An aircraft including a ducted fan and an engine for driving the ducted fan includes a plurality of vanes movably mounted to the aircraft at a substantially rectangular exhaust end of the aircraft. Each of the plurality of vanes is substantially rectangular or square. The plurality of vanes are configured to alter an exit area of the exhaust end. The aircraft includes a sensor circuit for detecting a RPM of the engine and for outputting a RPM signal. The aircraft includes a control circuit coupled to the sensor circuit and the plurality of vanes. The control circuit is configured to actuate the plurality of vanes to alter the exit area of the exhaust end to vary a pressure load on the ducted fan to control the RPM of the engine in response to the RPM signal.