Comparison of inflight experiences and system design expectations of the AMSAT Phase III B spacecraft

The design and performance of OSCAR 10 (AMSAT P3B), an amateur-radio transponder satellite launched on June 16, 1983, are reported. The 135-kg satellite has two transponders for up to 300 voice channels, a 400-N two-liquid propulsion system, and a completely reprogrammable computer with a 16-kbyte shielded dynamic memory. Drawings of the satellite and a functional block diagram are provided. The command and communications functions permitted reprogramming and maneuvering after a collision with the third stage of the Ariane launch vehicle. Due to a helium leak, the motor could be fired only once, so that the final orbit had an inclination of 26 deg instead of the intended 57 deg.