Just wondering how often the Rotor Brake is actually applied. I recall in the mid nineties seeing a Jet Ranger parked on a platform helideck. A severe squall sprang up and in no time at all the rotor started turning, the aircraft began to bounce about on it's floats (it was the only one in our fleet which operated with floats) until it tipped over the side, demolished the safety netting and plunged into the sea.