scope:

Abstract:

The over-current detection scheme for Deep Impact spacecraft heater circuitry failed to detect an over-current condition during ground test due to an inadequate circuit design and test design. The root cause was inadequate contractor oversight and peer review. The lessons learned from the MCO mission loss on the value of detailed technical review and contractor oversight must be reemphasized, and test configurations should be subjected to FMEA and feature positive controls limiting electrical current.