A fascinating exercise in complex aerodynamics, I think the lesson here for us is
care in control rigging and assembly.
For the purposes of WWI replica building and operation, directly from the AC 90-89A….
Quote:
i. What can be done about it?
Having described how flutter happens, the following suggestions
should help reduce the possibility of it happening
to the amateur-builder’s aircraft:
(1) Perform a mass balance of all flight
controls in accordance with the designer/kit manufacturer’s
instructions.
(2) Eliminate all control ‘‘free play’’ by
reducing slop in rod end bearings, hinges, and every
nut and bolt used in attaching flight controls.
(3) Ensure that all rigging and cable tension
is set accurately to the design specifications
using a calibrated cable tensiometer.
(4) Re-balance any flight control if it has
been repaired, repainted, or modified in any way.
NOTE: If the pilot experiences flutter, or
believes he did, reduce power immediately
and land as soon as possible. Do not attempt
further flight until the aircraft has been
thoroughly inspected for flutter induced
damage. This inspection should include all
wing/tail attach points, flight controls, their
attach points/hinges, hardware, control
rods, and control rod bearings for elongated
bolt/rivet holes, cracks, (especially rod end
bearings) and sheared rivets.
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