Autorotating a BO105 Helicopter 

I recently ferried a helicopter from San Francisco to Boston. Along the way, we watched this pilot practicing autorotations. An autorotation is when a pilot glides a helicopter without using the engine. In this case, the pilot is practicing, and uses the engine at the bottom of each one to terminate in a hover. In an actual engine failure, he would use the rotor inertia to land.
self