TD-1A investigation into the cause of the failure of the no. 1 tape recorder (TR-1)

The failure of the tape recorder on the satellite TD-1A indicated a fault of a mechanical nature. The recorded data from the satellite was analyzed in an attempt to correlate the results with both a theoretical analysis of frequency sources in the recorder and with results measured on a recorder identical to the TR1. A number of possible mechanisms of failure were artificially induced in the test recorder in an attempt to reproduce the failure symptoms. The failure was shown to be due to a change in tape tension, the cause of which is still unclear but was probably a degradation of the tape lubricant.