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STS-41-B
Mission insignia
Mission statistics
Mission name	STS-41-B
Space shuttle	Challenger
Launch pad	39-A
Launch date	3 February 1984, 13:00:00 UTC
Landing	11 February 1984, 12:15:55 UTC Kennedy Space Center
Mission duration	7d/23:15:55
Number of orbits	128
Orbital altitude	189 nautical miles (350 km)
Orbital inclination	28.5°
Distance traveled	3,311,380 miles (5,329,150 km)
Crew photo
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).
Related missions
Previous mission Subsequent mission STS-9 STS-41-C

STS-41-B was the tenth space shuttle mission, and the fourth flight for Challenger. Following STS-9, the flight numbering system for Space Shuttle missions was changed. Thus, the next flight, instead of being designated STS-11, became STS 41-B. STS-10 was cancelled due to payload delays.

Crew

Mission parameters

• Mass:
  • Orbiter liftoff: 250,452 pounds (113,603 kg)
  • Orbiter landing: 201,238 pounds (91,280 kg)
  • Payload: 49,214 pounds (22,323 kg)
• Perigee: 166 nautical miles (307 km)
• Apogee: 171 nautical miles (317 km)
• Inclination: 28.5°
• Period: 90.8 min

Space walks

• McCandless and Stewart - EVA 1
• EVA 1 Start: 7 February 1984
• EVA 1 End: 7 February 1984
• Duration: 5 hours, 55 minutes

• McCandless and Stewart - EVA 2
• EVA 2 Start: 9 February 1984
• EVA 2 End: February 9, 1984
• Duration: 6 hours, 17 minutes

Mission highlights

Palapa B-2 after deployment.

Astronaut Bruce McCandless exercises the Manned Maneuvering Unit.

Bruce McCandless demonstrates the MMU floating in space above a clouded Earth.

McCandless approaches his maximum distance from Challenger.

The mission was the fourth flight of the Challenger. Liftoff occurred at 8 a.m. EST, on 3 February 1984. Two communications satellites were deployed about 8 hours after launch. One was for Western Union (WESTAR) and the other for Indonesia (Palapa B-2). However, the Payload Assist Modules (PAM) for both satellites malfunctioned placing them into a lower than planned orbit. Both satellites were retrieved successfully the following November during STS-51-A, the 14th mission, 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.

A highlight of the mission took place on the fourth day when astronauts McCandless and Stewart performed the first untethered space walk operating the Manned Maneuvering Unit (MMU) for the first time. McCandless, the first human Earth-orbiting satellite, 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. The seventh day of the mission, both astronauts performed an EVA to practice capture procedures for the Solar Maximum Mission satellite retrieval and repair operation planned for the next mission, STS-41-C.

Another important "first" for STS 41-B was the reflight of the West German-sponsored SPAS-l pallet/satellite originally flown on STS-7. This time, however, it remained in the payload bay because of 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 continuation of the Continuous Flow Electrophoresis System and the Monodisperse Latex Reactor experiments.

This flight marked the first untethered space walks by McCandless and Stewart, using the manned maneuvering unit. WESTAR-VI and PALAPA-B2 satellites deployed, unsuccessfully because the Payload Assist Module-D (PAM-D) rocket motors failed, leaving them in radical low-Earth orbits. The German-built Shuttle Pallet Satellite (SPAS), first flown on STS-7, became the first satellite to be refurbished and flown again. SPAS remained in the payload bay since there was an electrical problem with the Remote Manipulator System (RMS). This flight marked the first use of the RMS manipulator foot restraint and offered astronauts an opportunity to practice procedures for the Solar Maximum satellite retrieval and repair conducted on STS-41-C. An internal failure scrubbed the Integrated Rendezvous Target (IRT) exercise. Five Get Away Special canisters flew in the cargo bay and the crew used a Cinema-360 camera to document their flight. Other payloads: Acoustic Containerless Experiment System (ACES); Monodisperse Latex Reactor (MLR); and Radiation Monitoring Equipment (RME), and Isoelectric Focusing (IEF) payload.

The 7-day, 23-hour, 15-minute, 55-second flight ended on 11 February 1984, at 7:15 a.m. EST; at KSC's Shuttle Landing Facility -- the first landing of a spacecraft at its launch site. Challenger completed 127 orbits and traveled 2.8 million miles.

Wake-up calls

NASA began a tradition of playing music to astronauts during the Gemini program, which was first used to wake up a flight crew during Apollo 15. Each track is specially chosen, often by their families, and usually has a special meaning to an individual member of the crew, or is applicable to their daily activities.^[1]

See also

• Space science
• Space shuttle
• List of space shuttle missions
• List of spacewalks and moonwalks
• List of human spaceflights chronologically

References

External links

• NASA mission description
• Additional information
• STS-41B Video Highlights