STS-41-D Discovery being rolled back to the Vehicle Assembly Building (VAB).
Following the launch abort at T-6 on June 26, 1984, it was discovered there was a problem with SSME #3, which had some contamination in a hydraulic actuator, this in turn led to a temporary blockage of the engine’s hydrogen fuel valve. NASA decided to change out the complete engine on the pad. However, it was decided to combine the Discovery's first (STS-41-D) and second (STS-41-F) missions and payloads together to minimize satellite backlog after the PAM-D failures during STS-41-B. This required the Space Shuttle to be de-stacked from the ET and sent to the OPF. There workers installed additional support for the new payload. Discovery returned to the launch pad on August 9.
Date: July 14, 1984
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