Abstract
The recovery factors of miniature bead thermistors as used in meteorological rocketsondes were measured at subsonic Mach numbers using a whirling arm device inside a vacuum chamber. Measured values were near 0.75 at sea level pressure and remained relatively constant with pressure up to a pressure altitude of about 30 km. Above a pressure altitude of 40 km the recovery factors steadily increased with altitude and at 65 km values between 1.10 and 1.45 were recorded.