Editing Service structure

{{short description|Structure built on a rocket launch pad to service launch vehicles}}
[[File:STS-114 rollout.jpg|thumb|{{OV|103}} is carried by a [[Crawler-transporter]], a launch tower is visible in the background]]
A '''service structure''' is a permanent [[steel]] [[Scaffolding|framework]] or [[tower]] erected on a [[rocket]] [[launch pad]] that allows assembly, servicing, and crew onboarding of the [[launch vehicle]] prior to [[Space launch|liftoff]]. 

In [[NASA]] [[Space launch|launches]] at the [[Kennedy Space Center]], [[astronauts]] enter the vehicle through a type of service structure called an  "[[Umbilical cable|umbilical]] tower". Immediately before ignition of the rocket's [[Rocket engine|engines]], all connections between the tower and the craft are severed, and the connecting [[Bridge|bridges]] swing away to prevent damage to structure and vehicle. An [[elevator]] in the tower also allows maintenance crew to service the vehicle. {{Citation needed|date=October 2021}}

==Kennedy Space Center==
During the NASA [[Space Shuttle program]], the structures at the [[Launch Complex 39]] pads contained a two-piece access tower system, the Fixed Service Structure (FSS) and the Rotating Service Structure (RSS). The FSS permitted access to the Shuttle via a retractable arm and a "beanie cap" to capture vented [[liquid oxygen]] (LOX) from the [[external fuel tank]]. The RSS contained the [[Payload]] Changeout Room, which offered "clean" access to the [[orbiter's]] payload bay, protection from the elements, and protection in winds up to {{convert|60|kn|km/h}}.{{Citation needed|date=October 2021}}

The FSS on Pad 39A was repurposed the top of the umbilical tower of [[Mobile Launcher]] 2, while the FSS on 39B re-used the umbilical tower of Mobile Launcher 3. Mobile Launcher 3 would later become Mobile Launcher Platform 1 for the Shuttle. {{Citation needed|date=March 2025}}

In 2011 NASA removed both the FSS and RSS from LC-39B to make way for a [[Artemis program|new generation of launch vehicles]]. In 2017-2018 [[SpaceX]] removed the RSS from [[LC-39A]] and modified the FSS for its [[SpaceX launch vehicles|new series of launch vehicles]].{{Citation needed|date=October 2021}}

Certain rockets such as the [[Delta (rocket family)|Delta]] and the [[Saturn V]] use structures consisting of a fixed portion and a mobile portion; the former is the umbilical tower and the latter is known as the "mobile service tower" or "mobile service structure," but often referred to as a ''[[wikt:gantry|gantry]]''. This mobile structure is moved away from the vehicle several hours before launch.

=== White room ===
[[File:STS white room.jpg|thumb|Closeout crew members help astronaut [[Andrew Feustel]] in the  [[Launch Complex 39]] white room prior to launch of [[STS-125]]]]
The '''white room''' was the small area used by [[astronauts]] to access the spacecraft during human flights up through the [[Space Shuttle program]].  The room takes its name from its white paint, which was used in [[Project Gemini]].  The room was first used in [[Project Mercury]]. Its use and white color (since Gemini) continued through subsequent programs of Apollo and the Space Shuttle.<ref>https://www.nasa.gov/blogs/spacestation/2024/03/03/all-aboard-astronauts-climb-into-dragon-endeavour/</ref>

Astronauts and closeout crew made their final preparations before liftoff, such as donning [[parachute]] packs, putting on [[spacesuit]] helmets, and detaching portable [[air-conditioning]] units.<ref>{{cite book|last=Burgess|first=Colin |title=Fallen astronauts: heroes who died reaching for the moon|year=2003|publisher=Bison Books|isbn=0-8032-6212-4}}</ref>
In 2014, NASA planned to move the White Room to a museum.<ref name=cs20140414>{{cite news |title=NASA signs over historic Launch Pad 39A to SpaceX |url=http://www.collectspace.com/news/news-041414a-launch-pad-39a-spacex.html |newspaper=collectSpace |date=2014-04-14 |access-date=2021-10-01 |archive-date=2014-08-24 |archive-url=https://web.archive.org/web/20140824060434/http://collectspace.com/news/news-041414a-launch-pad-39a-spacex.html |url-status=live }}</ref> SpaceX launches use a rotating "Crew Access Arm" for . {{Citation needed|date=March 2025}} As of the 2020 [[Crew Dragon Demo-2]] mission, SpaceX began calling the equivalent area of its Crew Access Arm at LC-39A the "White Room" in recognition of the original NASA structure's significance.<ref> https://www.nasa.gov/blogs/commercialcrew/2025/03/14/nasas-spacex-crew-10-arrives-at-launch-complex-39a-2/ </ref> On the first launch attempt, NASA and SpaceX flight crew began signing their respective "meatball" [[NASA insignia]] or SpaceX logos at the end of the Crew Access Arm, a practice which has become a tradition.{{Citation needed|date=December 2022}}

==Baikonur Cosmodrome==
Similarly, Soviet-and Russian-designed service structures such as those at [[Baikonur Cosmodrome]] [[Baikonur Cosmodrome Site 31|Site 31]] feature rotating crane-like "tower arms" that stand upright to service and secure the vehicle. The tower arms then pivot outward away from the rocket at launch.<ref> https://blogs.esa.int/eolaunches/2012/09/14/metop-on-the-launch-pad/ </ref>

==References==
{{reflist}}

{{Kennedy Space Center}}
{{Apollo program hardware}}
{{Space Shuttle}}

[[Category:Rocket launch technologies]]
[[Category:Apollo program hardware]]
[[Category:Space Shuttle program]]