STS-41B

STS-41B
NASA · Public domain · source
Mission	STS-41B
Spacecraft	Space Shuttle Challenger
Operator	National Aeronautics and Space Administration
Cospar id	1984-036A
Satcat	14723
Mission duration	7 days, 23 hours, 15 minutes, 28 seconds
Launch date	1984-02-03
Launch site	Kennedy Space Center Launch Complex 39A
Landing date	1984-02-11
Landing site	Edwards Air Force Base
Orbit	Low Earth orbit

STS-41B was the tenth mission of the Space Shuttle program and the second flight of the orbiter Challenger. Launched on 3 February 1984 from Kennedy Space Center and landed on 11 February 1984 at Edwards Air Force Base, the flight conducted satellite deployments, extravehicular activities, and testing of new maneuvering systems. The mission carried a seven-member crew drawn from NASA, United States Air Force, and allied institutions, and contributed to later developments in Space Shuttle program operations and Extravehicular activity techniques.

Mission overview

The mission launched from Kennedy Space Center Launch Complex 39A atop a Space Shuttle external tank with two Solid Rocket Boosters, following processing at the Vehicle Assembly Building and rollout across the Kennedy Space Center Redditch facilities. Primary objectives included deployment of two Westar 6 and Palapa B2 communications satellites built by Westinghouse Electric Corporation and Hughes Aircraft Company, demonstration of the Manned Maneuvering Unit developed by Martin Marietta, and a series of experiments managed by Marshall Space Flight Center, Johnson Space Center, and contractors such as Aeronutronic and McDonnell Douglas. The mission operated in Low Earth orbit with mission control coordination from Mission Control Center (Houston), and integrated payload operations with partners including Western Union and Indonesian Satellite Corporation (Perumtel).

Crew

The seven-person crew included commander Vance D. Brand, pilot Robert L. Gibson, mission specialists Bruce McCandless II, Ronald E. McNair, and Robert L. Stewart, plus mission specialists representing payload operations. Flight crew training involved facilities at Johnson Space Center, Cape Canaveral Air Force Station, and contractor sites such as Hughes Aircraft Company and Martin Marietta. Support personnel included representatives from NASA Flight Crew Directorate, Kennedy Space Center operations, and engineering groups from Rockwell International.

Payload and experiments

Payloads included the two commercial communications satellites Westar 6 (for Western Union) and Palapa B2 (for Perumtel), both intended for geostationary transfer via the orbiter-launched Inertial Upper Stage built by The Boeing Company and Martin Marietta. The middeck and payload bay hosted experiments from Marshall Space Flight Center and Johnson Space Center, such as materials processing investigations overseen by NASA Lewis Research Center and life-sciences tests coordinated with National Institutes of Health contractors. Technology demonstrations included the first operational flight test of the Manned Maneuvering Unit developed under contract with Martin Marietta and avionics evaluations involving Rockwell International subsystems.

EVA and satellite deployment

Two extravehicular activities featured astronaut Bruce McCandless II and Robert L. Stewart testing the Manned Maneuvering Unit in untethered flight while other crew conducted satellite deployment operations. Deployments of Westar 6 and Palapa B2 used the orbiter's payload bay and the Inertial Upper Stage; however, both satellites experienced failures to reach their intended geostationary orbits due to issues with the Inertial Upper Stage motor, prompting salvage attempts. The EVAs demonstrated free-flying maneuvering techniques previously developed for operations related to Skylab and Apollo program rendezvous, and informed subsequent Extravehicular activity procedures and safety protocols managed by Johnson Space Center EVA offices.

Flight timeline

After liftoff from Kennedy Space Center on 3 February 1984, Challenger achieved a stable Low Earth orbit and initiated payload bay operations coordinated with Mission Control Center (Houston). Satellite deployment events occurred on flight days two and three, involving separation sequences and planned ignition of the Inertial Upper Stage motors. Following reported anomalies during deployment, crew members executed additional onboard procedures while EVAs were conducted to test the Manned Maneuvering Unit capabilities and practice retrieval concepts that had been developed with input from Marshall Space Flight Center and contractors. The mission concluded with deorbit burn and entry over the Pacific Ocean and a runway landing at Edwards Air Force Base on 11 February 1984, after interactions with Dryden Flight Research Facility and NASA Flight Operations.

Mission aftermath and impact

Following return, investigations into the failed geostationary transfers involved teams from NASA, The Boeing Company, Martin Marietta, Hughes Aircraft Company, and international stakeholders like Western Union and Perumtel, leading to policy and engineering adjustments for subsequent Space Shuttle commercial deployments. The successful demonstration of the Manned Maneuvering Unit by Bruce McCandless II and Robert L. Stewart influenced later Extravehicular activity planning for missions including STS-6 and Hubble Space Telescope servicing preparations. Lessons learned from the mission affected procedures at Kennedy Space Center, Johnson Space Center, and contractor facilities such as Rockwell International and Martin Marietta, and contributed to debates in United States Congress and commercial satellite operators about the role of the Space Shuttle program in delivering payloads to geostationary orbit. Category:Space Shuttle missions