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review
I
concur that when it happen to you I definitely can really ruin a perfect day.
I
experienced it first hand in my Zenith CH300 last fall on the way back from a
flight from Hanover to Brampton Ontario. Coming down to get into the Toronto
control zone. Speed was increasing to 145 mph. At the time I thought
the engine wanted to leave the aircraft. It stopped after throttling
back.
Quite
an experience. After landing we checked around the plane. The engine seems
ok, then the wings, ailerons and the tail, still no luck. The next day, took the
plane in the circuit and started experiencing it again when turning crosswind at
80 mph. Oh shit again, ok throttle back then went around the circuit at 70
mph and landed.
After
further investigation, had someone holding the stick and went around moving the
ailerons we found that the source was a tie rod end bearing with some wear.
The nut holding it in place was still fully secured but not torqued enough
allowing the inner bearing to rotate on the rod itself. All the other components
were checked, control cable tension was as per specs.
Found
a new rod end bearing and replaced it and made sure it was torqued with no
chance to rotate anymore. Got it fired up and went to test fly it. No more
problems. Recently had the plane at 160 mph with no indications of any more
symptoms.
A
lesson learned is to go with a really fine tooted comb over your control system
for any signs of wear or looseness. It is not evident when doing the standard
preliminary flight inspection or annual.
Lets
be safe.
Alain
One of the A-7Ds in my squadron had an aileron
flutter problem - found a bearing for the aileron was loose in its mounting to
the wing (was "unstaked", not secured properly). When climbing at 400
KIAS passing between 15,000 and 17,000, the mach number was coming up to about
.80 and the flutter would self-excite with no manuevering - no damage, just
scared the pilot (yanked throttle to idle and pulled up to slow down and
it would stop, then returned to land declaring an emergency - thought it was
an engine vibration such as would be caused by losing a turbine blade in aft
end of engine. Engine was checked OK - flutter (never saw what was
fluttering, just felt an awful shaking of everything in the cockpit) was
repeatable on 3 different test flights. As this was a speed-altitude
condition no one ever flew at we kept flying the plane on regular
missions. Took several months before Vought led us to the cause -
the loose aileron bearing.
David
----- Original Message -----
Sent: Saturday, March 11, 2006 4:17
PM
Subject: [FlyRotary] flutter
encounter....AOPA article
>NEVER
AGAIN ONLINE: FLUTTERING WITH DISASTER Flutter and wing oscillations
rendered the aircraft uncontrollable with imminent structural failure as a
probable ending: a harrowing event with a remarkable outcome. The pilot's
swift action and a good dose of luck helped him and his passengers survive
the ordeal. Read ( http://www.aopa.org/epilot/redir.cfm?adid=8497
) how this pilot handled an extreme emergency--a lesson he would not wish to
repeat.<
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