In the 1960s much research was conducted in the United States on nuclear thermal rocket propulsion technology. The culmination of this was Project NERVA. Between 1955 and 1972 the US ran Project ROVER, to investigate the application of nuclear thermal rocket technology to space propulsion. There were three main phases to the ROVER program which included KIWI, Phoebus and Peewee. These were then followed by the NERVA program which was an initiative to build a flight ready model. The NERVA program had the following objectives: multi-mission capability, man-rated, based on full-flow topping, minimum chamber temperature of 2,360 K, minimum chamber pressure of 450 psi, minimum 75,000 1b thrust, endurance of 600 minutes and up to 60 cycles. Capable of 85,000 1b and 500 psi transients, incorporating adequate shielding for manned operations, storable for 5 years on the ground, 6 months on the pad, and 3 years in space, transportable by land, sea and air.
The culmination of the NERVAprogram was NERVA-2 which had the specification of 10.55 m diameter, 43.69 m length, 34,019 kg empty mass, 178,321 kg full mass, 867,000 N thrust, 825 s vacuum specific impulse, 380 s sea level specific impulse, 1,200 s burn time. Sadly, Project NERVA came to an end, and this is despite the obvious applications for future Mars missions.
So it was that in 2013 Stellar Engines Ltd starting looking at Nuclear Thermal Propulsion technology. This was given the name Project STRAND or Scaled Thermal Rocket and Nuclear Demonstrator. This had the function of designing and building a scaled nuclear thermal rocket engine, by simulating the reactive core element by the use of an electrical heating system. Project STRAND would represent a 500 MW power output system, just like the historical Peewee design. The aim of Project STRAND was to ignite interest in nuclear thermal propulsion technology in the UK and Europe, as a means to building a consensus for essential policy changes which would see the application of nuclear based together for deep spaceflight and planetary missions. Another function of a scaled nuclear thermal rocket demonstrator is to act as an educational vehicle, for both College and graduate level students, in order to teach them about nuclear propulsion capabilities which are expected to become more important for future space missions. No facility currently exists to provide such a platform.