Flap lower skin inboard cracks

[Gash]

My left flap lower skin is cracking at the aft inboard corner and also along the first line of inboard lower flap skin rivets. I guess I have a vibration issue, but I haven't felt anything in flight, and no abnormal control characteristics with flaps up or down. I have about 320 hours on my RV-8 now.

A search on VAF didn't find anything related on the topic (not saying it's not here somewhere...perhaps I'm using the wrong search terms). I'm wondering if I should repair the sheet metal with a patch or rebuild a new flap. I would love to avoid a full rebuild, of course.

Has anybody else had this cracking issue and what did you do about it? I would also like to find and solve the underlying cause to avoid future cracking after the repair.

I'll get some pictures when I get back to the hangar in a couple days.

[drill_and_buck]

Gash,
Sorry to hear about the crack. I have an 8 with just about 300 hours and do not have any cracks in this area. I did bend the most inboard portions of the flap upward to fit flush with the fuselage. I have not heard of any other occurrences of cracks in this area on the -8 or other RVs. Your speculation of the crack being vibration induced is exactly what I was thinking. Did you check with Vans on this?

Post a pic when you can.