Pressurized Mating Adapter
![]() PMA-2 attached to the forward port ofDestiny,where it was located between 2001 and 2007 | |
Module statistics | |
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Part of | International Space Station |
Launch date |
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Launch vehicle | Space Shuttle |
Docked |
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APressurized Mating Adapter(PMA) is a component used on theInternational Space Station(ISS) to convert theCommon Berthing Mechanism(CBM) interface used to connect ISS modules to anAPAS-95spacecraft docking port. Three PMAs are attached to theUS Orbital Segmentof ISS. PMA-1 and PMA-2 were launched along with theUnitymodule in 1998 aboardSTS-88;PMA-3 was launched in 2000 aboardSTS-92.PMA-1 permanently connects theUnityandZaryamodules.International Docking Adapterswere permanently installed on PMA-2 and PMA-3 in 2017 to convert them from the APAS-95 standard to the newerInternational Docking System Standard(IDSS).
Design and history
[edit]Its origins lie in designs for the Pressurized Docking Mast,[1]consisting of an off-axis frustoconical docking tunnel contained within a framework and a retractable coupling mechanism, later part of the Pressurized Berthing Adapter assembly that appeared in designs forSpace Station Freedom1987, and the reduced design referred to as 'Fred'[2]1991.
After 1992–1993 and the Russian integration into the International Space Station Alpha project,[3][4]this NASA docking design abruptly disappeared from all concepts.[5]This was due to the availability of Russian docking hardware and experience, brought together during theShuttle–Mir program.[6]RussianAPASdocking technology originally planned for the then defunct Soviet space shuttle program was integrated into the USSpace ShuttleODS (Orbital/Orbiter Docking System).[7]This could hard dock with the space station through a structural interface, which became the PMA.[8]With both the Russian docking ring and the CBM integrated into the PMA, this became the link between the USOS and the ROS from 1993.
Fabrication completed in 1995 with tests and mating tests with Node STA throughout 1996–97.[9]
![](https://upload.wikimedia.org/wikipedia/commons/thumb/7/7d/Ssfprg91.gif/220px-Ssfprg91.gif)
Uses
[edit]![](https://upload.wikimedia.org/wikipedia/commons/thumb/a/a3/ISS-59_Anne_McClain_with_an_electronic_tablet_inside_PMA-1.jpg/220px-ISS-59_Anne_McClain_with_an_electronic_tablet_inside_PMA-1.jpg)
The three PMAs are identical,[10]but they have slightly different uses. All three perform the same basic function of connecting aCBMport of an ISS module to anAPAS-95docking port of another module or visiting spacecraft.[11]For this purpose, the PMAs carry a passive CBM port and a passive APAS port. The PMAs are pressurized and heated from the inside, and they allow for power and data communications transfer through docking rings and external connections.[12]
PMA-1
[edit]This was one of the first components of the ISS (International Space Station). PMA-1 joins the Russian side of the station with the US side. OnSTS-88,the crew used the shuttle'srobotic armto attach theZaryacontrol module to PMA-1, which was already connected to the aft berthing port ofUnity.These first two station components are permanently connected by PMA-1.
PMA-2
[edit]![](https://upload.wikimedia.org/wikipedia/commons/thumb/a/aa/IDA_planned_locations_on_ISS.png/220px-IDA_planned_locations_on_ISS.png)
PMA-2 is mounted on the forward port of theHarmonyconnecting node, and was used whenSpace Shuttleorbiters docked at the ISS. It was outfitted withStation-to-Shuttle Power Transfer System(SSPTS) hardware to allow the shuttles to stay docked longer to the space station.[13]
PMA-2 was moved several times as part of thespace station assemblyprocess. It was originally connected to the forward hatch ofUnity,but whenSTS-98delivered theDestinymodule in February 2001, PMA-2 was moved to the berthing ring of theZ1 trussso thatDestinycould be berthed to the forward hatch ofUnity.PMA-2 was then moved to the forward hatch ofDestiny.[14](The removal of PMA-2 fromUnitywas the first time the CBM had been used to disconnect two ISS components.)[15]AfterSTS-120had deliveredHarmonyto the space station in October 2007,Canadarm2repositioned PMA-2 at the forward port ofHarmonyon November 12, 2007. Two days later, the combined package ofHarmonyand PMA-2 was moved to its final location, the forward hatch ofDestiny.On July 18, 2016,International Docking Adapter-2 was launched onSpaceX CRS-9.[16]It was attached and permanently connected to the APAS-95 port of PMA-2 during a spacewalk on August 19, 2016.[17]As of 2020, PMA-2 is expected to stay berthed at the forward port ofHarmonywith the IDA connected for the remaining duration of the ISS.
When a shuttle docked with the station, its "final approach [was] at a relative velocity of one-tenth of a foot per second. [As it made] contact with Pressurized Mating Adapter 2 [latches] automatically attached the two spacecraft together. Once relative motion between the spacecraft stopped, [a Shuttle astronaut retracted] the docking ring on [the Shuttle's] mechanism, closing latches to firmly secure the shuttle to the station."[18]
PMA-3
[edit]PMA-3 was brought to the ISS bySTS-92in October 2000, mounted on aSpacelabpallet.[19]It was initially attached to thenadir(bottom, or Earth-facing) hatch ofUnity.About six weeks later, whenSTS-97delivered theP6solar array truss structure,Endeavourdocked at PMA-3.[20]WhenSTS-98moved PMA-2 fromUnitytoDestinyvia the Z1 truss in February 2001,Atlantiswas docked at PMA-3.[14]For the remainder of the shuttle's operation, PMA-3 was not used for shuttle dockings. PMA-3 was moved in March 2001 toUnity's port hatch by the crew ofSTS-102to make room for the docking of aMulti-Purpose Logistics Module(MPLM).[21]
On August 30, 2007, PMA-3 was returned to the nadir port ofUnityto make room for the temporary docking of theHarmony (Node 2)module that was delivered bySTS-120.[22]Harmonywas transferred to the forward port ofDestiny,while PMA-3 was moved back to the port berthing mechanism ofUnityon August 7, 2009, to accommodate reconfiguration of theUnityport bulkhead by crew members in a pressurized environment.[23]On January 25, 2010, PMA-3 was moved from the port berthing mechanism ofUnityto the zenith (space-facing) port ofHarmonyto make room for theTranquility (Node 3)module which was added to the station duringSTS-130.After activation ofTranquility,PMA-3 was moved again on February 16, 2010, to the port location onTranquilitywhere theCupolaobservatory module had been docked for launch.[24]
PMA-3 was robotically removed fromTranquilityon March 26, 2017, and attached toHarmonyafter being prepared during a successfulspacewalk on March 24, 2017.A second spacewalk was conducted on March 30, 2017, to finalize the PMA-3 cable connections onHarmony.PMA-3 received International Docking Adapter-3 in August 2019.[25]
References
[edit]- ^"NASA had a docking mechanism design".
- ^"Space Station Fred".Archived fromthe originalon August 20, 2016.
- ^"BBC News | ISS | ISS timeline".
- ^"Space Station Options 1993".1993. Archived fromthe originalon August 20, 2016.
- ^"NASA began procuring Russian hardware and abandoned its formal docking mechanism design work".January 22, 2013.
- ^"Space Station: Update on the Impact of the Expanded Russian Role".July 29, 1994.
- ^"NASA adapted it and used the ODS for successful linkups with the Mir space station".2016.
- ^"docking node, was built in America but based in part on a Russian design".March 30, 1997.
- ^Zipay, John; Bernstein, Karen; Patin, Raymond; Bruno, Erica; Deloo, Phillipe (2012)."Structural Verification of the First Orbital Wonder of the World - the Structural Testing and Analysis of the International Space Station (ISS)".53rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference. 20th AIAA/ASME/AHS Adaptive Structures Conference. 14th AIAA.doi:10.2514/6.2012-1772.hdl:2060/20110013394.ISBN978-1-60086-937-2.
- ^Nasa.gov – Elements
- ^"Human Space Flight – Space Fact".NASA. July 4, 2002. Archived fromthe originalon September 25, 2002.RetrievedJanuary 17,2007.
- ^"STS-92 Press Release Kit: Payload section".NASA. October 10, 2000.RetrievedOctober 27,2007.
- ^"International Space Station Status Report #07-08".NASA.
- ^abSTS-98, Mission Control Center (February 10, 2001)."Status Report # 07".NASA.RetrievedJanuary 18,2007.
{{cite web}}
:CS1 maint: numeric names: authors list (link) - ^Harwood, William (February 10, 2001)."Atlantis crew to attach Destiny lab to station today".Spaceflight Now.RetrievedJanuary 15,2007.
- ^Jason Rhian (July 18, 2016)."SpaceX Conducts Second Ground Landing After Launch Of CRS-9 Dragon To ISS".Spaceflight Insider.
- ^Harwood, William (August 19, 2016)."Spacewalkers attach docking adapter to space station for commercial vehicles".Spaceflight.RetrievedAugust 20,2016.
- ^STS-102, Mission Control Center (March 9, 2001)."Status Report # 03".NASA.RetrievedJanuary 18,2007.
{{cite web}}
:CS1 maint: numeric names: authors list (link) - ^STS-92, Mission Control Center (October 16, 2000)."Status Report # 10".NASA.RetrievedJanuary 18,2007.
{{cite web}}
:CS1 maint: numeric names: authors list (link) - ^STS-97, Mission Control Center (December 2, 2000)."Status Report # 05".NASA.RetrievedJanuary 18,2007.
{{cite web}}
:CS1 maint: numeric names: authors list (link) - ^STS-102, Mission Control Center (March 11, 2001)."Status Report # 07".NASA.RetrievedJanuary 18,2007.
{{cite web}}
:CS1 maint: numeric names: authors list (link) - ^"SHUTTLE/SOYUZ/ISS PROCESSING MILESTONES".CBS News.
- ^"NASA - 08-07-2009 ISS On-Orbit Status".nasa.gov.RetrievedJune 3,2017.
- ^STS-130, Mission Control Center (February 16, 2010)."Status Report # 17".NASA.RetrievedFebruary 16,2010.
{{cite web}}
:CS1 maint: numeric names: authors list (link) - ^Pietrobon, Steven (August 20, 2018)."United States Commercial ELV Launch Manifest".RetrievedAugust 21,2018.
External links
[edit]![](https://upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/30px-Commons-logo.svg.png)
- YouTube animationCanadarm2 and Dextre move the PMA-3 between locations, one of the five times it was moved so that modules could use a Common Berthing Mechanism port instead of PMA-3.