Patent ID: 7404288

Claim:
A hybrid rocket system, comprising: a motor case having a proximal end and a distal end, the motor case defining an interior volume including a combustion chamber at the proximal end, wherein the motor case is configured to hold solid rocket fuel, the motor case having a first nozzle at the distal end; a fuel tank coupled to the proximal end of the motor case, the fuel tank defining an internal volume configured to hold a fluid oxidizer; a partition interposed between the motor case and the fuel tank, wherein at least one access passageway extends through the partition, the access passageway providing exterior access to the interior volume of the motor case or the internal volume of the fuel tank while the hybrid rocket motor is coupled to the fuel tank, wherein the ratio of solid rocket fuel weight to oxidizer weight is maintained within a predetermined range of values and wherein the system operates at a substantially constant specific impulse through the range of values; a conduit fluidly coupling the supply of oxidizer to a second nozzle, wherein the conduit provides a pathway for oxidizer to flow in a downstream direction from the supply of oxidizer toward and into the second nozzle; a pressure regulator coupled to the conduit and interposed between the supply of oxidizer and the second nozzle, wherein the pressure regulator regulates the pressure of oxidizer at a location downstream of the pressure regulator and upstream of the second nozzle to a set point pressure at or below a first pressure, wherein the first pressure comprises the pressure required to maintain the oxidizer in a gas state to ensure that the any oxidizer flowing through the conduit is in a gas state prior to entering the second nozzle; wherein the at least one access passageway comprises a motor case access passageway, the motor case access passageway having a first opening in communication with the interior volume of the motor case and a second opening in an external wall of the partition.