Book Description

Tests carried out on a short static probe at supersonic speeds between Mach numbers of 1.1 and 2.5 are described. The probe consists of a 50 deg included angle cone-cylinder having sensing holes 0.88 calibres aft of the cone-cylinder junction. The tests show that at zero incidence the probe measures a pressure (approximately independent of Mach number) of 0.793 times the local static pressure. They also show that, at up to 18 deg incidence in any pitch plane, the pressure measured is 0.763 plus or minus 0.03 times the local static pressure. For a limited Mach number range near a Mach number of 1.6, this accuracy can be maintained to incidences over 30 deg. Of particular interest is the fact that relatively small internal differences between externally identical probes appear to have a significant effect on the incidence characteristics and in some respects can improve the performance. (Author).