STS-41-B

Infobox Space mission
mission_name = STS-41-B
insignia = Sts-41-b-patch.png shuttle = Challenger
launch_pad = 39-A
launch = February 3, 1984, 13:00:00 UTC
landing = February 11, 1984, 12:15:55 UTC
Kennedy Space Center
duration = 7d/23:15:55
altitude = 350 km
inclination = 28.5°
orbits = 128
distance = 5,329,150 km
crew_photo = STS-41-B crew.jpg
crew_caption = 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).
previous = STS-9
next = 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.

The new numbering system was designed to be more specific in that the first numeral stood for the fiscal year offset into the shuttle program, the "4" being 1984. The second numeral represented the launch site; 1 for KSC, and 2 for Vandenberg AFB, Calif. (the latter was never used). The letter represented the order of launch assignment, "B" was the second launch scheduled in that fiscal year. (Following the Challenger accident, NASA reestablished the original numerical numbering system. Thus the only numbers according to this scheme were 41, 51, and 61. The first flight following STS-51-L is STS-26. If the numbering scheme had been kept, then the fourth flight in FY 1997 would have been 171-D, for example.)

Crew

* Vance D. Brand (3) - Commander
* Robert L. Gibson (1) - Pilot
* Bruce McCandless II (1) - Mission Specialist
* Ronald E. McNair (1) - Mission Specialist
* Robert L. Stewart (1) - Mission SpecialistNumber in parentheses indicates number of spaceflights by each individual prior to and including this mission.

Mission parameters

*Mass:
**"Orbiter liftoff:" 113,527 kg
**"Orbiter landing:" 91,278 kg
**"Payload:" 15,362 kg
*Perigee: 307 km
*Apogee: 316 km
*Inclination: 28.5°
*Period: 90.8 min

pace walks

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

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

Mission highlights

The mission was the fourth flight of the "Challenger". Liftoff occurred at 8 a.m. EST, on February 3, 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 convert|320|ft|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 February 11, 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.

Mission insignia

The historical first flight of the MMU is depicted on the flight insignia. The ten stars symbolize the flight's numerical designation in the Space Transportation System's mission sequence, in this case the tenth mission.

ee also

* Space science
* Space shuttle
* List of space shuttle missions
* List of human spaceflights chronologically

External links

* [http://science.ksc.nasa.gov/shuttle/missions/41-b/mission-41-b.html NASA mission description]
* [http://science.ksc.nasa.gov/shuttle/missions/41-b/41-b-info.html Additional information]
* [http://www.nss.org/resources/library/shuttlevideos/shuttle10.htm STS-41B Video Highlights]