Auxiliary power and thrust unit

In an aircraft having a tail cone located aft of a vertical stabilizer, the improvement comprising an aircraft auxiliary power and thrust unit including:

• (a) a turbofan engine having an intake end, an exhaust end, and a main turbine shaft;
• the engine being located in the tail cone with the engine exhaust end arranged to expel engine exhaust out the rear of the tail cone;
• (b) a single air intake opening located on an upper surface of the tail cone at a body station location forward of the engine intake end and aft of the vertical stabilizer;
• an inlet door being hinged to the tail cone at the single air intake opening for selectively allowing and prohibiting air input, the inlet door opening in a forward direction;
• (c) an inlet duct extending between the air intake opening and the turbofan engine intake end;
• (d) a transmission assembly including a drive shaft mounted to the engine main turbine shaft and a gearbox connected to the drive shaft;
• the drive shaft extending axially from the main turbine shaft and forward through the inlet duct through a sealed opening in the inlet duct, the gearbox and drive shaft being located forward of the turbofan engine;
• and
• (e) auxiliary equipment located in the tail cone and connected to the gear box;
• wherein the unit includes a first operating mode in which the engine is operated at a low setting to power the auxiliary equipment and a second operating mode in which the turbofan engine is used to provide aircraft thrust and operate auxiliary equipment.