Flutter is no joke. There are many instances of this happening with improperly balanced/rigged elevators shearing the empennage off the aircraft (think V-tail Bonanza AD, but there are many other examples). The Rutan VariEZE canards were separating in flight after home builders were building them out of spec or too heavy.
Vibrational mechanics basically treats everything as oscillating mass spring systems (i.e. your airplane in flight is reduced to an abstraction as a mass bouncing up and down on a spring) and things like the natural frequency of oscillation are then mathematically derived. Flutter occurs when the surface pressure forces from the relative wind interact with the wing structure to excite oscillation at its natural frequency. At this point, each cycle feeds energy into the system and the oscillation gets bigger and bigger until something breaks.
Normally engineers figure out where this occurs and mark the Vne speed before that point. But all it takes is an unbalanced or out of spec elevator, or in this case improperly tensioned ailerons, and you can get flutter at much lower speeds because the natural frequency of the whole system is changed. This is why a lower Vne speed was part of the Bonanza AD.
Anyway, if that were me in that Hawker I would have needed a new pair of trousers. I can honestly say that flutter is one of the few topics that the more I learn about it in Aerospace Engineering, the less I wish I knew as a pilot!
