Typical stagnation conditions required to simulate the orbital re-entry corridor are P0 > 1000 atm and T0 > 5000°K. Although it is not feasible to have such stagnation conditions in a reservoir operating under nearly continuous conditions, it is feasible to obtain high stagnation temperatures in a gas flowing from a relatively cool high-pressure reservoir by adding laser energy to the flow. In this new approach, two important advantages are realized: 1) the energy source (i.e., the laser) is physically separated from the wind tunnel and is not temperature-limited as compared to direct heating devices, and 2) the laser beam can be accurately aimed down the central core of the flow, avoiding direct heating of the tunnel walls. A conceptual wind-tunnel configuration is illustrated in Fig. 1. The laser beam enters the tunnel system through a window near the plenum chamber and propagates downstream through the subsonic flow region of the nozzle. Under reservoir con-