Abstract: A thrust vectoring exhaust nozzle (10) includes a plurality of flaps (16-22) and seals (24-28) positioned by a unison ring (52) and flap links (54-60).

Abstract: A two dimensional exhaust nozzle for a gas turbine engine having reverse thrust capability includes a pair of spaced apart converging flaps which are able to rotate about their respective axes until their downstream edges meet along the engine centerline to block the flow of gases through the engine and to redirect the flow through fixed area reverser outlet ports. The axes about which each convergent flap rotates are spaced inwardly from their respective convergent flap surfaces. The flaps themselves cover the outlet ports when the flaps are in forward thrust operating positions. The flaps move away from and unblock the outlets as they rotate to their reverse thrust position. The distance between the flap axis and its convergent surface is critical to being able to use short flaps while obtaining large reverser outlet areas.

Abstract: An unstable ring resonator capable of providing an output beam having high power and high optical quality is disclosed. The unstable ring resonator is formed with a first region capable of providing transverse mode discrimination, beam magnification and improved beam quality, a second region capable of accommodating a gain medium and means for out coupling a beam of electromagnetic radiation to provide an output beam. Transverse mode discrimination is provided by the lowest loss mode characteristic of unstable resonators, improved mode discrimination and optical quality is obtained by utilizing mirrors having curved surfaces to focus the circulating electromagnetic radiation through spatial filters having line apertures and beam magnification is provided by the relative spacing of the curved surfaces.

Abstract: A laser aerodynamic window with different inside and outside gas stream components having effective stagnation indices of refraction corresponding to the indices of refraction of the gases on the opposite sides of the aerodynamic window so that the turbulent shear zones formed therewith respectively have substantially uniform stagnation indices of refraction for substantially eliminating unsteady laser beam distortion.

Abstract: A radial flow laser having an unstable resonator configuration with a standing wave optical path is disclosed. The gain medium forms a cylindrical sheath which is symmetric about a centerline axis through the resonator and the output beam is annular in cross section. The resonator geometry is based on a circular end mirror, an annular end mirror, an annular folding mirror having a reflective surface conforming to the inside of a cone geometry and conical folding mirror conforming to the outside of a cone geometry. Various embodiments are disclosed whereby the width of the resonant mode is either held constant or expanded to accommodate various power density loadings on the mirrors. In one configuration, the standing wave travels in a complete loop through the cylindrical sheath of gain medium.

Abstract: A radial flow ring laser having an unstable resonator configuration with a traveling wave optical path is disclosed. The gain medium forms a cylindrical sheath which is symmetric about a centerline axis through the resonator and the output beam is circular in cross section. The resonator geometry is based on first and second conical mirrors which are positioned symmetrically on the axis centerline and first and second annular mirrors which are symmetric about the axis and complete the ring path. The resonator description also includes an annular stripper mirror to produce the output beam of radiation and a suppression mirror to prevent a traveling wave in the undesired direction through the ring. An alternate embodiment includes a cylindrical folding mirror to cause the optical path to cross the centerline axis after each pass through the gain medium.