STS-51-A

STS-51-A
NASA · Public domain · source
Name	STS-51-A
Mission type	Satellite retrieval and research
Operator	National Aeronautics and Space Administration
Cospar id	1984-117A
Satcat	15208
Mission duration	7 days, 23 hours, 44 minutes, 56 seconds
Launch date	November 8, 1984
Launch site	Kennedy Space Center Launch Complex 39A
Landing date	November 16, 1984
Landing site	Kennedy Space Center Shuttle Landing Facility
Spacecraft	Space Shuttle Discovery

STS-51-A was the 14th flight of the Space Shuttle program and the second flight of Discovery, notable for the first successful on-orbit retrieval of two commercial communications satellites and extensive extravehicular activity. The mission launched from Kennedy Space Center on November 8, 1984, conducted complex rendezvous and capture operations, and landed at Kennedy Space Center on November 16, 1984, contributing to operational experience used by subsequent Space Shuttle program missions and informing Intelsat and Telesat procedures.

Mission overview

The mission carried out retrieval and return-to-flight operations that combined satellite servicing, payload deployment, and scientific experiments with precision piloting and extravehicular activity; it reflected lessons learned from earlier missions such as STS-41-B and informed policies at National Aeronautics and Space Administration and commercial operators including Hughes Aircraft Company and Eutelsat. STS-51-A involved coordination among Federal Communications Commission, NASA Johnson Space Center, Kennedy Space Center, and contractors like Rockwell International and Grumman Corporation to execute orbital rendezvous, capture, and reboost sequences.

Crew

The seven-member crew blended veterans and first-time fliers from institutions such as United States Naval Academy, United States Air Force Academy, and University of Texas at Austin and included mission commanders and specialists experienced with prior missions including STS-41-D and STS-9. Crew roles invoked training from Johnson Space Center EVA facilities, simulation support from McDonnell Douglas, and flight operations overseen by Mission Control Center (Houston). Notable crew members had affiliations with United States Navy, United States Air Force, and civilian research institutions.

Payload and experiments

Payload elements included two commercial communications satellites, multiple mid-deck experiments, and technology demonstrations from organizations such as Hughes Aircraft Company, Telesat Canada, and academic teams at Massachusetts Institute of Technology and Stanford University. The mission manifest incorporated materials science investigations similar to earlier efforts on STS-3 and biomedical studies comparable to those on STS-9, with hardware provided by contractors including Rockwell International and payload integration by Marshall Space Flight Center and Kennedy Space Center teams.

Satellite retrieval and EVA operations

Mission objectives centered on the retrieval of two malfunctioning satellites deployed on an earlier mission: crews executed rendezvous, close stationkeeping, and capture operations influenced by techniques developed during Gemini Program proximity operations and tested in simulations at Johnson Space Center neutral buoyancy facilities. Extravehicular activities used tools and procedures refined from STS-41-B and required coordination with robotic support from the Canadarm built by Spar Aerospace and managed by Marshall Space Flight Center engineers. EVA crew members performed capture maneuvers, installed crew-applied grappling devices, and secured satellites for stowage in the payload bay, demonstrating capabilities subsequently referenced by Intelsat and Hughes Communications.

Flight timeline and mission events

After liftoff from Kennedy Space Center, the orbiter executed phasing burns overseen by flight controllers at Mission Control Center (Houston), conducted deployments and retrievals in successive orbits, and completed onboard experiments managed by Johnson Space Center payload specialists. The retrieval sequence included a planned rendezvous, multiple thruster firings coordinated with guidance systems from Rockwell International, and hand-controlled operations by pilots with flight experience from United States Naval Test Pilot School. The mission concluded with deorbit preparations, entry interface over the continental United States, and landing at Kennedy Space Center Shuttle Landing Facility.

Vehicle and launch details

The orbiter Discovery launched atop an external tank and two Solid Rocket Boosters produced by Thiokol with main engines designed by Rocketdyne. Ground processing and rollout operations were supported by Rockwell International and conducted at Kennedy Space Center integration facilities; mission integration involved Lewis Research Center avionics checkouts and contingency planning with Johnson Space Center flight surgeons. Launch commit criteria and countdown management followed protocols established after programs like Skylab and were coordinated with range safety personnel from United States Air Force assets at Patrick Air Force Base.

Aftermath and legacy

The mission's successful satellite retrievals validated in-orbit servicing techniques used later by programs such as Hubble Space Telescope servicing missions and influenced commercial satellite operations at Intelsat and Telesat Canada. Data and procedures from the mission informed policy deliberations at National Aeronautics and Space Administration and procurement decisions involving contractors like McDonnell Douglas and Grumman Corporation, shaping training at Johnson Space Center and EVA practice at the Neutral Buoyancy Lab. The mission remains cited in histories of the Space Shuttle program and studies of satellite recovery and on-orbit servicing.

Category:Space Shuttle missions