The excessive heat development on the exterior structure of hypersonic reentry vehicles necessitates the use of heat‐resistant pressure transducers for the measurement of boundary layer pressure fluctuations on the vehicle's surface. An appropriate acoustic probe configuration was developed and tested in windtunnel experiments. The frequency response of the probe configuration to flow excitation was studied under subsonic (M = 0.055) and supersonic (M = 2.92) flow conditions and was found to depend both on the probe interior geometry and on the physical characteristics of the flow. In addition, the influence of heat‐shield ablation on the frequency response was studied under these same conditions. Widnall and Lyon's theory of the dynamics of the probe in the presence of hypersonic flow was confirmed by the experimental findings. [This work was sponsored by the Space and Missile System Organization.]