Engineering studies on non-nuclear reactor assemblies (simulators) were made as follows: Reactor Simulator for Startup Development (RSSD) This simulator duplicates stored heat capacity and flow impedance of the reference reactor during an initial startup and restart transient. RSSD is to be a part of the Cold Flow Development Test System (CFDTS), which is in the planning stage of Aerojet-General Corporation's effort in propellant feed system control development. Reactor Simulator for ETS Flow Test This simulator is to be a part of E-engine simulator which would be used to check out installation details and to test flow interaction of the engine and the test stand facility (piping and ejector systems) at ETS-1 and 2. The reactor simulator is similar to RSSD except that the restart capability is not required.