NERVA nuclear rocket engine family

NERVA is the historical nuclear-thermal rocket engine development line associated with NASA and the Atomic Energy Commission’s NERVA programme. A fission reactor heated hydrogen, which expanded through a nozzle to produce thrust. Hardware progressed from NRX reactor-engine experiments to the XE flight-geometry experimental engine. Ground testing addressed the reactor, turbopump, propellant feed, startup, control and restart behaviour. The line never reached a flight test before programme cancellation in 1973. Different experimental engines and proposed flight designs had different power and thrust ratings.