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The solid propellant apogee insertion motor (AIM) on board the United States Air Force P78-2 SCATHA (spacecraft charging at high altitudes) satellite is of the same general design as that of the inertial upper stage (IUS) that will raise payloads from space shuttle orbits to higher altitudes. Therefore, contamination effects arising from the firing of the AIM would be of interest to those concerned with the IUS or other solid propellant rockets as possible sources of contamination. Several of the contamination detectors on the P78-2 satellite were operating prior to, during, and following the AIM burn. These detectors consist of (1) two trays of eight calorimetrically mounted thermal control coatings (TCCs), (2) a temperature controlled quartz crystal microbalance (TQCM), and (3) a retarding potential analyzer (RPA). The data from these sensors have been analyzed to look for contamination due to the firing of the AIM. No contamination was detected with either the TCCs or the TQCM. Some anomalies were noted in the data from the RPA. However, these anomalies, if they actually correspond to AIM-related contamination, represent an upper limit of only 0.8 ng/cm2 at the detector location. Although these instruments are sensitive to molecular contamination, they are relatively insensitive to contamination in the form of particulates. Furthermore, the instruments were not optimally located on the vehicle to detect AIM products. The data do set upper bounds on the condensable molecular contamination that reached two locations on a typically configured satellite during the firing of an intermediate sized solid propellant motor.
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