The heat-transfer characteristics of the laminar compressible boundary layer on a hemisphere cylinder have been investigated at free-stream Mach numbers of 5, 6.5, and 8. The Reynolds number based on free-stream conditions and model diameter was varied from 70,000 to 700,000. Various conditions of steady-state heat trasnfer to the model were realized by circulating a coolant through the model, and by varing the tunnel supply air temperature. The wall to stagnation termperature ratio was varied from 0.43 to 0.75. Optical observations and Pitot pressure surveys of the boundary layer showed it to be laminar on both the hemisphere and the cylindrical afterbody. The heat transfer was evaluated from the temperature differences measured across the model wall under steady-state conditions. Over the hemisphere, the local non-dimensional heat-transfer parameters are, on the average, approximately twnty percent larger than predicted for an isothermal body by Korobkin's modified incompressible theory.

At the stagnation point, the theory of Sibulkin, using the diameter and conditions behind the normal shock, was in good agreement with the experiment when the velocity graident at the stagnation opint appropriate to the free-stream Mach number was used.