A solid fuel propulsion system includes a housing, an air inlet configured to enable air to flow into the housing, an air duct, a rotation detonation chamber, and a nozzle assembly. The air duct is disposed in the housing and is in fluid communication with the air inlet. The air duct is configured to supply air for combustion of a solid fuel configured to sublimate into a gaseous fuel mixture. The rotation detonation chamber is disposed in the housing aft of the air duct and is configured to combust the gaseous fuel mixture and air to generate a rotating detonation wave. The nozzle assembly is configured to expand and exhaust the flow prompted by the rotating detonation wave to generate thrust.

The present invention provides a multimode propulsion system, comprising at least one propellant ejector system, a high speed fluid ejection nozzle coupled to a propellant supply provided in the engine, and a propellant-air mixing system comprising at east one fluid intake member having an inlet end and an outlet end, the inlet end being in fluidic communication with the fluid ejection nozzle to receive the propellant ejected from the nozzle.

A jet engine includes an inlet that takes air, and a combustor that burns fuel using the air. The combustor includes a fuel injector and an igniter for igniting a gas mixture of the air and the fuel. The igniter ignites and activates automatically by heat and pressure created by compression of the air that has been taken in through the inlet.

The application relates to a Ramjet solid fuel having an ignition temperature of less than 400 C., the fuel comprising a bis-(ethylene oxy) methane polysulfide polymer (BMPP) and hydroxyl-terminated polybutadiene (HTPB), the copolymer having a BMPP/HTPB weight ratio of from 1/3 to 3/1; and the fuel comprising at least 85 weight % copolymer. The BMPP comprises from 5 to 8 weight percent mercaptan. Furthermore, the BMPP is selected from
HS(RSS).sub.aCH.sub.2CH((SSR).sub.cCSH)CH.sub.2(SSR).sub.bSHa) where R(CH.sub.2).sub.2OCH.sub.2O(CH.sub.2).sub.2 and a+b+c<7; and
H(SC.sub.2H.sub.4OCH.sub.2OC.sub.2H4S).sub.nH where n=7.b)

A solid propellant rocket motor has a tubular casing accommodating a mass of solid propellant material and at least one opening for the space in the casing to communicate with the outside closed by a closing head; the closing head being coupled to the casing by means of one or the other of two blocking portions with different strength both carried by a movement device which can be elastically deformed and operated from the outside.

The application relates to a Ramjet solid fuel having an ignition temperature of less than 400 C., the fuel comprising a bis-(ethylene oxy) methane polysulfide polymer (BMPP) and hydroxyl-terminated polybutadiene (HTPB), the copolymer having a BMPP/HTPB weight ratio of from 1/3 to 3/1; and the fuel comprising at least 85 weight % copolymer. The BMPP comprises from 5 to 8 weight percent mercaptan. Furthermore, the BMPP is selected from

HS(RSS).sub.aCH.sub.2CH((SSR).sub.cCSH)CH.sub.2(SSR).sub.bSHa)

where R=(CH.sub.2).sub.2OCH.sub.2O(CH.sub.2).sub.2 and a+b+c<7; and

H(SC.sub.2H.sub.4OCH.sub.2OC.sub.2H4S).sub.nHb)

where n=7.

The application relates to a Ramjet solid fuel having an ignition temperature of less than 400 C., the fuel comprising a bis-(ethylene oxy) methane polysulfide polymer (BMPP) and hydroxyl-terminated polybutadiene (HTPB), the copolymer having a BMPP/HTPB weight ratio of from 1/3 to 3/1; and the fuel comprising at least 85 weight % copolymer. The BMPP comprises from 5 to 8 weight percent mercaptan. Furthermore, the BMPP is selected from

HS(RSS).sub.aCH.sub.2CH((SSR).sub.cCSH)CH.sub.2(SSR).sub.bSHa) where R=(CH.sub.2).sub.2OCH.sub.2O(CH.sub.2).sub.2 and a+b+c<7; and

H(SC.sub.2H.sub.4OCH.sub.2OC.sub.2H4S).sub.nH where n=7.b)

The present invention provides a multimode propulsion system, comprising at least one propellant ejector system, a high speed fluid ejection nozzle coupled to a propellant supply provided in the engine, and a propellant-air mixing system comprising at least one fluid intake member having an inlet end and an outlet end, the inlet end being in fluidic communication with the fluid ejection nozzle to receive the propellant ejected from the nozzle.

A solid propellant rocket motor (1) has a tubular casing (3) accommodating a mass (5) of solid propellant material and at least one opening (10) for the space in the casing (3) to communicate with the outside closed by a closing head (11); the closing head (11) being coupled to the casing (3) by means of one or the other of two blocking portions (28) (21A) with different strength both carried by a movement device (21,35) which can be elastically deformed and operated from the outside.

A passive bypass for an inlet to a supersonic or hypersonic air-breathing engine allows airflow in the inlet to exit through the cowling when the inlet supplies more airflow than the air-breathing engine demands. The air-breathing engine may be the only form of propulsion or a secondary form of propulsion to reach higher speeds. The passive bypass includes a plurality of lower channels in the cowling that are operatively coupled to the inlet diffuser at an inner surface of the cowling and swept forward towards the throat, a plenum in the cowling operatively coupled to the plurality of lower openings and a plurality of upper channels in the cowling that are operatively coupled to the plenum and swept back away from the throat to an outer surface of the cowling. A serpentine path through the plurality of lower openings, the plenum and the plurality of upper openings allows airflow in the inlet to exit through the cowling when the inlet supplies more airflow than the air-breathing engine demands.