This is from a friend of mine who had it demonstrated in the OH-58 (Bell 206) in the army:
“At VNE, the nose will gradually try to climb, and when you push the cyclic forward more to maintain level flight, it will continue to do so. Just before the max forward cyclic, the fuselage panels begin to oil-can, at which point the nose will come up and force the machine into a vertical climb, before breaking sharply, similar to a hammerhead stall.”
Will see if I can find more
phil