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A first trailing edge portion of a scarfed jet engine exhaust nozzle aft of a second trailing edge portion relative to a central axis of an associated exhaust duct causes an automatic nozzle-pressure-ratio responsive transverse deflection of the associated exhaust flow away from the first trailing e

A first trailing edge portion of a scarfed jet engine exhaust nozzle aft of a second trailing edge portion relative to a central axis of an associated exhaust duct causes an automatic nozzle-pressure-ratio responsive transverse deflection of the associated exhaust flow away from the first trailing edge portion. When offset from both the center of gravity (CG) and the central longitudinal axis of an aircraft, at a relatively low nozzle pressure ratio, e.g. during takeoff, the thrust vector from the exhaust flow acts relatively close to the CG, whereas at a relatively high nozzle pressure ratio, e.g. during relatively high-speed cruise, the scarfed exhaust nozzle deflects the exhaust flow so that the resulting thrust vector is relatively parallel to the path of the aircraft. With the final portion of the exhaust duct skewed, the primary axis of the jet engine can be relatively parallel to the path of the aircraft.

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1. A jet engine exhaust nozzle, comprising: a. a relatively upstream duct portion adapted to receive a stream of exhaust gas generated by a jet engine, wherein a central axis of said relatively upstream duct portion is along a first direction;b. a bent duct portion downstream of said relatively upst

1. A jet engine exhaust nozzle, comprising: a. a relatively upstream duct portion adapted to receive a stream of exhaust gas generated by a jet engine, wherein a central axis of said relatively upstream duct portion is along a first direction;b. a bent duct portion downstream of said relatively upstream duct portion;c. a final duct portion downstream of said bent duct portion, wherein a central axis of said final duct portion is along a second direction, said second direction is oblique to said first direction, and said final duct portion is bent in a third direction relative to said relatively upstream duct portion by said bent duct portion; andd. an exit terminus of said final duct portion, wherein said exit terminus is scarfed so that a first trailing edge portion of said exit terminus on a first side of said final duct portion extends aftward of a second trailing edge portion of said exit terminus on a second side of said final duct portion, relative to said central axis of said final duct portion of said jet engine exhaust nozzle, said first and second sides are substantially opposite one another relative to said central axis of said final duct portion, and said first side of said final duct portion is in said third direction relative to said second side of said final duct portion, wherein in operation, said exhaust gas is discharged from said exit terminus in a fourth direction, said final duct portion in cooperation with said exit terminus provides for said fourth direction to be relatively aligned with said second direction when said jet engine exhaust nozzle is operated at a first nozzle pressure ratio, and said final duct portion in cooperation with said exit terminus provides for said fourth direction to be relatively oblique with respect to said second direction in a direction opposite to said third direction when said jet engine exhaust nozzle is operated at a second pressure ratio, said first nozzle pressure ratio is less than said second nozzle pressure ratio, and a direction of said fourth direction responsive to said nozzle pressure ratio of said jet engine exhaust nozzle is inherently passively responsive to an interaction of said stream of exhaust gas with said jet engine exhaust nozzle, independent of any moving parts. 2. A jet engine exhaust nozzle as recited in claim 1, wherein said exit terminus comprises a concave profile. 3. A jet engine exhaust nozzle as recited in claim 1, wherein said exit terminus is substantially planar and oblique to said central axis of said final duct portion of said jet engine exhaust nozzle. 4. A method of operating a jet engine incorporating the jet engine exhaust nozzle set forth in claim 1, comprising: a. directing a stream of exhaust gas in a first direction;b. deflecting said stream of exhaust gas so as to flow in a second direction, wherein said second direction is deflected in a third direction relative to said first direction; andc. ejecting said stream of exhaust gas in a fourth direction from said jet en sine exhaust nozzle operatively coupled to or a part of said jet engine, wherein said fourth direction is relatively aligned with said second direction when said jet engine is operated in accordance with a first operating condition, said fourth direction is relatively oblique with respect to said second direction in a direction opposite to said third direction when said jet engine is operated in accordance with a second operating condition, a nozzle pressure ratio of said jet engine exhaust nozzle at said first operating condition is less than said nozzle pressure ratio of said jet engine exhaust nozzle at said second operating condition, and a direction of said fourth direction responsive to said nozzle pressure ratio of said jet engine exhaust nozzle is inherently passively responsive to an interaction of said stream of exhaust gas with said jet engine exhaust nozzle, independent of any moving parts. 5. A jet engine exhaust nozzle, comprising: a. a relatively upstream duct portion adapted to receive a stream of exhaust gas generated by a jet engine, wherein a central axis of said relatively upstream duct portion is along a first direction;b. a bent duct portion downstream of said relatively upstream duct portion;c. a final duct portion downstream of said bent duct portion, wherein a central axis of said final duct portion is along a second direction, said second direction is oblique to said first direction, and said final duct portion is bent in a third direction relative to said relatively upstream duct portion by said bent duct portion; andd. an exit terminus of said final duct portion, wherein said exit terminus is scarfed so that a first trailing edge portion of said exit terminus on a first side of said final duct portion extends aftward of a second trailing edge portion of said exit terminus on a second side of said final duct portion, relative to said central axis of said final duct portion of said jet engine exhaust nozzle, said first and second sides are substantially opposite one another relative to said central axis of said final duct portion, and said first side of said final duct portion is in said third direction relative to said second side of said final duct portion, wherein said exit terminus comprises a convex profile. 6. A jet engine exhaust nozzle, comprising: a. a relatively upstream duct portion adapted to receive a stream of exhaust gas generated by a jet engine, wherein a central axis of said relatively upstream duct portion is along a first direction;b. a bent duct portion downstream of said relatively upstream duct portion;c. a final duct portion downstream of said bent duct portion, wherein a central axis of said final duct portion is along a second direction, said second direction is oblique to said first direction, and said final duct portion is bent in a third direction relative to said relatively upstream duct portion by said bent duct portion; andd. an exit terminus of said final duct portion, wherein said exit terminus is scarfed so that a first trailing edge portion of said exit terminus on a first side of said final duct portion extends aftward of a second trailing edge portion of said exit terminus on a second side of said final duct portion, relative to said central axis of said final duct portion of said jet engine exhaust nozzle, said first and second sides are substantially opposite one another relative to said central axis of said final duct portion, and said first side of said final duct portion is in said third direction relative to said second side of said final duct portion, wherein said exit terminus comprises an undercut profile.