How about this engine series?<br /><br />Powell is the inventor of the Particle Bed Reactor (PBR), which was the basis for the SDI program to develop an ultra lightweight Nuclear Thermal Propulsion (NTP) engine for defense applications. The PBR NTP engine components were developed and tested by a National LaboratoryIndustry team (Brookhaven National Laboratory and Sandia National Laboratory, together with Grumman, Babcock & Wilcox, Garrett, Hercules, and General Dynamics). The PBR engine would have delivered 200,000 Newtons of thrust, with an engine weight of 500 kg and a specific impulse of 1000 seconds from its 3000 K hydrogen propellant. The PBR effort was carried out from 1987 to 1992 at a cost of 200 million dollars. The program was on track to ground test a full up engine, with a flight test in 1997, when the end of the Cold War caused the program to end.<br /><br />Since then, Powell has continued to work on compact NTP engines for future robotic and manned NASA missions. Plus Ultra Technologies has published a number of papers on the compact MITEE (_MI_nature Reac_T_or _E_ngin_E_) and received several NIACNASA study contracts. The MITEE engine has a number of significant innovations over the PBR engine. It has bi-modal capability, with 14,000 Newtons of thrust in the NTP mode and 20 KW(e) in the electric generation mode, it uses a more durable nuclear fuel (the tungstenUO_2 cermet fuel developed for the 710 engine), and a modular easily scalable pressure tube construction. The total weight of the bi-modal engine is only 200 kilograms for 14,000 Newtons, 20 KW(e) output.<br /><br />Plus Ultra has also developed a new approach for an ultra lightweight nuclear electric space power system that is based on existing navy reactor fuel and the standard steam power cycle. The SUSEE system achieves 25% cycle efficiency (thermal to electric) with a total system weight (reactor, turbine-generator, and radiator) of only 3 kg per KW(e). The key innovation for the SUSEE sys <div class="Discussion_UserSignature"> <font color="#993300"><span class="body"><font size="2" color="#3366ff"><div align="center">. </div><div align="center">Never roll in the mud with a pig. You'll both get dirty & the pig likes it.</div></font></span></font> </div>