One of the key workhorses of the Shuttle Orbiter fleet’s engineering, the Main Propulsion System (MPS), proved to be one of the unsung stars of last week’s launch of STS-121.
A hold was nearly called for the T-31 second mark, due to concerns about the liquid oxygen (LOX) inlet temperatures proving to be higher than normal. However, engineers made the call that the MPS turbo pumps could cope – and Discovery launched as planned without issue.