Jonathan,
Well done for 'coming out' over an overspeed occurrence - we have all done it to
a larger or lesser extent and the questions you pose are very relevant.
I am not speaking for Europa Aircraft (current or past) or for the Club,
however,
generally, the flap limiting speed is determined having conducted a stress
analysis of the whole system. The failure mode that causes the first failure
or lowest reserve factor (RF) is associated with a speed within the V-N
envelope.
A suitable factor is applied (which in any case will include at least 1.5
for LIMIT to ULTIMATE and, most likely, additional factors such as 1.15 fitting
factor (at joints) or even 1.33 (for regularly dismantled items). For composite
structure failures, there are yet more factors that take into account the
environmental influences (e.g. temperature, humidity) and variability of build
standard.
Regarding loads, as air pressure is proportional to the square of the airspeed
the loads can rise very quickly. For your overspeed occurrence, the flaps would
have seen a dynamic pressure of approx 1.45 (i.e. 100^2/83^2 = 1.45, hence
45% overload). By definition this is somewhere between LIMIT and ULTIMATE load
levels, hence some detrimental deformation may have occurred.
The tg Owners Manual states "Vfe Maximum flap extended speed is the highest
speed
permissible with the flaps in the prescribed extended position".
PoH states Vfe as 83kts. Vfe (max speed for extending/retracting flaps) implies
the actuator is the weak link. Vf would be a flap limiting speed.
You have done exactly the right thing, you have inspected the system for
deformation.
It is likely that no damage has occurred at all.
If damage has occurred, the Europa actuator end attachment holes may have
ovalised
very slightly (rattle tested?) but I suspect the flap end-pin and bearing
(and the attachment into the flap) are
over-engineered and will be unaffected.
Maybe you could add an additional disassembly/inspection to the flap actuator
end
fittings when the aircraft is under it's next scheduled maintenance.
I suspect Bud may also have some useful input!
Regards
John
--------
John Wighton
Europa XS trigear G-IPOD
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