On 2006-03-22, Robert M. Gary wrote:
http://www.thegaryhouse.com/aircraftdamage/

I was down in a remote area of Mexico this last weekend and a truck
backed into my aileron.

One thing to watch out for on seemingly minor damage near the outboard
edges of wings is a bent spar. Think of how much torque on the inboard
part of the wing that an impact to even make a small dent would make.
Needless to say, kinked spars are vastly weaker than unkinked spars.

Our club had a Cessna 170 - someone put the wingtip into a hangar at
taxi speed making a small dent in it. It also made a small kink in the
aft spar even though it was at low speed and seemingly only cosmetic
damage - the spar had to be repaired before the aircraft was airworthy
again.

I believe Highflyer has a story about hitting a wingtip of a Taylorcraft
on a pole at taxi speed - the damage appeared merely cosmetic but
the aft spar fractured in flight, which could have quite easily been fatal.
The torque from hitting the wingtip on the pole caused a compression
fracture in the wooden spar.

--
Dylan Smith, Port St Mary, Isle of Man
Flying: http://www.dylansmith.net
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