A method is set forth for the computation of test-section, aftershock, and stagnation conditions in hotshot tunnels of Arnold Engineering Development Center, using nitrogen at stagnation temperatures from 1500 to 5000 o K. The basic input data are the stagnation pressure in the res2rvoir, the pitot pressure be~ind a normal shock, and the heat-tran.-3fer rate at the stagnation point. The value of the overall enthalpy is adjusted by numerical iteration until the measured and computed heat-transfer rates are numerically equal within a prescribed tolerance. PUBLICATION REVIEW This report has been reviewed and publication is approved.