Patent ID: 6688552
Filing Date: 2004-02-10
Classification: F02C,F02K,Y02T

Abstract:
A variable cycle of propulsion system for a supersonic airplane, the propulsion system comprising:at least one low-bypass ratio engine capable of generating thrust for supersonic flight speeds; at least one high-bypass ratio auxiliary propulsion assembly separate from the at least one low-bypass ratio engine, the at least one high-bypass ratio auxiliary propulsion assembly being capable of generating additional horizontal thrust for takeoff, landing, and subsonic cruising flight at subsonic flight speeds of the airplane, the at least one high-bypass ratio auxiliary propulsion assembly including at least one fan and not having a gas generator; a mechanical transmission system configured to transmit rotation from a shaft of the at least one low-bypass ratio engine to the at least one fan to enable the at least one high-bypass ratio auxiliary propulsion assembly to generate additional horizontal thrust for the takeoff, the landing, and the subsonic cruising flight at the subsonic flight speeds of the airplane, and to reduce noise during the takeoff, the landing, and the subsonic cruising flight by increasing the bypass ratio of the propulsion system; and decoupling means for decoupling the mechanical transmission system to enable supersonic cruising flight at the supersonic flight speeds of the airplane, the at least one fan of the at least one high-bypass ratio auxiliary propulsion assembly being integrated in the airplane fuselage of the airplane to reduce drag during the supersonic cruising flight at the supersonic flight speeds of the airplane.