: Flight controls are balanced to prevent flutter (something that can
: kill you pretty fast). Any changes to the control surface require the
: surface to be removed and balance checked unless the manufactor has
: another method of compliance.

I am aware that they needed to stay balanced to prevent flutter... but I'd heard that just as an
overriding rule, moveable control surfaces are unrepairable.

I looked through my Cherokee service manual as an example. It doesn't specifically forbid control surface
repair, but it seems to imply that it's allowable... so long as it's within the balance limits. In fact, it says,

"Where possible the control surfaces were set with the balance weight on the heavy side of the limits, to
permit limited repair or paint touch-up without adjusting the balance weight."

and
"All replacement control surfaces, or surfaces that have been repainted or repaired, should be rebalanced
according to the procedures given in Paragraphs...blah,blah"

Seems that at least in the case of a Cherokee it's OK... provided they stay within balance limits.

-Cory

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************************************************** ***********************
* Cory Papenfuss, Ph.D., PPSEL-IA *
* Electrical Engineering *
* Virginia Polytechnic Institute and State University *
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