A system for bistatic radar target detection employs an unmanned aerial vehicle (UAV) having a ramjet providing supersonic cruise of the UAV. Deployable antenna arms support a passive radar receiver for bistatic reception of reflected radar pulses. The UAV operates with a UAV flight profile in airspace beyond a radar range limit. The deployable antenna arms have a first retracted position for supersonic cruise and are adapted for deployment to a second extended position acting as an airbrake and providing boresight alignment of the radar receiver. A mothership aircraft has a radar transmitter for transmitting radar pulses and operates with an aircraft flight profile outside the radar range limit. A communications data link operably interconnects the UAV and the tactical mothership aircraft, transmitting data produced by the bistatic reception of reflected radar pulses in the UAV radar antenna to the mothership aircraft.

The present disclosure is directed to a rotating detonation combustion system for a propulsion system including a plurality of combustors in adjacent arrangement along the circumferential direction. Each combustor defines a combustor centerline extended through each combustor, and each combustor comprises an outer wall defining a combustion chamber and a combustion inlet. Each combustion chamber is defined by an annular gap and a combustion chamber length together defining a volume of each combustion chamber. Each combustor defines a plurality of nozzle assemblies each disposed at the combustion inlet in adjacent arrangement around each combustor centerline. Each nozzle assembly defines a nozzle wall extended along a lengthwise direction, a nozzle inlet, a nozzle outlet, and a throat therebetween, and each nozzle assembly defines a converging-diverging nozzle. A first array of combustors defines a first volume and a second array of combustors defines a second volume different from the first volume.

An engine includes an inlet tube introducing air to a combustion process and a first plurality of fuel injectors disposed in the inlet tube and used for scram-jet engine operation. The engine includes a second plurality of fuel injectors used for ram-jet engine operation. The second plurality of fuel injectors is upstream from the first plurality of fuel injectors and is disposed in the inlet tube. The engine includes a combustor swirl zone downstream of and adjacent to the first plurality of fuel injectors.

An engine includes an inlet tube introducing air to a combustion process and a first plurality of fuel injectors disposed in the inlet tube and used for scram-jet engine operation. The engine includes a second plurality of fuel injectors used for ram-jet engine operation. The second plurality of fuel injectors is upstream from the first plurality of fuel injectors and is disposed in the inlet tube. The engine includes a combustor swirl zone downstream of and adjacent to the first plurality of fuel injectors.

A flight vehicle has an engine that includes air inlet, an isolator (or diffuser) downstream of the air inlet, and a combustor downstream of the isolator. The isolator includes a bulged region that has at least one dimension, perpendicular to the direction of the air flow from the inlet to the combustor, that is at a local maximum, larger than comparable isolator dimensions both upstream and downstream of the bulged region. The bulged region stabilizes shocks within the isolator, and facilitates flow mixing. The flow diversion of high energy flow around the outermost walls of the bulged section into the center of the flow at the aft end of the isolator, increases mixing of the flow, and results in a more consistent flow profile entering the combustor over a wide range of flight conditions (Mach, altitude, angle-of-attack, yaw) and throttle settings.

A flight vehicle has an engine that includes air inlet, an isolator (or diffuser) downstream of the air inlet, and a combustor downstream of the isolator. The isolator includes a bulged region that has at least one dimension, perpendicular to the direction of the air flow from the inlet to the combustor, that is at a local maximum, larger than comparable isolator dimensions both upstream and downstream of the bulged region. The bulged region stabilizes shocks within the isolator, and facilitates flow mixing. The flow diversion of high energy flow around the outermost walls of the bulged section into the center of the flow at the aft end of the isolator, increases mixing of the flow, and results in a more consistent flow profile entering the combustor over a wide range of flight conditions (Mach, altitude, angle-of-attack, yaw) and throttle settings.

An integrated propulsion and warhead system for an artillery round includes a propulsion, such as a solid rocket motor and/or an air-breathing jet engine, and an annular explosive concentrically arranged around at least a portion of the propulsion system. The integrated propulsion and warhead system is included in a propulsion section of the artillery round so that space in an adjacent guidance section is increased and the space allocation for the propulsion system and annular explosive is optimized.

A ramjet projectile comprising: an outer assembly that is tubular and comprises first, second and third portions; solid ramjet fuel attached to and disposed inside the first portion of the outer assembly; an inner assembly disposed inside the outer assembly and comprising a first portion threadably coupled to the second portion of the outer assembly and a second portion surrounded by the third portion of the outer assembly to form an annular air passageway having an air inlet. The first portion of the inner assembly comprising a plurality of openings spatially distributed about a circumference. The inner assembly is rotatable relative to the outer assembly between first and second locations displaced by a distance from each other during travel along the gun barrel. The openings are not in flow communication with the annular air passageway when the inner assembly is at the first location and are in flow communication with the annular air passageway when the inner assembly is at the second location. Preferably the solid ramjet fuel comprises boron and a binder.

A new dual-mode ramjet combustor used for operation over a wide flight Mach number range is described. Subsonic combustion mode is usable to lower flight Mach numbers than current dual-mode scramjets. High speed mode is characterized by supersonic combustion in a free-jet that traverses the subsonic combustion chamber to a variable nozzle throat. Although a variable combustor exit aperture is required, the need for fuel staging to accommodate the combustion process is eliminated. Local heating from shock-boundary-layer interactions on combustor walls is also eliminated.

A new dual-mode ramjet combustor used for operation over a wide flight Mach number range is described. Subsonic combustion mode is usable to lower flight Mach numbers than current dual-mode scramjets. High speed mode is characterized by supersonic combustion in a free-jet that traverses the subsonic combustion chamber to a variable nozzle throat. Although a variable combustor exit aperture is required, the need for fuel staging to accommodate the combustion process is eliminated. Local heating from shock-boundary-layer interactions on combustor walls is also eliminated.