Multi-pulse propulsion system with passive initiation

A flight vehicle comprising:

• a payload;
• and
• a multi-pulse propulsion system, the multi-pulse propulsion system comprising:
• at least one pulse chamber containing at least one propellant for igniting during at least one pulse of the multi-pulse propulsion system;
• a first igniter configured to initiate the at least one pulse by igniting the at least one propellant contained in the at least one pulse chamber, wherein the first igniter being controlled by a main system controller;
• at least one additional pulse chamber containing at least one additional propellant for igniting during at least one additional pulse of the multi-pulse propulsion system, wherein the at least one additional pulse is subsequent to and separate from the at least one pulse, wherein the at least one additional propellant is not ignited until the at least one additional pulse;
• and
• at least one passive fuzing system configured to initiate the at least one additional pulse, the at least one passive fuzing system comprising a sensor and a second igniter, the sensor being configured to sense an environmental condition and a ballistic condition, and the second igniter being configured to provide a stimulus that causes ignition of the at least one additional propellant in response to the sensor sensing that the environmental condition and the ballistic condition has reached or exceeded one or more threshold values, wherein the passive fuzing system is operable independent of a connection to the main system controller, wherein the passive fuzing system is operable independent of main vehicle electronics that initiate the at least one pulse,
• wherein the environmental condition sensed by the sensor includes temperature or pressure, and
• wherein when a threshold temperature or pressure value is sensed by the sensor, the second igniter is activated to ignite the at least one additional propellant, thereby initiating the at least one additional pulse.

A method of operating a multi-pulse propulsion system of a flight vehicle, comprising:

• sensing an environmental condition of the flight vehicle with a sensor of a passive fuzing system of the multi-pulse propulsion system;
• determining with the passive fuzing system when the environmental condition has reached or exceed a threshold environmental condition value;
• and
• when the environmental condition has reached or exceed the threshold environmental condition value, initiating a first pulse of the multi-pulse propulsion system by igniting a propellant contained in a first pulse chamber of the multi-pulse propulsion system with a first igniter of the passive fuzing system, wherein the multi-pulse propulsion further includes:
• a second pulse chamber containing at least one second propellant for igniting during a second pulse of the multi-pulse propulsion system;
• a main system controller configured to initiate the second pulse of the multi-pulse propulsion system;
• and a second igniter connected to and controller by the main system controller and configured to initiate the second pulse by igniting the second propellant contained in the second pulse chamber, wherein the passive fuzing system is separate from the main system controller and operable independent of a connection to the main system controller, wherein the passive fuzing system is configured to initiate the first pulse independently of initiation by the main system controller, wherein the at second pulse is prior to and separate from the first pulse, wherein the propellant in the first pulse chamber is not ignited until the first pulse,
• wherein the environmental condition sensed by the sensor includes temperature or pressure, and
• wherein when a threshold temperature or pressure value is sensed by the sensor, the first igniter is activated to ignite the propellant, thereby initiating the first pulse.