the strength and durability of bone stock S1S wings.
This particular Pitts is made from factory kits if that makes a difference. Empty weight 809 lbs.

I found my front top wing spars cracked inboard of the I struts on my old S1S. I also had some broken nose ribs, I think on the bottom wings, but it has been a long time ago now, and I can't remember for sure. I didn't feel qualified to build new wings and ended up selling it as salvage 9 years ago. I was flying shows in it and flew it quite hard. Average show was +7-4 "G" (practices a little less)with lots of gyroscopics. I never exceeded the placarded entry speeds, but if max snap speed was 140 I was snapping right at 140, 5 turns on a 45 downline. I also was flying some pretty long tailslides.

My S1S was a homebuilt and the spars would have been legal in a certified airplane as to slope and grain spacing, but just barely.

Anyway it has taken me years to save up enough money to buy another acro mount and I don't want to have the same problems again. Nor to I want to get killed, as I practiced for bail outs, but honestly don't think the chances of gettng out are great.

Soooo..... Do you think I am asking for the same kind of problems with a bone stock S1S wing, or should I be ok?




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