Search NASA⌕ Search

Engineering topics

Webb, B. J.

Publications and source records attributed to Webb, B. J..

PEGASUS - A multi-megawatt nuclear electric propulsion system

A propulsion system (The PEGASUS Drive) consisting of a magnetoplasmadynamic (MPD) thruster driven by a multimegawatt nuclear power system is proposed as the propulsion system for a manned Mars mission. The propulsion system described is based on a mission profile containing a 510-day burn time (for a mission time of approximately 1000 days). Electric propulsion systems have significant advantages over chemical systems, because of high specific impulse, lower propellant requirements, and lower system mass. The thermal power for the PEGASUS Drive is supplied by a boiling liquid-metal fast reactor. The system consists of the reactor, reactor shielding, power conditioning, heat rejection, and MPD thruster subsystems. It is capable of providing a maximum of 8.5 megawatts of electrical power of which 6 megawatts is needed for the thruster system, 1.5 megawatts is available for spacecraft system operations and inflight mission applications, leaving the balance for power system operation.

Coomes, E. P.↗

The Pegasus drive - A multi-megawatt nuclear electric propulsion system

Pegasus, a power generating system for use in space, is multimegawatt power system that would enable missions of almost any conceivable duration and scope. The Pegassus Drive is the coupling of this nuclear electric power system with a 6 MWe MPD thruster. The power system has a maximum power output of 8.5 MWe. The MPD thruster requires 6 MWe to provide spacecraft propulsion and 1.5 MWe are available for mission-specific tasks and experiments. The balance of power generated is used to operate the power system. The size and mass limitations of the STS are of prime consideration in the design of this system to allow the collapsed system to be placed in lower earth orbit by two Shuttle missions. The main system (19,120 kg) employing a shadow shield would require one launch and the balance of the four-pi shield (27,830 kg) would occupy the second launch. Development of this power system could be completed by the mid 1990's and the system available near the turn of the century.

Coomes, E. P.↗