Abstract: This jet engine comprises of a complete low bypass turbofan unit 1 including secondary fan unit 2 and engine core, ahead of which sits a larger diameter main fan unit 3 driven from the front of the secondary fan via a long drive shaft 4. A center portion of the main fan would feed the secondary fan via long central duct 5. The outer portion of the main fan would be ducted into a split exhaust plenum chamber 6. This chamber has thrust vectoring exhaust mechanisms 7 immediately attached to each side, and then each side then feeds a thrust splitter 10, and then feeds to variable area outer ducting 8, using double-hinged inner and outer doors 9. Both outer ducts would rejoin the central duct downstream in a second plenum chamber 11 just ahead of the secondary fan. Between this chamber and secondary fan would be an intercooler 12.

Abstract: This Jet engine comprises of a complete low bypass turbofan unit 1 including secondary fan unit 2 and engine core, some five to eight feet ahead of which sits a larger diameter main fan unit 3 driven from the secondary fan via drive shaft 4. Between the main and secondary fans sits a reversed variable area nozzle 5 connected to the forward end of the secondary fan by a short inlet tube 6 (fitted with intercooler 12). At the back of the core sits another variable area nozzle 7 facing rearwards. This arrangement (front nozzle, inlet tube, secondary fan, core, rear nozzle) is enclosed by a variable diameter cylinder 8, providing a variable area bypass duct 9 between cylinder and engine outer casing 10 that extends backwards from the outer diameter of the main fan. A third variable area nozzle 11 is positioned aft of the outer casing facing rearwards.