scope:

Abstract:

Following rework of the Magellan Power Control Unit (PCU), an engineer performed an after-hours test of the unit without quality assurance assistance or adequate test procedures. Reverse polarity voltage was applied to electronic circuitry within the unit, causing blown fuses and potential damage to electronic parts. Test or retest of flight hardware should always be performed with adequate personnel in attendance, with QA surveillance, and with approved test procedures. Prior to tests, review the use of test instrumentation to verify the proper configuration and precautions.