Abstract: An outlet device for a jet engine comprises a number of fixed ducts, each with a gas intake and a gas outlet for conducting a gas from the jet engine, at least two of the outlets of said gas ducts open in different directions, and a gas distribution arrangement is arranged at the gas intakes for selective distribution of the gas to the ducts.

Abstract: Disclosed is a thrust termination device for a solid rocket motor, which terminates the net thrust by the reverse thrust of the rocket motor produced from the emission of the combustion gas in the reverse direction, when the stage separation signal is transferred at the normal thrust state of the rocket motor. An object of the present invention is to provide a thrust termination device for a rocket motor, which can contrive to accomplish the structural safety and mechanical sealing performance at the combustion chamber condition of the high temperature and high pressure, and easily remove the thrust termination device even at the low pressure state and open the trust termination ports successively with very small impacts when the thrust termination is commanded.

Abstract: A propulsion system may include a cylindrical support member and a tubular rotatable member rotatably mounted within the support member that may be adapted to permit fluid flow therethrough. The tubular rotatable member may extend past a down stream end of the support member. An exemplary embodiment of a propulsion system may also disclose a vane attached on an interior surface of the tubular member and may include a blade which extends in a direction toward a rotational axis of the rotatable member such that rotation of the tubular member and the vane attached thereon draws fluid into the tubular member to accelerate the fluid flow through the tubular member. Additionally, a nozzle may be attached to the down stream end of the support member and include a primary nozzle and a secondary nozzle within the primary nozzle. The secondary nozzle may be engaged with the primary nozzle by a stator.

Abstract: A fluidic diverter valve includes valve element freely disposed within a valve bore. The valve bore has a cross sectional area that varies. As a result, the clearance between the valve element and an inner surface of the valve bore also varies. This variation in cross sectional area, and thus clearance, is such that a force of sufficient magnitude to move the valve element from a seated position is initially applied to the valve element, but the force on the valve element is reduced once it is moved from the seated position. Thus, the impact force upon attaining another seated position is reduced.

Abstract: A propellant supply device (10) is provided for a vehicle (11) having a main propulsion motor (12) and having an attitude control system (11) including a plurality of thrusters (14A, 14B, 14C, . . . , 14F). The improved device comprises: a pressure vessel (15); first and second movable walls (20, 21) operatively arranged within the pressure vessel and dividing the interior space therewithin into three separate sealed chambers (22, 23, 24) from each of which fluid may be supplied; a first fluid (e.g., a first bipropellant) in one of the chambers; a second fluid (e.g., a second bipropellant) in a second of the chambers; and a third fluid (e.g., ammonia) in a third of the chambers, the third fluid being a volatile liquid having a liquid phase and a gaseous phase, and wherein all three chambers are pressurized to the vapor pressure of the third fluid.

Abstract: This patent concerns VTOL propulsion systems that develop a forward flow of air through the air intake duct(s), by the methods of a internal duct system, reversing the rotation of the fan, or a variable pitch (thrust reversing) fan.

Abstract: The present invention relates to a variable cycle boost propulsor system for use on an aircraft. The variable cycle boost propulsor system includes an engine, a turbine, a fan connected to the turbine, and a valve system for delivering the fluid output from the engine to the turbine for driving the turbine and the fan and thereby generating additional thrust for the aircraft. The engine is also used to provide power to one or more systems onboard the aircraft.

Abstract: An apparatus for providing propulsive power that utilizes a novel swirl generator for rapidly and efficiently atomizing, vaporizing, as necessary, and mixing a fuel into an oxidant. The swirl generator converts an oxidant flow into a turbulent, three-dimensional flowfield into which the fuel is introduced. The swirl generator effects a toroidal outer recirculation zone and a central recirculation zone, which is positioned within the outer recirculation zone. These recirculation zones are configured in a backward-flowing manner that carries heat and combustion byproducts upstream where they are employed to continuously ignite a combustible fuel/oxidizer mixture in adjacent shear layers. The swirl generator is compatible with the throttle range of conventional gas turbine engines, provides smooth combustion with no instabilities and minimum total pressure losses, enables significant reductions the in L/D ratio of the combustor and is readily packaged into various applications.

Abstract: A side thruster valve of an aerospace craft is improved to reduce torque of a servo-motor, etc. needed for nozzle opening and closing to thereby realize a compact and light weight device. The side thruster valve comprises a valve plug having its back directed to an axis of the aerospace craft and independently movable between a fully opened position and a fully closed position of the valve plug in a plane orthogonal to the axis of the aerospace craft, an actuating means for moving the valve plug in an axial direction of the valve plug and an elastic member for activating the valve plug in the axial direction of the valve plug. In a side thruster device comprising a plurality of the side thruster valves, the side thruster valves are arranged independently of each other to thereby broaden freedom of combustion control and improve fuel consumption.

Abstract: A rocket motor is disclosed that is suitable for use with an ejection seat. The rocket motor includes a combustion chamber, and has a plurality of spaced apart outlets arranged in fluid communication with the combustion chamber, to allow the passage of exhaust gases upon ignition of a propellant within the combustion chamber. Each exhaust outlet is arranged to direct the exhaust gases along respective fixed lines of thrust. The arrangement is such that the resultant thrust generated by the rocket motor acts along the line non-parallel with at least one of the fixed lines of thrust so as to direct the rocket motor along the curved trajectory. The secondary outlets may be smaller than the primary outlets and are selectively closable by valves.

Abstract: A side thruster of a flying object of the invention is provided with a solid gas generating agent, a nozzle arranged in a direction perpendicular to an axis of the flying object, a tube body for flowing the gas generated in accordance with a combustion of the solid gas generating agent to the nozzle, the solid gas generating agent being arranged around the tube body, a plurality of orifices provided on a peripheral wall of the tube body along its circumferential direction and capable of injecting the gas generated in accordance with the combustion of the solid gas generating agent toward an axis of the tube body, and a valve provided within the tube body and rotatable around the axis of the tube body so as to open and close the plurality of orifices.

Abstract: This propulsion system of a rocket motor assembly includes an array of attitude-control rocket engines, one or more oxidizer-fluid sources, one or more ignition-fluid sources, and, optionally, one or more primary rocket engines. Each of the attitude-control rocket engines has a respective combustion chamber and is offset from the longitudinal axis of the rocket motor assembly so that when a selected one or group of the attitude-control rocket engines is fired, the flight path of the assembly is diverted and/or the rocket assembly spins. The oxidizer-fluid and ignition-fluid sources are in operative communication with the attitude-control rocket engines to respectively permit oxidizer fluid and ignition fluid to be supplied to selected ones or groups of the attitude-control rocket engines. Optionally, a portion of the ignition fluid from the ignition-fluid source can be cooled and used to pressurize the oxidizer-fluid source.

Abstract: An exhaust nozzle for an aircraft engine. The nozzle includes a mount for attaching the exhaust nozzle to a downstream end of the engine and first and second opposed upstream flaps moveably connected to the mount having inner surfaces defining an upstream exhaust gas flowpath. Each upstream flap extends between an upstream end and a downstream end and is moveable relative to the mount between an open position in which the downstream ends of the upstream flaps are spaced by a first distance, and a closed position in which the downstream ends touch to substantially block flow through the exhaust gas flowpath. First and second opposed downstream flaps are moveably connected to the first and second upstream flaps having inner surfaces defining a downstream exhaust gas flowpath.

Abstract: A lateral-thrust control device for a four-quadrant final-phase guidance control of a missile having lateral-thrust nozzles (10) communicating with a solid-fuel gas generator (13). Each of the nozzles has a valve member (22, 38), whose open and closed states are controlled by a common actuator (12, 30) which is rotatable and axially displaceable to select one nozzle to be supplied with gas from the gas generator while the other nozzles are closed according to the required flight mode. The actuator is configured such that each of the lateral-thrust nozzles (20) can be individually controlled to be active or inactive, intermittently, and independently of one another. In one embodiment, the actuator is a cylindrical piston and in another is a conical member.

Abstract: A valve is disclosed for regulating the flow of a pressurized working fluid through a nozzle having a nozzle throat. In a preferred embodiment of the invention, the valve comprises a valve body defining a valve bore, a pressure inlet and a nozzle plenum. The nozzle plenum fluidly communicates with the nozzle throat. A valve seat is disposed between the pressure inlet and the nozzle plenum. A valve member is slidably disposed within the valve bore. The valve member comprises a first end disposed proximal the valve seat and a second end distal the valve seat. The first end comprises a valve face and the second end comprises first and second rear surfaces. The second rear surface is spaced apart from the first rear surface. The first rear surface cooperates with the valve bore to define a rear chamber. The second rear surface cooperates with the valve bore to define an actuation chamber, the volume of which is not a function of the valve member diameter.

Abstract: A synthesized divert propulsion system adapted to be utilized in various vehicles, including kill vehicles, interceptors, rockets, missiles and the like. The system is fabricated using microelectromechanical system (MEMS) technology which eliminates complex interconnections required for traditional divert propulsion systems by integrating all propulsion fluid functions and all controlled electronic functions onto a plurality of wafers. The wafers are integrated into a complete synthesized divert propulsion system by stacking and bonding the wafers together.

Abstract: A flow diverting mechanism for the twin duct offtakes or coannular offtake for a turbo fan engine powering aircraft with either thrust reversing or short takeoff and vertical landing or both capabilities includes a rotary drum mounted between the turbine and afterburner sections and includes ports complementing the inlets in the offtakes to divert the core stream through the offtakes and passages to proportion the fan discharge air utilized for cooling purposes in the engine to cool the liner and walls of the offtakes and the engine components located downstream of the rotary drum while assuring separation of the core stream flow and fan air flow.

Abstract: A flow diverting mechanism for the twin duct offtakes or coannular offtake for a turbo fan engine powering aircraft with either thrust reversing or short takeoff and vertical landing or both capabilities includes a rotary drum mounted between the turbine and afterburner sections and includes ports complementing the inlets in the offtakes to divert the core stream through the offtakes and passages to proportion the fan discharge air utilized for cooling purposes in the engine to cool the liner and walls of the offtakes and the engine components located downstream of the rotary drum while assuring separation of the core stream flow and fan air flow.

Abstract: A thrust reverser for a turbojet engine is disclosed having a thrust reverser door and a thrust reverser panel pivotally attached to a housing so as to pivot in opposite directions about the same pivot axis. An epicyclic gear mechanism interconnects the housing, the thrust reverser door and the thrust reverser panel such that the thrust reverser door and the thrust reverser panels move in opposite directions about the common pivot axis when moving between their forward thrust and reverse thrust positions.

Abstract: The control system comprises a plurality of nozzles pointing in different directions, a plurality of gas generators, and pipework connecting the gas generators to the nozzles via gates for allowing or preventing gas being ejected therethrough. Each gas generator is fitted with a shutter disposed in an outlet passage connecting the generator to the pipework, the shutter having a closed position in which it closes the outlet passage by bearing against a seat formed in the passage and against which it is pressed when the generator is not ignited so as to isolate the gas generator in sealed manner from gas contained in the pipework and coming from other generators, the shutter being automatically lifted off its seat to move from the closed position to an open position under the effect of the pressure produced in the generator in response to being ignited, thereby enabling control to be performed with gas generators being ignited independently of one another.

Abstract: The present invention is a thrust reversing apparatus for diverting purely rearwardly directed air flowing through an engine nacelle to combined rearward-and-radially-outward flow, and then to a combination of various radially outward angles and forward flow, where in the latter states thrust reversal is effected. The apparatus includes parallel inner and outer air flow blocking members driven by actuators which are coupled to the blocking members for effecting synchronous movement. The inner member includes a first door having fixed vanes and a solid second door pivotably coupled to the first door. The inner member has a closed position in which the two doors are collinear, and various open positions in which the two doors are pivoted relative to one another. The outer member comprises an array of pivotable, parallel vanes, and has a closed position in which the vanes tightly overlap, and various open positions in which the vanes are pivoted out of contact with each other through various amounts of rotation.

Abstract: A spacecraft has, in addition to redundant thrusters T3, T4 prime thrusters T1 or T2 arranged to be operated one at a time which are supplied with propellant 1 via valves V1 and V2. The thrusters are of the kind in which energy is transferred to the propellant by employing electrodes which create a current flow path through the propellant gas. A single power supply PSU1 provides power to several electrically-powered thrusters. It is connected such that when actuated all the thrusters to which it is connected become charged. However, only the thruster which receives propellant is able to carry current as the propellant forms part of the current carrying circuit, and this thruster therefore draws power. This technique allows the use of a single power supply for several thrusters while eliminating or minimizing the necessity to switch power from one thruster to another.

Abstract: A fluid flow duct such as the jet pipe of an aircraft gas turbine powerplant has alternatively selectable outlets so that thrust may be directed through either an axial discharge nozzle or through vectorable lift nozzles. Side outlets in the jet pipe leads to lift nozzle on port and starboard sides of the aircraft. Nozzle selection is made by means of a composite diverter valve comprising a sleeve valve to cover the side outlets and a segmented blocker valve to close the jet pipe and deflect engine exhaust through the side outlets. The blocker valve segments are carried on the sleeve valve for simultaneous deployment. The segments are adapted to delay the opening of the side outlets as the sleeve valve translates axially. Specially extended segments co-operate with a shaped duct wall adjacent the outlets to delay their uncovering.

Abstract: A flow diverter arrangement for an aircraft comprises a first duct 17 for receiving propulsion fluid from the powerplant 11 and delivering it to a first location 18, a second duct 19 merging with the first duct 17 at a communication aperture 23 and adapted to deliver propulsion fluid to a second location, a flap member 24 pivotted for movement between a first position in which it closes the communication aperture 23 and a second position in which it closes the first duct, and a diverter device 31 for diverting propulsion fluid into the second duct when the flap member is in its second position.

Abstract: A diverter valve arrangement for a fluid flow duct having selectively alternative outlets. In order to avoid an over-area condition during transition an additional valve is provided to delay the effect of operating the main changeover valve. The diverter valve comprises a sleeve valve which covers/uncovers side outlet ports in the duct wall and a blocker valve made up of a plurality of segments pivoted to the inside of the sleeve valve. As the sleeve translates to uncover the side ports the blocker valve leaves deploy to obstruct axial flow. The additional sleeve valve acts as a shuttle and temporarily follows the main sleeve to delay uncovering the side ports.

Abstract: Disclosed is a gas turbine engine which incorporates a vertical thrust nozzle which diverts working fluid from the engine to selectively provide vertical thrust or a combination of vertical and forward thrust.

Abstract: An apparatus for influencing a flow of air through a passageway defined between an inner wall and a double outer wall that includes first and second walls each formed with an opening, comprises a first door, a second door, vortex generation means positioned between the first and second walls and adjacent the upstream end of the opening in the first wall, and an actuator pivotally attached to the first and second doors. The actuator has a first condition wherein the first and second doors close the openings in the first and second walls respectively and has a second condition wherein the first door is at the downstream end of the opening in the first wall and extends across the passageway and directs the flow of air through the opening in the first wall, and the second door is at the down-stream end of the opening in the second wall and deflects the flow of air through that opening.

Abstract: The invention concerns a device designed to modify the trajectory of a projectile by pyrotechnical thrusters, formed by several solid propellant thrusters arranged transversally on a cylindrical support. The combustion chambers, instead of having a cylindrical shape, are parallelepiped shaped. They contain propellant loads which are gone through by a rod connecting a streamlined to the support. The streamlined and the support are cut up to realize nozzles which allow the ejection of gas, the gas coming from the combustion of the propellant load. Thus for a given thickness (e) of the support, a greater loading volume is obtained than that which would be obtained with standard, cylinder-shaped thrusters.

Abstract: An aircraft has two vectorable front nozzles each mounted in a bearing located within the fuselage near an adjacent wing. Each nozzle is rotatable from a first position in which exhaust air is directed downwards to a second position in which the exhaust air is directed rearwards. In the first position the nozzle resides within a cavity formed in the wing root to reduce nozzle drag when the aircraft is propelled by its rear nozzle only. The front nozzles rotate out of their respective cavities to the second position when they are used for forward thrust. Additionally, the cavity is extended to form a passage through which secondary air entrained by exhaust from the front nozzle operating in the first position adds to the vertical thrust and reduces suck down effects.

Abstract: A yaw and pitch thrust vectoring exhaust nozzle includes a spherical collar, and two surrounding clam shells hinged to a gimbal ring and pivotal about an axis perpendicular to the clam shell hinge axis. The clam shells define a variable area nozzle throat (42) which can be selectively directed vertically by rotation of the clam shells about the hinge axis (38), or horizontally by rotation of the clam shells and gimbal ring about the pivot axis (30), thereby biasing the nozzle exhaust flow vector. Divergent flaps (44, 46) further direct the exhaust downstream of the nozzle throat (42).

Abstract: An auxiliary gas generator is used to provide gas for steering and pointing control of a multi-stage rocket motor system to a head or forward end located final interception maneuvering stage. During lower stage operation, this gas is routed through the "Divert" thrusters of the final interception stage through a check valve. When control is not required, the gas can be either dumped through all thrusters or all thrusters can be closed and the gas dumped into the lower stages. As each of the lower stages is burned out, it is discarded. Using one or more gas generating propellant packages provided therein, the final interception stage maneuvers to the target.

Abstract: A thrust vectoring exhaust nozzle (6) is provided with a vent bypass (38) and flow control valve (44) to vent a portion (43) of the exhaust gas (2) only during diversion of the exhaust gas (2) into an alternative gas flow path (18).

Abstract: A plurality of cascade vanes (28, 29, 30) for directing a flow of gas (20) is provided with at least one flow regulating vane (36) which counterrotates with respect to the cascade vanes (28, 29, 30) over a gas flow vectoring range of motion. The cascade vanes (28, 29, 30) and flow regulating vane (36) corotate when moving through an adjacent stowing range of motion for achieving a stowed, gas flow blocking arangement.

Abstract: One problem associated with aircraft using variable cycle engines is how to provide an air intake which is sufficiently large to be able to supply air to both the first and second compressors of the engine during the parallel flow mode and sufficiently small to minimize aerodynamic drag when the engines are operated in the tandom flow mode during supersonic forward flight. This invention overcomes this problem by providing an air intake which combines a blocker door covering a second portion of the duct which communicates with the second compressor and a means of varying the inlet area of the duct such that the area is maximize when the engines are required to operate in the parallel flow mode and minimized during series flow operation.

Abstract: One problem associated with aircraft using variable cycle engines is how to provide an air intake which is sufficiently large to be able to supply air to both the first and second compressors of the engine during the parallel flow mode and sufficiently small to minimize aerodynamic drag when the engines are operated in the tandem flow mode during supersonic forward flight. This invention overcomes this problem by providing an air intake which combines a blocker door covering a second portion of the duct which communicates with the second compressor and a means of varying the inlet area of the duct such that the area is maximized when the engines are required to operate in the parallel flow mode and minimized during series flow operation.

Abstract: In a gas turbine engine powerplant which has a requirement for both nozzle outlet area variation and thrust reversal, there is provided a common actuating means in the form of rams which firstly move a cowl portion so as to open a radial gap and thereby effectively increase the nozzle outlet area, and secondly move reverser cascades in a downstream direction into the gap created by moving the cowl portion. A lost motion device is fitted so as to enable achieving of the former movement without affecting the latter movement until such time as the latter movement is also required.

Abstract: One major problem associated with the design of high-speed vertical take-off or landing aircraft is the requirement to have the front vectorable nozzles of the aircraft deployed in the airstream which passes over the fuselage of the aircraft when they are in use. The nozzles tend to act as air brakes and thus seriously effect the forward speed and flight characteristics of the aircraft. This invention attempts to solve this problem by providing a vectorable nozzle which is rotatable about one axis between a first position in which it is stowed inside a cavity within the aircraft fuselage when not required, and a second position in which it is deployed into the airstream when required.

Abstract: A nozzle structure for a gas turbine power plant for a V.T.O.L. or S.T.O.L. type aircraft includes a main engine and at least one auxiliary engine; the efflux from the at least one auxiliary engine may be directed downwardly or alternatively horizontally through a convergent/divergent nozzle which may be closed off when the at least one auxiliary engine is inoperative.

Abstract: The invention provides a lateral gas jet piloting device comprising at least one pair of diametrically opposite nozzles and a sliding bar comprising bistable pneumatic means ensuring reciprocal movement thereof so that the ends of said bar close alternately coupling ducts disposed between the nozzles and an external gas generator.

Abstract: An engine nozzle construction having a flap nozzle at the end of an engine exhaust duct, said flap nozzle variably controlling exhaust flow providing a primary flow path, said flap nozzle being movable to a position to direct the exhaust flow from said exhaust duct into a peripheral chamber, said chamber having exit openings around it providing for a secondary flow path for the exhaust flow.

Abstract: The invention relates to a thrust nozzle system, especially for steering a rojectile, having a nozzle arrangement (3) which is fed by a propellant source, for example a gas source. The nozzle system is arranged in a housing having at least one exhaust port (11) provided in the housing, and has a control (14) for steering a thrust jet (18) of the nozzle arrangement through the exhaust port. The invention provides a thrust nozzle system of simple construction which is especially suitable for a high miniaturization, and which permits a flexible thrust impulse forming. For this purpose the thrust nozzle system (2) has a rotating nozzle or a swinging nozzle body (3) which is rotatable relative to the housing about an axis, driven by the propellant, for example by the gas stream (P) from the gas source. The drive of the rotating nozzle body is preferably achieved by an acentric thrust nozzle (10) itself. Due to the low mass and hence low inertia of the nozzle body (3), it may be caused to rotate fast.

Abstract: A valve for selectively changing the direction of flow of working fluid through a variable cycle engine which comprises a first and second compressor 14,16 spaced along a flow duct 26. The duct 26 having air intakes 42 leading to the second compressor 16 and outlets leading to nozzles 44. The valve comprising a sleeve 30 axially movable along the duct. The sleeve 30 having openings 31 in it in which are located doors 32. Links 36 are connected to each of the doors 32 so that as the sleeve 30 is moved axially the doors 32 are pulled open to open the air inlets 42 and the outlets and simultaneously obturate the flow duct 26. In a second position of the sleeve 30 the doors 32 and the sleeve 30 close off the air inlets and outlets and open the duct to allow the first compressor to supercharge the second compressor.

Abstract: A seal plate rests along the edge of a moveable flap surface and extends outwardly therefrom into contact with a stationary wall to seal the gap between the flap edge and the wall. The seal plate is hinged for rotation to one end of a pivotable support link which is hinged at its other end to the flap. The gas pressure load on the seal plate presses it against the flap surface and also tends to rotate the support link to press the outward edge of the seal plate against the stationary wall.

Abstract: A thrust reversing system for controlling the fan gases from a thrust producing aircraft engine. The system comprises a first group of blocker doors surrounding the upper longitudinal portion of the engine fan duct; a second group of blocker doors positioned rearward of the first group surrounding the entire engine fan duct; mechanism is provided for translating an upper movable fairing and a lower sleeve section which during translating provides an upwardly directed opening from the fan duct through gas-directing cascades and deploys the blocker doors from a stowed duct wall lining position to a deployed fan gas blocking deployed position.

Abstract: A guided projectile comprising an energy source supplying a gas flow which feeds two pairs of exhaust nozzles, each pair of nozzles being disposed in the corresponding steering plane. Each of these nozzles is provided with a valve for regulating the relative flowrates of the throughflowing gases; this valve being formed essentially by a pivoting vane hinged about an axis; these vanes are interlocked in pairs and positioned by means of two independent mechanisms formed by a deformable parallelogram, the element 40 being the drive element. According to the invention, the directions of the thrust forces created by the nozzles converge at a point P situated on the axis of the projectile and this point P may merge with the center of gravity G of the projectile.

Abstract: A device for bleeding motor gases through the motor pole piece or flange the rocket nozzle flange to reduce the control system weight and complexity and especially for fiber glass wound rocket motor cases.

Abstract: A ducted fan propulsion plant has a reversible-pitch fan driven by a core gas turbine engine and housed in a duct which terminates at its downstream end in an outlet nozzle defined between two semi-cylindrical shells. The shells are mounted for movement hydraulically both axially and angularly to define an increased effective nozzle area for take-off. Upon further rearward axial displacement the shells adopt a reverse-thrust position to define air inlets to the fan when the fan blade pitch is reversed.

Abstract: A V.S.T.O.L. gas turbine power plant includes a main gas turbine engine having an exhaust gas propulsion nozzle and a fan arranged within a fan duct, which duct terminates in two nozzles such that a portion of the fan air may be directed vertically downwards or horizontally, the remaining portion of the fan air acts as a working fluid in one or more further auxiliary gas turbine engines each engine including a vectorable exhaust nozzle.

Abstract: A two dimensional vectoring nozzle assembly has an expandable plug therein including a first pair of panels and a second pair of downstream panels extending between spaced, parallel side walls and wherein a pivoted connection between the first pair of inlet panels and the second pair of downstream panels is located at the nozzle throat and is associated with a mechanism to cause the pivoted connection therebetween to move substantially in a vertical plane at the throat of the nozzle between open and closed positions therein and wherein an exhaust port in the nozzle is selectively opened by a movable door operated between open and closed positions by the mechanism and operative when the expandable nozzle is in its closed position to open the door to concurrently restrict flow through the throat region of the nozzle while opening the exhaust port whereby exhaust flow through the nozzle is directed by the blocking action of the expandable plug from a point upstream thereof through the exhaust opening in the nozz

Abstract: An improvement to an integrated valve assembly which generally consists of a cluster of two poppet valves, four electric-solenoid-operated flapper valves, and four thrust nozzles and interconnecting plumbing. The improvement to the integrated valve assembly reduces the force required to operate the flapper valves thereby minimizing solenoid size, weight, and power consumption. The improvement consists of a modified flapper valve tip having a hole bored through the tip in the direction of tip motion, and a free-fitting piston located therein and suitably axially restrained relative to the flapper valve body.