 The United States Air Force (USAF) regularly uses H-70, a 70% hydrazine 30% water mixture, in operations employing the General Dynamics F-16 “Fighting Falcon” fighter aircraft and the Lockheed U-2 “Dragon Lady” reconnaissance aircraft.The single jet engine F-16 utilizes hydrazine to power its Emergency Power Unit (EPU), which provides emergency electrical and hydraulic power in the event of an engine flame out.The EPU activates automatically, or manually by pilot control, in the event of loss of hydraulic pressure or electrical power in order to provide emergency flight controls.