STS-41-B

STS-41-B

Bruce McCandless demonstrates the Manned Maneuvering Unit (MMU), floating in space above a clouded Earth.
Mission type	Satellite deployment Equipment testing
Operator	NASA
COSPAR ID	1984-011A
SATCAT №	14681
Mission duration	7 days, 23 hours, 15 minutes, 55 seconds
Distance travelled	5,329,150 kilometres (3,311,380 mi)
Orbits completed	128
Spacecraft properties
Spacecraft	Space Shuttle Challenger
Launch mass	113,603 kilograms (250,452 lb)
Landing mass	91,280 kilograms (201,238 lb)
Payload mass	12,815 kilograms (28,252 lb)
Crew
Crew size	5
Members	Vance D. Brand Robert L. Gibson Bruce McCandless II Robert L. Stewart Ronald E. McNair
EVAs	2
EVA duration	12 hours, 12 minutes First: 5 hours, 55 minutes Second: 6 hours, 17 minutes
Start of mission
Launch date	February 3, 1984, 13:00:00 (1984-02-03UTC13Z) UTC
Launch site	Kennedy LC-39A
End of mission
Landing date	February 11, 1984, 12:15:55 (1984-02-11UTC12:15:56Z) UTC
Landing site	Kennedy SLF Runway 15
Orbital parameters
Reference system	Geocentric
Regime	Low Earth
Perigee	307 kilometres (166 nmi)
Apogee	317 kilometres (171 nmi)
Inclination	28.5 degrees
Period	90.8 minutes
Epoch	February 5, 1984
L-R: Seated, Vance Brand, Commander, Robert Gibson, Pilot. Standing, L-R: Mission Specialists Robert L. Stewart, Ronald McNair and Bruce McCandless. Stewart and McCandless are wearing extravehicular mobility units (EMU). Space Shuttle program ← STS-9 STS-41-C →

STS-41-B was the tenth NASA Space Shuttle mission and the fourth flight of the Space Shuttle Challenger. It launched on February 3, 1984, and landed on February 11 after deploying two communications satellites. It was also notable for including the first untethered spacewalk.

Following STS-9, the flight numbering system for the Space Shuttle program was changed. Thus, the next flight, instead of being designated STS-11, became STS-41-B; the original successor to STS-9, STS-10, was cancelled due to payload delays.

Crew

Position	Astronaut
Commander	Vance D. Brand Third spaceflight
Pilot	Robert L. Gibson First spaceflight
Mission Specialist 1	Bruce McCandless II First spaceflight
Mission Specialist 2	Robert L. Stewart First spaceflight
Mission Specialist 3	Ronald E. McNair First spaceflight

Spacewalks

EVA 1

• Personnel: McCandless and Stewart
• Date: February 7, 1984
• Duration: 5 hours, 55 minutes

EVA 2

• Personnel: McCandless and Stewart
• Date: February 9, 1984
• Duration: 6 hours, 17 minutes

Crew seating arrangements

Seat	Launch	Landing	Seats 1–4 are on the Flight Deck. Seats 5–7 are on the Middeck.
S1	Brand	Brand
S2	Gibson	Gibson
S3	McNair	McCandless
S4	Stewart	Stewart
S5	McCandless	McNair

Mission summary

Palapa B2 after deployment. Astronaut Bruce McCandless exercises the Manned Maneuvering Unit. McCandless approaches his maximum distance from Challenger.

Challenger lifted off from Kennedy Space Center at 8 am EST on February 3, 1984. Two communications satellites were deployed about 8 hours after launch; one, Westar 6, was for America's Western Union, and the other, Palapa B2, for Indonesia. However, the Payload Assist Modules (PAM) for both satellites malfunctioned, placing them into a lower-than-planned orbit. Both satellites were retrieved successfully in November 1984 during STS-51-A, which was conducted by the orbiter Discovery.

The STS-41-B crew included commander Vance D. Brand, making his second Shuttle flight; pilot Robert L. Gibson; and mission specialists Bruce McCandless II, Ronald E. McNair, and Robert L. Stewart.

On the fourth day of the mission, astronauts McCandless and Stewart performed the first untethered spacewalk, operating the Manned Maneuvering Unit (MMU) for the first time. McCandless ventured out 320 feet (98 m) from the orbiter, while Stewart tested the "work station" foot restraint at the end of the Remote Manipulator System. On the seventh day of the mission, both astronauts performed another EVA to practice capture procedures for the Solar Maximum Mission satellite retrieval and repair operation, which was planned for the next mission, STS-41-C.

STS-41-B also achieved the reflight of the West German-sponsored SPAS-1 pallet/satellite, which had originally flown on STS-7. This time, however, it remained in the payload bay due to an electrical problem in the RMS. The mission also carried five GAS canisters, six live rats in the middeck area, a Cinema-360 camera and a continuation of the Continuous Flow Electrophoresis System and Monodisperse Latex Reactor experiments. Included in one of the GAS canisters was the first experiment by a high school team to fly in space. The experiment, on seed germination and growth in zero gravity, was created and built by a team from Brighton High School in Utah through a partnership with Utah State University.

The 7-day, 23-hour, 15-minute, 55-second flight ended on February 11, 1984 with a successful landing at Kennedy Space Center's Shuttle Landing Facility. This marked the first landing of a spacecraft at its launch site. Challenger completed 127 orbits and traveled 2.8 million miles.

Astronaut Ronald E. McNair would later die in the Challenger disaster on 28 January 1986.

Mission insignia

Designed by artist Robert McCall, the eleven stars in the blue field symbolize the mission's original designation as STS-11. The left panel shows the deployment of a satellite, and the right panel shows an astronaut using the MMU.

Wake-up calls

NASA began a tradition of playing music to astronauts during the Gemini program, and first used music to wake up a flight crew during Apollo 15. Each track is specially chosen, often by the astronauts' families, and usually has a special meaning to an individual member of the crew, or is applicable to their daily activities.

Day 3	"A Train"	Contraband
Day 4	"Glory, Glory, Colorado"	The University of Colorado Band	Vance Brand
Day 5	"Armed Forces Medley"
Day 7	"Theme from The Greatest American Hero"	Joey Scarbury
Day 8	"The Air Force Song"	Air Force CAPCOMs
Day 9	"In the Mood"	Contraband

See also

• List of human spaceflights
• List of Space Shuttle missions
• Lists of spacewalks and moonwalks

References

 This article incorporates public domain material from websites or documents of the National Aeronautics and Space Administration.

External links

• Mission summary and additional information. NASA.
• STS-41-B video highlights. NSS.