A high density, generally recognized as safe hybrid rocket motor is described which has a density-specific impulse similar to a solid rocket motor, with good performance approaching or equal to a liquid rocket motor. These high density hybrid motors resolve the packaging efficiency/effectiveness problems limiting the application of safe, low cost hybrid motor technology.

A multi-pulse gas generator includes a pressure vessel, first and second propellants, a barrier membrane that separates the first propellant and the second propellant, an igniter device that produces combustion gas of igniter charge, and an igniter charge combustion gas exhaust device having exhaust holes configured to exhaust the combustion gas of the igniter charge against the second propellant. The barrier membrane includes: a concavely-deformable portion; and a convexly-deformable portion. A flow rate of the combustion gas of the igniter charge exhausted against a portion of the second propellant located outside of the concavely-deformable portion is larger than that of the combustion gas of the igniter charge exhausted against a portion of the second propellant located outside of the convexly-deformable portion.

A multi-pulse gas generator includes a pressure vessel, first and second propellants, a barrier membrane that separates the first propellant and the second propellant, an igniter device that produces combustion gas of igniter charge, and an igniter charge combustion gas exhaust device having exhaust holes configured to exhaust the combustion gas of the igniter charge against the second propellant. The barrier membrane includes: a concavely-deformable portion; and a convexly-deformable portion. A flow rate of the combustion gas of the igniter charge exhausted against a portion of the second propellant located outside of the concavely-deformable portion is larger than that of the combustion gas of the igniter charge exhausted against a portion of the second propellant located outside of the convexly-deformable portion.

A fission based nuclear thermal propulsion rocket engine. An embodiment provides a source of fissionable material such as plutonium in a carrier fluid having neutron moderating constituents, such as hydrogen and/or carbon, therein. In various embodiments, the carrier fluid may be methane, or ethane, or a combination thereof. A neutron source is provided, such as from a neutron beam generator. By way of engine design geometry, various embodiments may provide for intersection of neutrons with the fissionable material injected by way of the carrier fluid, while in a reactor provided in the form of a reaction chamber. Impact of neutrons on fissionable material results in a nuclear fission in sub-critical mass reaction conditions in the reactor, resulting in release of heat energy to the materials within the reactor. The reactor is sized and shaped to receive the reactants and an expandable fluids such as hydrogen, and to confine heated and pressurized gases for discharge out through a throat, into a rocket engine expansion nozzle for propulsive discharge. The design provides a rocket engine with a specific impulse in the range of from about eight hundred (800) seconds to about twenty five hundred (2500) seconds.

A fission based nuclear thermal propulsion rocket engine. An embodiment provides a source of fissionable material such as plutonium in a carrier fluid having neutron moderating constituents, such as hydrogen and/or carbon, therein. In various embodiments, the carrier fluid may be methane, or ethane, or a combination thereof. A neutron source is provided, such as from a neutron beam generator. By way of engine design geometry, various embodiments may provide for intersection of neutrons with the fissionable material injected by way of the carrier fluid, while in a reactor provided in the form of a reaction chamber. Impact of neutrons on fissionable material results in a nuclear fission in sub-critical mass reaction conditions in the reactor, resulting in release of heat energy to the materials within the reactor. The reactor is sized and shaped to receive the reactants and an expandable fluids such as hydrogen, and to confine heated and pressurized gases for discharge out through a throat, into a rocket engine expansion nozzle for propulsive discharge. The design provides a rocket engine with a specific impulse in the range of from about eight hundred (800) seconds to about twenty five hundred (2500) seconds.

A multipulse rocket motor includes a secondary pulse, fired after a primary pulse of the motor, that includes a thermal insulator having channels therein, around a propellant grain of the secondary pulse. The channels provide a way to equalize pressure on the propellant grain of the secondary pulse, to reduce stresses on the propellant grain as the primary pulse is operating. The channels may extend along most or substantially all of a length of the secondary pulse. The channels may be defined by material strips of thermal insulator material evenly circumferentially spaced around the secondary pulse.

A multipulse rocket motor includes a secondary pulse, fired after a primary pulse of the motor, that includes a thermal insulator having channels therein, around a propellant grain of the secondary pulse. The channels provide a way to equalize pressure on the propellant grain of the secondary pulse, to reduce stresses on the propellant grain as the primary pulse is operating. The channels may extend along most or substantially all of a length of the secondary pulse. The channels may be defined by material strips of thermal insulator material evenly circumferentially spaced around the secondary pulse.

There is provided, in accordance some embodiment, a method for enhancing autorotation performance of a rotary-wing aircraft in emergency events. The method comprises an action of receiving a request for emergency thrust from a user interface. The method comprises an action of sending a start command to an emergency engine coupled to a rotary-wing aircraft following the request. The method comprises an action of thrusting the rotary-wing aircraft coupled to the emergency engine in a direction substantially of a longitudinal axis of the rotary-wing aircraft, thereby enhancing autorotation performance of the rotary-wing air-craft in an emergency event.

There is provided, in accordance some embodiment, a method for enhancing autorotation performance of a rotary-wing aircraft in emergency events. The method comprises an action of receiving a request for emergency thrust from a user interface. The method comprises an action of sending a start command to an emergency engine coupled to a rotary-wing aircraft following the request. The method comprises an action of thrusting the rotary-wing aircraft coupled to the emergency engine in a direction substantially of a longitudinal axis of the rotary-wing aircraft, thereby enhancing autorotation performance of the rotary-wing air-craft in an emergency event.

A high density, generally recognized as safe hybrid rocket motor is described which has a density-specific impulse similar to a solid rocket motor, with good performance approaching or equal to a liquid rocket motor. These high density hybrid motors resolve the packaging efficiency/effectiveness problems limiting the application of safe, low cost hybrid motor technology.