Aerodynamic heating effects on a flying object at high speeds

In a research project held by TUBITAK SAGE, temperature, pressure, and acceleration values were measured on an external store carried under a wing of an aircraft at various flight profiles. To choose the right sensors and devices for such flight tests, it's important to know the temperature limits that all the devices might be exposed to. This is because each sensor has optimal performance in some tight temperature levels, and does not function at all when its temperature limits are exceeded. Flight speeds and altitudes of the flight profiles were well defined before the tests. When the sea level temperature is known, corresponding temperature values of different altitudes can be calculated easily. Literature surveys show that the dominant factor affecting the outer surface temperature of flying objects at high speeds is not the ambient air temperature but the aerodynamic heating effect. There are a few equations available in the literature to calculate the aerodynamic heating as a function of the ambient air temperature and the flight speed.. These equations are presented in some papers and books, but verification of them couldn't be found. Therefore how confident they are and the accuracy level of the equations are not clear. Before the flight tests, detailed heat transfer analysis of the external store and the devices in it were done using the mentioned equations. The temperature measurements taken during the flights were compared with the analysis and the verification of the equations were done. In this paper, the equations, calculations, test data and comparison of the results were presented. Finally a conclusion was made about the accuracy level of the equations given in the literature.