1. The stagnation temperature in the reservoir region is being restricted to a reasonably low value to minimize air dissociation. A baseline stagnation temDerature of 3000 K is currentlv beina considered. The static temperature is ' then maintained low (on the order of 1500 to 2000 K) through the system to the accelerator exit.
2. The major accelerator operations. experiments that have been conducted in the United States are discussed below. v There are some indications that MHD accelerator experiments have also been conducted in other countries. MHD accelerator experiments using alkali metal seed materials in the plasma to enhance the ionizationhave been conducted by a number of organizations, including NASA Langley Research Center, the Arnold Engineering Development Center (AEDC), and The Aerospace Corporation. Unseeded experiments were conducted by the General Electric Company. These experimental investigations were conducted almost exclusively in the 1960's.