stabilizer reinforcement

[6468]

A gentleman a few hangers down just bought a early serial number 140. I noticed he had no extra rivets along the top forward edge behind the main stabilizer spar. And when giving the sheet metal a squeeze (about an inch or so behind the main spar) there is some moderate deflection. I think he is missing the reinforcement channel. Is there another way to confirm it there? My plane has what looks to be an odd spaced rivet (1 3/8" spacing in the outboard rib leading up to the main spar) 2" back from the leading edge. Also, is it required (an AD)? There is only slight oil-canning when grabbing the end and pulling up-n-down gently. If it is missing ... is it required to be installed or just a good idea? I understand it can be lot of work to install, not trying to ruin his day, I want him to be safe but didn't want to say anything that is incorrect. I think I've talked him into joining our club, if for nothing else than to access the incredible source of technical information. He's a nu-bee with a lot of questions. Thoughts about the stabilizer reinforcement? Thanks

[mdtrn]

I'm looking for more information on this reinforcement. It was mentioned during a conversation I had recently, but I still am unclear, on what exactly is the issue, and how to tell if the work has been completed or not. Any one have pictures available?

[6597]

I'm not sure if you are confusing the leading edge reinforcement for the stabilizer or the elevator spar reinforcement AD, hope this helps.

Stabilizer leading edge reinforcement....

channel and leading edge.jpeg (98.23 KiB) Viewed 1931 times

Elevator spar reinforcement...

elevatorsparreinforcementAD.jpg (42.16 KiB) Viewed 1931 times

Fitting for elevator spar reinforcement AD...

elevatorreinforcement1.jpeg (68.18 KiB) Viewed 1931 times

[mdtrn]

Thanks for the pictures. Where would I find this "extra" or out of place" rivet I'm supposed to be looking for?