Abstract: The discharge conduit by which clarified sewage is withdrawn from a sewage clarification plant comprises a headwater conduit section and a low-water conduit section, the latter being separated from the former. The two conduit sections are connected to each other by at least one overground tube, the tube being designed as a siphon. An UV irradiation apparatus is provided for disinfecting the clarified sewage. However, the UV irradiation apparatus is not arranged in the discharge conduit, but is built in into the siphon. This solution has the advantage that the UV irradiation apparatus, which is installed overground, is less susceptible to failure and can more easily be serviced.

Abstract: An integrated turboramjet engine has an axially slidable inlet cone, a rigid guide ring arranged concentrically outside the inlet cone, and a lock ring which can be slid axially against the inlet cone, whereby the air volume flowing into the air inlet can be introduced alternately into a turbo-inlet duct or a ram-air inlet duct in a low-loss and flow-promoting manner.

Abstract: A nacelle for a gas turbine engine (10) defines an air intake which is capable of meeting all the engine airflow requirements. The nacelle comprises a cowling (22), fixed upstream and in spaced apart relationship from an engine cowling (16), to define an annular passage (30) therebetween. Each of the cowlings, (22) and (16), have an air intake, (24) and (20) respectively, through which the mainstream flow of air passes into the engine (10). Depending upon the amount of airflow the engine (10) demands at different operating flight conditions air can flow in either direction through the passage (30). The flow in either direction through the passage (30) enables optimisation of both the internal and external nacelle requirements at all the different engine airflow requirements.

Abstract: An inlet system, which can be used for all supersonic or hypersonic engine inlets, comprises two or several separate parallel ducts which must be switched over in specific phases of flight. This is accomplished with a duct shaped parallel inlet element pivotably assigned to the inlet ramp of the inlet, which as a channel-connecting re-direction member alternately can close off the turbojet inlet duct as well as also the ramjet inlet. Preferably, the construction comprises a plurality of pivotably connected box-like elements interconnected in a movable manner.

Abstract: A variable air intake includes a movable ramp (2) driven by a carriage (6) that moves linearly on a drive screw (7). To protect the drive screw (7) from hot gases a thermal blind (13) is provided that moves with the carriage (6). The blind (13) is guided and supported by guide means (15, 18, 19) formed integrally with a structural unit (17) housing the drive screw (7), and is tensioned by tensioning means (16, 19).

Abstract: With surface sections vaulted with respect to the valve centerline the valve mates with a stationary companion surface on an annular casing lip to optionally shut off or expose the engine by having vaulted surface sections which are arranged at an axial distance an angularly offset over the circumference by essentially 180.degree. with the valve centerline, forming its largest relative diameter; where the vaulted surface sections form a valve of axially and circumferentially three-dimensionally displaced drop or mushroom shape.

Abstract: A turboramjet engine is provided having a ram air duct which is constructed between an outer duct wall and a housing-type shrouding of a basic turbo-engine, and having shut-off devices by means of which the ram air duct, when the basic engine is switched on and the ramjet engine is switched off, is to be shut-off on the air supply side, with the simultaneous release of intake air into the basic engine. In this case, among other things, the shrouding is to form an air shaft which is widened in a polygonal manner in the direction of the inlet-side end of the ram air duct and is to have breakthroughs there, the shut-off devices being flaps which are pivotally arranged at the breakthroughs and which, when the ramjet engine is switched on, expose the breakthroughs and in the process form a shut-off body of the air shaft which is symmetrically acutely folded together with respect to the ram air flow.

Abstract: An hydraulically-pivotable inlet ramp with box-like shaped cross-section for supplying air into engines of supersonic or hypersonic airplanes. The inlet ramp, comprised of a plurality of relatively movable elements, can be adjusted into a number of different positions to optimize air flow under various mach conditions, as well as control a boundary air layer inlet.

Abstract: A nacelle inlet for channeling airflow to a gas turbine engine having a longitudinal centerline axis includes an annular forward nacelle having a leading edge defining an inlet face for receiving the freestream airflow. A diffuser is disposed in flow communication with the inlet face, with the diffuser being defined about a droop axis inclined relative to the engine centerline axis. The forward nacelle includes a crown and a keel defining therebetween a scarf axis, with the keel extending axially forwardly of the crown so that the scarf axis forms an acute scarf angle greater than zero relative to a reference line perpendicular to the droop axis.

Abstract: A bypass valve system includes an annular frame defining a cavity and having an intermediate casing with an annular opening including a plurality of bypass valve doors disposed therein. An annular actuation ring is disposed in the frame cavity and a plurality of space links is pivotally connected between the ring and the bypass valve doors. Each of the space links includes a longitudinal axis and means are provided for rotating the actuation ring between a first position wherein each link longitudinal axis has a first inclination angle and the doors are in a first position, and a ring second position wherein the space link longitudinal axis has a second inclination angle less than the first inclination angle so that the links pivot the doors about a door first end to position the door in a door second position.

Abstract: A bypass valve door includes a pivotable first end, a second end, and an inner surface for facing fluid flow in a bypass valve system. The door includes a seal seat extending obliquely from the door second end. In a preferred embodiment, both the door seal seat and first end are configured for providing seals with adjacent stationary structures when the door is positioned in a closed position. When the door is positioned in an open position, the inner surface is configured for providing an aerodynamically smooth fluid boundary with structures adjacent thereto.

Abstract: A siphon assembly includes a tube connecting a fluid source with a fluid receiver and a priming valve attached to the source end of the tube. The priming valve includes a body having an inlet port and a neck having an outlet port. The inlet and outlet ports are connected by a flow cavity extending through the body and neck. A valve member comprised of a metal ball is received in a seat near the inlet port of the body. Stop ribs are provided in the flow cavity where the body transitions to the neck to receive and centrally position the ball during siphon flow to provide substantially smooth, rapid fluid flow through the valve during siphoning. The body is comprised of a housing and an end ring attached to the housing. The two-piece body may be assembled by welding or alternatively the housing may have an annular flange on its inner surface that mates with a locking tab on the end ring to provide secure attachment.

Abstract: An inlet having a single-piece, flexible inlet ramp skin is disclosed. A corrugated member is rigidly coupled to the interior surface of the ramp skin to hold the skin rigid in one direction but permit it to be extremely flexible in a second direction. A plurality of beams extend perpendicular to the ridges and grooves of the corrugated member to hold the skin in position in the second direction. Mechanical actuators are coupled to the beams for applying force to vary the shape of the beams and thus the shape of the ramp skin. The inlet area is varied as the ramp skin is moved. The beam member and ramp skin are elastically deformable from an intermediate position in a first direction to increase the area of the inlet and in a second direction to decrease the area of the inlet. Shaping the beam and ramp skin to be at an intermediate position when not deformed permits a greater range of movement and a more variable inlet area for a given material and weight.

Abstract: A two dimensional supersonic air intake is provided for the combustion air f an aircraft engine comprising on one side a front flap (3) forming a visor and on the other side a fairing (4). The front flap (3) is movable about a pivoting axis (5) situated opposite the fairing (4). The front flap (3) is fast with a mobile fairing nose (6) situated in front of fairing (4) and moving in front of the latter when the front flap (3) moves in the direction which increases the air intake section.

Abstract: A mixed compression inlet having a forward ramp, an aft ramp, and a slot therebetween is disclosed. The aft ramp is coupled to the inlet to permit both fore-aft movement and rotational movement. The geometric throat of the inlet is located at the leading edge of the aft ramp. The slot opens into a plenum chamber. A vent permits air to exit from the plenum chamber. The pressure in the plenum chamber is maintained approximately equal to the pressure on the aft portion of the forward ramp. A servocontroller receiving input from pressure sensors of the forward ramp and in the plenum chamber controls the position of a vent door to ensure that the proper pressure is maintained within the plenum chamber.

Abstract: A sort of self-fill siphon pipe comprises a straight tube, a hose fitted onto the upper end of the straight tube and in communication with the straight tube, and a one-way valve fitted on the lower end of the straight tube wherein the one-way valve only allows the liquid to enter into the interior of the straight tube. In another form, there is provided inside the straight tube a tubular piston having a one-way valve slidable in the tube. The one-way valve on said tubular piston has a communication direction identical with that of the one-way valve at the lower end of the straight tube. While in use, the straight tube is inserted into the liquid and moves up and down intermittently, the liquid enters into the siphon pipe intermittently through the one-way valve and the siphon pipe is led into the siphon state to automatically suck the liquid.

Abstract: The invention provides a flight attitude control augmentation arrangement and method which is effective at both low speeds and at high altitudes, under conditions in which traditional flight control surfaces cannot provide sufficient air pressure differentials to develop effective control moments. The invention provides flight control surfaces at the engine air intakes of an aircraft. The flight control surfaces are flaps whose angular position determines the amount by which the intake airstream is perturbed by the flap and the consequent reaction force on the aircraft fuselage, which in turn determines the magnitude of the control moments generated by the surfaces. The net moments resulting from asymmetric deployment of the flaps are used to augment flight control moments generated by conventional flight control such as a rudder.

Abstract: The present invention relates to turbofan gas turbine engines. In conventional high bypass ratio turbofans the large variations in the free air stream flowing into the fan duct inlet is accommodated by a thick lip and a long, thick fan casing to prevent air flow separation from the outer surface of the fan casing, but produces a heavy fan casing and large drag values. In the invention a turbofan comprises a core engine which has a core casing, and a fan assembly positioned downstream of the core engine. The fans operate in a fan duct defined by the fan casing. The core casing has an external form upstream of the fan duct inlet which affects the airflow streamlines flowing into the fan duct inlet to cause it to adopt a flow path which is near alignment with the length of the fan casing to reduce fan casing weight, length and drag.

Abstract: An air intake system of an aircraft is improved so that a performance of the air intake system will not be degraded even during flight at a large angle of attack and at high mobility of the aircraft while at the same time secretiveness or security of the aircraft against radar beam irradiation from below will be maintained. The air intake system includes a main air intake port provided on an upper surface of the airframe of the aircraft, an auxiliary air intake port provided on a lower surface of the airframe, and a closure member for the auxiliary air intake port and which is movable between a closed position and an open position of the auxiliary air intake port.

Abstract: Disclosed is an apparatus and method for locating the position of a normal shock in a fluid flowing in a duct.

Abstract: A turbine plant intake housing includes an outer shell supporting radially extending arms which include a fixed part and a movable flap associated therewith. Each arm is provided with a metal tie rod having its radially outer end fixed between two forks supported by the outer shell, and its radially inner end co-operating with a metal insert embedded in layers of coiled filaments of composite material forming a floating hub supported by the tie rods. The radially inner end of each rod is attached to the insert of the hub by use of a nut which effects a prestressing clamping of the tie rod on assembly.

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: 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: The inlet of a jet engine is equipped with a pivotally displaceable deflector which becomes deployed when the aircraft is in a stalled, horizontally stabilized condition. As the aircraft undergoes vertical descent, vertically impinging airflow is reflected off the interior surface of the deflector and flows coaxially through the inlet thereby forcing continued rotation of turbine blades. Hydraulic and electronic control devices deriving power from the turbine may be maintained operative even though the aircraft is in a stalled condition, thereby permitting limited horizontal maneuvering of the aircraft as the vertical descent continues.

Abstract: Air is blown into an air boundary layer to re-energize the boundary layer prior to its ingestion by an engine inlet (12) of a supersonic aircraft (10).

Abstract: A nacelle structure (14) for a gas turbine engine (4) extends upstream from the engine air inlet (10) and includes an external surface (18) and an internal surface (16). The external surface (18) is concentric about a linear centerline (22) which is disposed parallel to the free airflow stream (6) encountered by the nacelle (14) in flight. The internal surface (16) is concentric about a curved centerline (30), the curved centerline (30) being parallel to the free airflow stream (6) at the nacelle inlet (12) and parallel to the engine centerline (26) at the engine air inlet (10) for smoothly directing the internal airflow stream (32) into the engine air inlet (10).

Abstract: The invention is an improved inlet particle separator for removing extraneous matter from a stream of air directed into the engine's core section. The improved separator utilizes two stages of separation. The first stage is an axial flow separator for initially separating engine inlet air into a first flow of relatively contaminated air and a second flow of relatively clean air. This first stage of separation is accomplished by sharply turning the air flow radially inwardly so that the relatively dense extraneous matter continues in its original direction into a scavenge system. A second stage of separation is accomplished in the scavenge system and comprises a centrifugal separator that separates the first flow of air into third and fourth flows of relatively contaminated air for the purpose of protecting a blower that powers the flow through the scavenge system and which is in flow communication with only the relatively less contaminated fourth flow of air.

Abstract: A ram constriction vane diffuser adapted as an air intake of an air plenum-engine pod wherein vertical multiple vanes are fitted on the vertically inclined air intake opening and include fixed vanes positioned adjacent the centerline portion of the air plenums which define an envelope for the airflow including nozzles locate on both sides of a jet engine, a plurality of deflectable vanes positioned in an equally spaced relationship in the air intake openings on both sides of fixed vanes, and wherein each deflectable vane has a leading edge and a drivable trailing section pivotally mounted on the rigid leading section of the deflectable vane and with the drivable trailing sections of each vane and with an actuator for adjusting the angle of the deflectable vanes relative to the freestream air flow for enabling the drivable trailing section of each vane to be turned away from a parallel position to the centerline of an engine suction diffuser, which is the original position thereof for speed flight, to reduce t

Abstract: Aerodynamic flow conditions at the air intake of gas turbine engines, espally aircraft engines, comprising boundary layer deflectors are improved by movably arranging the boundary layer deflectors so that they may be retracted flush into the aircraft fuselage during take-off and low speed flight, and may be extended to an operating position during high speed flight. A similar retractable boundary layer deflector may be provided for an air intake for an auxiliary engine, which operates intermittently to drive auxiliary devices of an aircraft. When the auxiliary engine operates the air intake is open and the deflector is extended thereby improving the intake air flow conditions. When the auxiliary engine is shut down, the air intake is covered by a control flap and the deflector is retracted flush into the fuselage.

Abstract: Siphon assembly for a flushing cistern is in two parts; the first including the down leg of the siphon duct the lower end of which is mounted in the cistern base and the second including the up leg and the inlet chamber in which the flushing piston is received. The parts are releasably connected by a push fit spigot and socket joint secured by a removable pin received transversely through locating formations on each part near the tops of the legs, further formations near the bottoms of the legs being received in vertical sliding relationship.

Abstract: A diffuser for an air intake of an aircraft has an inlet and an outlet, both with variable cross-sectional flow areas. At least one wall section of a diffuser defining flow channel is movable by one or separate lever linkage systems for varying the inlet and outlet cross-sectional flow areas. A control circuit, preferably a closed loop control circuit responsive to a control program, makes sure that optimal flow cross-sectional areas are maintained at the inlet and outlet of the diffuser to optimize the operation of the diffuser.

Abstract: A valve (10) for a water temperature control system having a heat exchanger (C), a tank (T), and a pump (P) for circulating heat transfer fluid through a supply line (11, 12, 13) from the tank to the heat exchanger and through a return line (14, 15) from the heat exchanger to the tank including a valve housing (20) interposed in both the supply line and the return line having supply inlet and supply outlet connections (24, 25), having return inlet and return outlet connections (26, 28), and having first and second drain connections (29), a valve element (45) associated with the valve housing having a first position for normally circulating the heat transfer fluid from the supply inlet connection to the supply outlet connection and from the return inlet connection to the return outlet connection and having a second position discontinuing circulation through the supply inlet connection and the return outlet connection and connecting the supply outlet connection to the first drain connection and the return outle

Abstract: A two-dimensional inlet for a high speed ram jet missile includes in combination an educated slot and a single ramp for varying the geometry of the inlet.

Abstract: An axially semisymmetrical supersonic air intake comprises a semiconical reaction engine displacer body having an air gap between the flat bottom of the air intake of the displacer body in the outer contour adjacent thereto of a missile or aircraft. The body transmits the boundary flow of the missile or aircraft and is bridged by a boundary layer plow. The body has a circumferentially distributed aperture on its surface in a zone of external normal shock which is produced during the subcritical conditions oscillating back and forth by which communication is established with the bleed air channel. The bleed air channels lead openings in the body to the flat bottom and may be subdivided by partitions in the interior of the body into individual parallel passages. The channels are formed by semiconical air baffles which are coaxial with the displacer body and taper in a direction opposite to the taper of the displacer body.

Abstract: An air inlet for an aircraft engine is disclosed. The inlet includes a nacelle and a fairing spaced therefrom for defining an inlet duct to the engine. The fairing includes a plurality of inlet apertures in flow communication with ambient air and the nacelle includes at least one outlet aperture which is also in flow communication with ambient air. A plurality of struts extends between the fairing and the nacelle and a plurality of flow channels is provided therein, each extending in flow communication from respective ones of said inlet apertures through said struts and nacelle and to said outlet aperture. During operation, the air inlet receives air, and a portion thereof adjacent to the fairing is channeled through the inlet apertures and flow channels out the outlet aperture into the ambient air flowing over the nacelle to bleed off relatively low pressure recovery air.

Abstract: A hand held and hand operated device is capable of pumping or siphoning a liquid. The device includes a pair of telescoping hollow tubes having a single longitudinal axis with a seal therebetween that is maintained when one of the tubes is reciprocated relative to the other. Each of the tubes has a conical valve seat at its distal end with each conical valve seat having the same selected angle to the single longitudinal axis of the tubes. Each seat has a separate stainless steel ball to seal on the seat whenever the longitudinal axis of the tubes is at a greater angle to the horizontal than the selected angle of each conical seat to the longitudinal axis. In this position, reciprocation of the tubes causes pumping of the liquid through alternatively removing each of the balls from its seat due to pressure differentials created by changing the volume within the tubes between the balls.

Abstract: An airflow particle separator for a gas turbine engine provided for removing foreign particles and moisture from the air flow. The separator comprises an inner wall and an outer wall defining a passageway therebetween, with the inner wall including an inlet portion diverging in a downstream direction away from the separator axis while converging towards the outer wall to form a throat to accelerate incoming air to a higher velocity in a substantially axial direction. The inner wall then converges towards the separator axis and diverges from said outer wall with a splitter ring disposed between the inner and outer walls for splitting said passageway into inner and outer passages, with the outer passage adapted to bypass moisture and foreign particles. The leading edge of the splitter ring is located downstream and inward of said throat.

Abstract: A device, particularly for use with guided missiles, of a type having an intake pipe which is not fully rotationally symmetrical and is particularly semi-rotationally symmetrical, having particularly a semi-rotationally symmetrical air intake cross-section. The device prevents hum in the supersonic intakes of air-breathing reaction engines, particularly, ram jet engines, of a type which are operated with solid fuels and without regulation of the amount of air intake, the amount of fuel or the amount of thrust current flow for driving guided missiles. The construction includes a missile body having an intake pipe mounted thereon with a front opening disposed in an opening plane defining an inlet. A displacement body is mounted within the pipe in spaced relationship thereto and has a front pointed end which extends outwardly beyond the intake plane and which projects into the incoming air flow.

Abstract: An air intake for a helicopter mounted gas turbine engine comprises two intake portions which comprises vortex separator panels. One panel is generally forward facing while the other is generally sideways facing. A panel is pivotally mounted between the separator panels so as to pivot between a first position in which it obturates the generally sideways facing panel and a second position in which it obturates neither of the separator panels. The arrangement is such that when the helicopter is in fast forward flight, the pressure of the ram air flow through the generally forward facing inlet panel causes the pivoted panel to pivot to the position in which it obturates the generally sideways facing inlet panel.

Abstract: A swimming pool siphon for draining above the ground swimming pools. The siphon is comprised of a generally U-shaped tubular construction having two legs connected by a top bight portion restable upon a top edge of the side wall of the swimming pool. The leg ends are supportable upon the ground and the pool floor and have removable closure caps while a fill cap is provided upon the bight portion. A pool leg may also be provided with a flattened end to drain water closely to the pool floor. After filling the fill cap is closed and siphoning commences upon the removal of the closure caps. The drain leg may be bent or rotated for use with in ground swimming pools and leg extensions may be added as needed.

Abstract: A vented cowl variable geometry inlet for aircraft which provides means to permit starting an overly contracted inlet by dumping sufficient air to obtain the start, as well as to dump air when no thrust is required, but without loss of combustion, and to effect operation of an aircraft of piloted or missile character in a regime where reduction in fuel flow and thrust is advantageous.

Abstract: A compression-sealed door assembly for use in controlling air flow pressure levels within a supersonic jet nacelle inlet, wherein substantially U-shaped strips of resiliently compressible material is compressed between a door and the nacelle inlet to seal air flow passageways through the inlet when the door assembly is pivoted to its fully closed position.

Abstract: A triangular airfoil plate is forward of and below the air intake duct of an aircraft-mounted gas-turbine engine, and a small airfoil member is below the airfoil plate. An inductive action of leading-edge separation vortices generated from the leading edges of the airfoil plate and the small airfoil member is utilized to curve the direction of air flowing into the air intake duct and thereby to prevent turbulence in the intake airflow and resulting defective operation or failure of the engine during flight of the aircraft at large angles of attack.

Abstract: An air inlet and scoop for aircraft auxiliary power units to provide satisfactory performance thereof under all operational conditions, including full capability for in-flight starting at high altitudes, whereby operational difficulties caused by thick boundary layers and adverse pressure gradients between the inlet and the tail cone in the vicinity of the inlet are overcome. The inlet opening is contoured along its outer edges to conform to the aircraft fuselage and has a ramp trailing inwardly into the opening, starting at the fuselage and forming the bottom surface of the inlet. The inlet has generally parallel side walls trailing inwardly, the inlet side walls extending inwardly from the fuselage edges along the inlet opening. A scoop is hinged adjacent the fuselage at one end of the inlet opening, the aircraft having means therein to operate the scoop so as to open and close the inlet opening.

Abstract: A siphon for transferring fluid from a container to either another container at lower elevation or to a disposal area. The siphon includes a tube having an improved one way check valve which valve is inserted into the first container and, by merely shaking the tube up and down, fluid flows by gravity into the second container or disposal area. The valve includes a valve housing having a throughbore with one end of the housing coupled to the tube and the other end mating with an internal movable cup-shaped element to thereby prevent fluid flow past the element when seated in the other end of the valve housing while permitting fluid flow through the valve housing and into the tube when the element moves away from its seating position.

Abstract: Apparatus for siphoning liquid such as water which accumulates in a ponding area (16) located on a flat roof (12) to a drain (14) is disclosed. The apparatus includes a first liquid conduit (21) which has one end (58) in the accumulated water and a second end (52) in drain (14). A reservoir (26) (64) accumulates a selected volume of water which is transferred from the reservoir (26) (64) by a second liquid conduit (38) to the first liquid conduit (21) such that the first liquid conduit (21) is completely filled with water suitable for initiating siphoning action of the water in ponding area (16) to drain (14). A means for controlling the flow of liquid from reservoir (26) (64) to first conduit (21) such as float valve (36) is included such that there is no transfer of liquid from reservoir 26 to first liquid conduit 21 until the selected volume of water has accumulated.

Abstract: A water power unit for a dam which includes a downwardly directed conduit for directing water from the body of water from the body of water retained by the dam to a water turbine or the like for generating power, the conduit including an upstanding U-shaped section having a bight portion extending above the level of the body of water together with a pump for pumping water entering the conduit around a check valve in the conduit to initially fill the conduit U-shaped section with water so that an increase is obtained as water flows in the conduit to increase the power output of the turbine together with a siphon action obtained within the U-shaped section during the operation of the turbine for further power increase.

Abstract: In an air inlet for a gas turbine jet propulsion plant in which the inlet annel is curved, separation flow is generated near the inner wall surfaces of the inlet at certain angles of attack. A flow guide fence is employed which reaches into the air inlet channel a small extent radially so that separation flow is caused to follow the channel and substantially dissolves itself by the time it reaches the compressor entrance so that flow to the compressor is substantially homogeneous.

Abstract: A smooth surfaced, submerged air inlet for use generally forwardly of an engine in an aircraft (missile or other air vehicle). The inlet has an opening having wall surfaces adapted to be flush with or inwardly of an aircraft body surface. The wall surfaces of the opening have a leading and outer end in a plane and the surfaces extend inwardly to form an uncovered shallow channel-shaped portion to the inlet, the channel portion deepening inwardly in the trailing direction and continuing into a partial ellipse portion of the opening. The ellipse portion deepens inwardly as it extends in a trailing direction and has substantially parallel wall surfaces extending outwardly of the ellipse in the direction toward the level of the plane. There are extensions of said substantially parallel wall surfaces diverging outwardly to said plane.

Abstract: A variable inlet for a marine jet propulsion system comprising a movable lip, a center splitter serving to divide said inlet into upper and lower passages and coupled for movement proportional to that of said lip to assure equality of the areas of said upper and lower passages, and apparatus for varying the outward projection of said splitter to vary the diffusion ratio of said upper and lower passages.