View source for STS-51-A

{{Short description|1984 American crewed spaceflight to deploy and retrieve communications satellites}}
{{Use American English|date=January 2022}}
{{Use mdy dates|date=October 2022}}
{{Infobox spaceflight
| name               = STS-51-A
| names_list         = [[Space Transportation System]]-14
| image              = Satellites For Sale - GPN-2000-001036.jpg
| image_caption      = [[Dale Gardner|Dale A. Gardner]] poses in front of a camera with a "For Sale" sign in his hand, jokingly referring to the two broken satellites ([[Palapa]] B2 and [[Westar]] 6) the crew was sent out on EVA to pick up and return to [[Earth]].
| mission_type       = [[Communications satellite]]s deployment<br />Communications satellites retrieval
| operator           = [[NASA]]
| mission_duration   = {{time interval|November 8, 1984, 12:15:00|November 16, 1984, 11:59:56|show=dhms|sep=,}}
| distance_travelled = {{cvt|5293786|km}}
| orbits_completed   = 127
| spacecraft         = {{OV|103}}
| launch_mass        = {{cvt|119442|kg}}
| landing_mass       = {{cvt|94123|kg}}
| payload_mass       = {{cvt|17375|kg}}
| crew_size          = 5
| crew_members       = {{Unbulleted list|[[Frederick Hauck|Frederick H. Hauck]]|[[David M. Walker (astronaut)|David M. Walker]]|[[Joseph P. Allen]]|[[Anna Lee Fisher]]|[[Dale Gardner|Dale A. Gardner]]}}
| crew_EVAs          = 2
| crew_EVA_duration  = {{Unbulleted list
| 11{{nbsp}}hours, 42{{nbsp}}minutes
| {{Small|1st{{nbsp}}EVA: 6{{nbsp}}hours}}
| {{Small|2nd{{nbsp}}EVA: 5{{nbsp}}hours, 42{{nbsp}}minutes}}
}}
| launch_date        = {{Start date|November 8, 1984, 12:15:00|timezone=yes}}{{nbsp}}[[Coordinated Universal Time|UTC]] (7:15{{nbsp}}am{{nbsp}}[[Eastern Standard Time|EST]])
| launch_site        = [[Kennedy Space Center|Kennedy]], [[Kennedy Space Center Launch Complex 39A|LC-39A]]
| launch_contractor  = [[Rockwell International]]
| landing_date       = {{End date|November 16, 1984, 11:59:56|timezone=yes}}{{nbsp}}UTC (6:59:56{{nbsp}}am{{nbsp}}EST)
| landing_site       = Kennedy, [[Shuttle Landing Facility|SLF&nbsp;Runway&nbsp;15]]
| orbit_reference    = [[Geocentric orbit]]<ref name=satcat>{{cite web|title=SATCAT|url=http://planet4589.org/space/log/satcat.txt|publisher=Jonathan's Space Report|access-date=March 23, 2014}}</ref>
| orbit_regime       = [[Low Earth orbit]]
| orbit_periapsis    = {{cvt|332|km}}
| orbit_apoapsis     = {{cvt|354|km}}
| orbit_inclination  = 28.45°
| orbit_period       = 90.40 minutes
| apsis              = gee
| instruments        = Diffused Mixing of Organic Solutions (DMOS)
| insignia           = Sts-51-a-patch.png
| insignia_caption   = STS-51-A mission patch
| crew_photo         = STS-51-A crew.jpg
| crew_photo_caption = From left: [[Dale Gardner|Gardner]], [[David M. Walker (astronaut)|Walker]], [[Anna Lee Fisher|Fisher]], [[Frederick Hauck|Hauck]] and [[Joseph P. Allen|Allen]]
| programme          = [[Space Shuttle program]]
| previous_mission   = [[STS-41-G]] (13)
| next_mission       = [[STS-51-C]] (15)
}}
'''STS-51-A''' (formerly STS-19) was the 14th flight of [[NASA]]'s [[Space Shuttle program]], and the second flight of [[Space Shuttle Discovery|Space Shuttle ''Discovery'']]. The mission launched from [[Kennedy Space Center]] on November 8, 1984, and landed just under eight days later on November 16, 1984.
STS-51-A marked the first time a shuttle deployed two [[communications satellite]]s, and retrieved from orbit two other communications satellites. The Canadian [[Anik (satellite)|Anik D2]] and [[Syncom]] IV-1 satellites were both successfully deployed by the crew of ''Discovery''. [[Palapa]] B2 and [[Westar]] 6, meanwhile, had been deployed during the [[STS-41-B]] mission earlier in the year, but had been placed into improper orbits due to the malfunctioning of their [[Apogee kick motor|kick motors]]; they were both safely recovered and returned to [[Earth]] during STS-51-A.
== Crew ==
{{Spaceflight crew
| terminology = Astronaut
| position1   = Commander
| crew1_up    = [[Frederick Hauck|Frederick H. Hauck]]
| flights1_up = Second
| position2   = Pilot
| crew2_up    = [[David M. Walker (astronaut)|David M. Walker]]
| flights2_up = First
| position3   = Mission Specialist 1
| crew3_up    = [[Joseph P. Allen]]
| flights3_up = Second and last
| position4   = Mission Specialist 2<br />Flight Engineer
| crew4_up    = [[Anna Lee Fisher]]
| flights4_up = Only
| position5   = Mission Specialist 3
| crew5_up    = [[Dale Gardner|Dale A. Gardner]]
| flights5_up = Second and last
}}
=== Spacewalks ===
;EVA 1
* '''Personnel''': Allen and Gardner
* '''Date''': November 12, 1984 (13:25–19:25 UTC)
* '''Duration''': 6{{nbsp}}hours
;EVA 2
* '''Personnel''': Allen and Gardner
* '''Date''': November 14, 1984 (11:09–16:51 UTC)
* '''Duration''': 5{{nbsp}}hours, 42{{nbsp}}minutes
=== Crew seat assignments ===
{| class="wikitable" style="text-align:center"
! Seat<ref>{{cite web|title=STS-51A|url=http://spacefacts.de/mission/english/sts-51a.htm|publisher=Spacefacts|access-date=February 26, 2014}}</ref>
! Launch
! Landing
|rowspan=8| [[File:Space Shuttle seating plan.svg|150px]]<br />Seats 1–4 are on the flight deck.<br />Seats 5–7 are on the mid-deck.
|-
! 1
|colspan=2| Hauck
|-
! 2
|colspan=2| Walker
|-
! 3
| Allen
| Gardner
|-
! 4
|colspan=2| Fisher
|-
! 5
| Gardner
| Allen
|-
! 6
|colspan=2 style="background-color:lightgray"| ''Unused''
|-
! 7
|colspan=2 style="background-color:lightgray"| ''Unused''
|}
== Mission summary ==
{{LaunchAttempt
| date1           = 1984-11-07 8:23
| result1         = Scrubbed
| reason1         = Weather
| decision_date1  = 1984-11-07 7:51
| decision_clock1 = −00:20:00 hold
| notes1          = High windshear in the KSC area.<ref>{{Cite news |date=1984-11-07 |title=Stiff, erratic crosswinds postpone liftoff of Discovery, 5 astronauts |url=https://news.google.com/newspapers?nid=Aul-kAQHnToC&dat=19841107&printsec=frontpage&hl=en |access-date=2024-11-29 |work=Deseret News |via=Google News}}</ref>
| date2           = 1984-11-08 7:15
| result2         = Success
}}
STS-51-A was launched from [[Florida]]'s Kennedy Space Center (KSC) at 7:15:00 a.m. [[Eastern Time Zone|EST]], on November 8, 1984, less than a month after the [[STS-41-G]] flight. A launch attempt the day before was scrubbed at T-minus 20 minutes due to high [[Wind gradient|shear winds]] in the [[upper atmosphere]].
The five-person flight crew consisted of Frederick H. Hauck, commander, on his second flight; pilot David M. Walker; and three mission specialists – Anna Lee Fisher, Dale A. Gardner and Joseph P. Allen. Both Gardner and Allen were making their second shuttle flights. STS-51-A marked the first flight of the Space Shuttle commanded by an astronaut from the 1978 class rather than the [[Apollo program|Apollo era]].
The two communications satellites successfully deployed were [[Anik (satellite)|Anik D2]] (on the second day of the mission) and [[Syncom]] IV-1, also known as [[Syncom|Leasat 1]] (on the third day); both were Hughes-built satellites. The orbiter then began a series of maneuvers to meet up with the first of the two satellites to be recovered, Palapa B2. The orbits of both satellites had been lowered by ground commands from about {{cvt|970|km}} to {{cvt|340|km}} to facilitate recovery operations. On day five of the mission, ''Discovery'' rendezvoused with Palapa. Mission specialists Allen and Gardner performed an EVA, capturing the satellite with a device known as a "Stinger" (Apogee Capture Device (ACD)),<ref>{{cite journal|url=https://ntrs.nasa.gov/search.jsp?R=19870020429|title=AKM (Apogee Kick Motor) Capture Device (ACD) |journal=The 21st Aerospace Mechanisms Symposium|date=May 1, 1987|last1=Harwell|first1=William D.}}</ref> which was inserted into the satellite's [[Apogee kick motor|apogee motor nozzle]] by Allen. The satellite's rotation was slowed to 1 [[Revolutions per minute|RPM]], and Gardner, operating from a position on the end of the Remote Manipulator System (RMS) ([[Canadarm]]), attempted unsuccessfully to grapple the satellite. Allen was able to manually maneuver the satellite into its cradle with Gardner's help, further aided by the Canadarm, which was operated by Fisher. The successful, improvised rescue effort took two hours.
The recovery of Westar 6 was not as difficult, and took place a day later. This time, Gardner, using the same muscle-power technique Allen had used for Palapa B2's rescue, easily captured the satellite. With Allen's help, he placed it in a cradle in the cargo bay. Following Westar 6's recovery, Gardner humorously held up a "For Sale" sign, as if trying to find someone to sell the malfunctioning satellites to, as a means to indicate the successful recovery and as a means to provide some comical relief for the troubled owners. The Westar satellite was, ironically enough, indeed later sold to Hong Kong–based [[AsiaSat]].
The STS-51-A mission also carried the Diffused Mixing of Organic Solutions (DMOS) experiment. It was the first of a series of comprehensive organic and [[polymer]] science experiments sponsored by
[[3M]]. This mid-deck experiment was successful, and the proprietary results of the chemical mixes were turned over to 3M. One other experiment, a [[radiation monitoring]] experiment, was also performed.
The satellite recoveries on STS-51-A were the last [[Extravehicular activity|untethered spacewalks]] until 1994, and marked the last use of the [[Manned Maneuvering Unit]] (MMU). In 1994, the
[[Simplified Aid For EVA Rescue]] (SAFER) was tested on [[STS-64]]. On all subsequent spacewalks conducted by both NASA and the [[Soviet Union|Soviet]]/[[Russia]]n space agencies, the astronauts were tethered to the craft by some means.
The second mission of ''Discovery'' ended at 6:59:56 a.m. EST on November 16, 1984, with a successful landing on Runway 15 at KSC. Footage of the landing was used in opening scene of the 1985 [[IMAX]] movie ''[[The Dream is Alive]]''. The flight completed 127 orbits, and lasted 7 days, 23 hours, 44 minutes, and 56 seconds. It was the third shuttle landing at KSC, and the fifth and last shuttle mission of 1984.
== Mission insignia ==
STS-51-A Mission insignia depicts the Space Shuttle ''Discovery'' en route to Earth orbit for NASA's STS-51-A mission and is reminiscent of a soaring eagle, shown in the insignia. The red and white trailing stripes, the blue background, and the presence of the Eagle, generate memories of America's 208 year-old history and traditions. The two satellites orbiting the Earth backgrounded amidst a celestial scene are a universal representation of the versatility of the Space Shuttle. The two satellites it is meant to retrieve are also included as a more specific reference to the mission's main objective and a highlight of what part of the Shuttle's versatile mission capabilities she would be covering this time. White lettering against the blue border lists the surnames of the five-member crew.
== Wake-up calls ==
NASA began a tradition of playing music to astronauts during the [[Project Gemini]], 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.<ref name="chronology">{{cite news|first=Colin|last=Fries|title=Chronology of Wakeup Calls|date=June 25, 2007|publisher=NASA|url=https://history.nasa.gov/wakeup%20calls.pdf|access-date=August 13, 2007|archive-date=December 20, 2023|archive-url=https://web.archive.org/web/20231220093919/https://history.nasa.gov/wakeup%20calls.pdf|url-status=dead}} {{PD-notice}}</ref>
{| class="wikitable"
|-
! Flight Day
! Song
! Artist/Composer
|-
| Day 2
| "[[Marine Corps Hymn]]"
|
|-
| Day 3
| "Theme from ''[[For a Few Dollars More]]''"
| [[Ennio Morricone]]
|}
== Gallery ==
<gallery>
File:STS-51-A Syncom IV-1 deployment.jpg|Syncom IV-1 after deployment
File:STS-51-A Westar 6 retrieval.jpg|Dale Gardner retrieves Westar 6.
File:STS-51-A Palapa B-2 retrieval.jpg|Palapa B2 is loaded into the payload bay.
</gallery>
== See also ==
{{Portal|Spaceflight}}
* [[List of human spaceflights]]
* [[List of Space Shuttle missions]]
== References ==
{{Reflist|30em}}
== External links ==
* [http://science.ksc.nasa.gov/shuttle/missions/51-a/mission-51-a.html NASA mission summary] {{Webarchive|url=https://web.archive.org/web/20120716183330/http://science.ksc.nasa.gov/shuttle/missions/51-a/mission-51-a.html |date=July 16, 2012 }}
* [https://archive.org/details/PostMissionPressConferenceSpaceShuttleDiscoverySTS51ASTS14complete Video from post mission press conference with extensive footage available for download at www.archive.org The Internet Archive]
* [http://www.nss.org/resources/library/shuttlevideos/shuttle14.htm STS-51-A Video Highlights] {{Webarchive|url=https://web.archive.org/web/20120717225813/http://www.nss.org/resources/library/shuttlevideos/shuttle14.htm |date=July 17, 2012 }}
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{{Orbital launches in 1984}}
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[[Category:1984 in the United States]]
[[Category:Spacecraft launched in 1984]]
[[Category:Spacecraft which reentered in 1984]]