Most drives today either have springs, aerodynamic forcers (wings) or extract energy from the spindle motor to send the heads to the park position. Still, landing the heads on the platters is a lot harder on them that lifting the heads like in the "old days". I've seen plenty of drives where the heads were WELDED to the platters by old head lube that had either degraded over time or spread from the landing zone to the rest of the platter. Not sure if they are still using that landing zone lube or not. Anyway, all drives that are supposed to be parked can be assumed to handle it autonomously when power is removed, for nearly the last 20 years. Jon