Abstract: Tail cone apparatus and methods for reducing nozzle surface temperatures of aircraft engines are disclosed. An example apparatus includes a tail cone to be coupled to an aircraft engine. The tail cone includes a central axis, a cone section, and a plurality of fins. The fins are spaced about the central axis and extend outwardly from an outer surface of the cone section.

Abstract: Tail cone apparatus and methods for reducing nozzle surface temperatures of aircraft engines are disclosed. An example apparatus includes a tail cone to be coupled to an aircraft engine. The tail cone includes a central axis, a cone section, and a plurality of fins. The fins are spaced about the central axis and extend outwardly from an outer surface of the cone section.

Abstract: A nozzle effective exit area control system is created with a convergent-divergent nozzle with a divergent portion of the nozzle having a wall at a predetermined angle of at least 12° from the freestream direction. Disturbance generators are located substantially symmetrically oppositely on the wall to induce flow separation from the wall with the predetermined wall angle inducing flow separation to extend upstream from each disturbance generator substantially to a throat of the nozzle pressurizing the wall and reducing the effective area of the jet flow at the nozzle exit.

Abstract: A thrust vectoring system is created with a convergent-divergent nozzle having a total angle no greater than 150 degrees. A divergent portion of the nozzle has a wall at a predetermined angle of at least 12° from the freestream direction. A disturbance generator is located on the wall to induce flow separation from the wall with the predetermined wall angle sufficient for the induced flow separation to extend upstream from disturbance generator substantially to a throat of the nozzle pressurizing the wall and creating a net vector angle in jet flow through the nozzle.

Abstract: Supersonic projectile nose cones with flat tips are disclosed. An example apparatus includes a nose cone for a projectile configured for supersonic flight at velocities of at least Mach 2.0. The nose cone has an axisymmetric body extending from a base to a tip. The body has a thickness and defines an interior cavity. The tip is defined by a flat face normal to a central axis of the projectile.

Abstract: A nozzle effective exit area control system is created with a convergent—divergent nozzle with a divergent portion of the nozzle having a wall at a predetermined angle of at least 12° from the freestream direction. Disturbance generators are located substantially symmetrically oppositely on the wall to induce flow separation from the wall with the predetermined wall angle inducing flow separation to extend upstream from each disturbance generator substantially to a throat of the nozzle pressurizing the wall and reducing the effective area of the jet flow at the nozzle exit.

Abstract: A thrust vectoring system is created with a convergent-divergent nozzle having a total angle no greater than 150 degrees. A divergent portion of the nozzle has a wall at a predetermined angle of at least 12° from the freestream direction. A disturbance generator is located on the wall to induce flow separation from the wall with the predetermined wall angle sufficient for the induced flow separation to extend upstream from disturbance generator substantially to a throat of the nozzle pressurizing the wall and creating a net vector angle in jet flow through the nozzle.

Abstract: A nozzle effective exit area control system is created with a convergent-divergent nozzle with a divergent portion of the nozzle having a wall at a predetermined angle of at least 12° from the freestream direction. Disturbance generators are located substantially symmetrically oppositely on the wall to induce flow separation from the wall with the predetermined wall angle inducing flow separation to extend upstream from each disturbance generator substantially to a throat of the nozzle pressurizing the wall and reducing the effective area of the jet flow at the nozzle exit.