For detailed information see the IAC Calendar.
RC helicopters use a powerplant to turn a gear train, driving the main rotor system and tail rotors. They are capable of maneuvers that full-scale helicopter pilots only dream about. Each class has an established set of maneuvers that pilots must accomplish, and judges grade each maneuver. Class I includes primarily hovering-type maneuvers; Class II adds some forward flight, including a loop and stall turn; Class III adds even more aerobatic maneuvers and includes a power-off autorotation landing; and F3C adds a number of aerobatic maneuvers to test pilots and machines. The flight ends in a power-off autorotation landing that must be on a small spot for maximum points. (Not many miss it.) Helicopters also have a Scale competition.