I'm clearly going to have to do further studies! Any suggestions re further reading material?
As a training aid for students, I used a bicycle front wheel to illustrate the effects of gyroscopic precession. Held at arm's length it graphically demonstrated both gyroscopic inertia and precession.
But while we are talking about negative G, I have never worked out what went wrong with Hiller 12E that I was flying when I experienced a severe negative G event.
I watched in horror as a geologist's rock pick rose of the lap of the lass along side me, spun slowly in the air, headed towards me then attacked the windsreen instead. By then I was steeply nose down with dust coming up from the floor, and a severe overspeed on both rotor and engine.
I didn't even know about mast bumping in those days (80's), but there was no evidence of damage apart from that to my underwear.
Perhaps the event was intiated by a willi-willi (dust devil), but there had to be much more to it than that. I wondered if the blade sweep had been incorrectly set. Perhaps an LAME with more Hiller experience could suggest an answer.
CASA could throw no light on the matter, nor could any of the Bankstown engineers. I even wrote to Ray Prouty, and he was unable to provide any insights.
So to this day, I am none the wiser.
thekite