Thank you Lopflyers. I really have mixed emotions about this one and the reason is you said the onset occurred just after a power reduction in a climb. Now its almost impossible to characterize when flutter will start to occur but more often than not it seems to happen with our models at median to high speed perhaps with some load being applied and at high throttle settings. That cannot rule out aerodynamic flutter in you case however.

Now if we can rule out some sort of weird vibration induced problem going on with any of the electronics and the only way I can think of duplicating that on the ground is with a thourghly anchored airplane and a high power static run up.

If that proves clean, to be honest I would if it were my airplane be mass balancing the ailerons immediately before any further flights.
mass balance contrary to popular mis conception does not need to completely balance the full weight of the surface (in this case the aileron) not anywhere near it and only a tiny portion of the weight will do.

There are many ways to secure a small fishing weight attached to the aileron forward of the hingeline If you are interested then we can explore.

I am not any kind of expert only a survivor

G'Day Mike, Concerning the torque structure on the elevator halfs of you friends new ship. I'd bet a burned out glow plug aginst a stale Gazzed Donut that that damage was precipitated by just one of two things, either hanger rash in other words banging a elevator into a a door jam or a tailgate and hear that small crack sound but just saying or hopping it will be alright - Or -the evil F word flutter that is.

Flutter can be an insidious thing and not all surface flutter is auditable. One day a local fellow landed his new 40 sized three D ship and found an aileron servo stripped. Yup a cheap one he thought and bought a more expensive one. Low and behold this one soon did this agine. I suggested flutter and mass balance, nope more better servo yet agine, This time since it was metal gears all the servo screws came out instead This went even another cycle with predictable results and fortunately the dangling servo did not cause a crash. At that time he used one of my simple little balance widgets and there was never a recurance agine.

John