Summary: Skin and structural temperatures have been obtained on the X-1B and X-1E research airplanes under transient aerodynamic heating conditions at speeds up to Mach numbers near 2.0. Extensive temperature measurements were obtained throughout the X-1B airplane, and temperature distributions are shown on the nose cone, the wing, and the vertical tail. Temperatures for the X-1E wing leading edge and internal wing structure were compared with similar data for the X-1B. No critical skin and structural temperatures were obtained on the two airplanes over the range of these tests. Simplified calculations of the skin temperatures in the laminar-flow regions of the nose cone and the leading edges agreed favorably with the general trends in the measured data. The flat-plate skin-temperature calculations in the turbulent-flow regions agreed favorably with the measured data on the nose cone and at the midsemispan station of the wing but overestimated the vertical-tail skin temperatures and also the upper wing skin temperature near the wing tip. The relatively low values of the upper skin temperatures that were measured at the wing tip were believed to be caused by separated-flow effects in this region.