Editing Space Shuttle (section)

===Launch preparation===
{{see also|Launch commit criteria}}
[[File:Crawler transporter with Atlantis on the ramp to pad 39A.jpg|thumb|right|alt=The Space Shuttle moving to the launch complex on a crawler-transporter|The crawler-transporter with ''Atlantis'' on the ramp to LC-39A for [[STS-117]]]]

The Space Shuttle was prepared for launch primarily in the VAB at the KSC. The SRBs were assembled and attached to the external tank on the MLP. The orbiter vehicle was prepared at the [[Orbiter Processing Facility]] (OPF) and transferred to the VAB, where a crane was used to rotate it to the vertical orientation and mate it to the external tank.<ref name= shuttle_manual />{{rp|132–133}} Once the entire stack was assembled, the MLP was carried for {{convert|3.5|mi|km|sigfig=2|sp=us|order=flip|adj=off|abbr=on}} to [[Launch Complex 39]] by one of the [[crawler-transporter]]s.<ref name= shuttle_manual />{{rp|137}} After the Space Shuttle arrived at one of the two launchpads, it would connect to the Fixed and Rotation Service Structures, which provided servicing capabilities, payload insertion, and crew transportation.<ref name= shuttle_manual />{{rp|139–141}} The crew was transported to the launch pad at T−3&nbsp;hours and entered the orbiter vehicle, which was closed at T−2&nbsp;hours.<ref name=jenkins2016 />{{rp|III–8}} Liquid oxygen and hydrogen were loaded into the external tank via umbilicals that attached to the orbiter vehicle, which began at T−5&nbsp;hours&nbsp;35&nbsp;minutes. At T−3&nbsp;hours&nbsp;45&nbsp;minutes, the hydrogen fast-fill was complete, followed 15&nbsp;minutes later by the oxygen tank fill. Both tanks were slowly filled up until the launch as the oxygen and hydrogen evaporated.<ref name=jenkins2016 />{{rp|II–186}}

The [[launch commit criteria]] considered precipitation, temperatures, cloud cover, lightning forecast, wind, and humidity.<ref name="weather launch criteria">{{cite web |url=https://www.nasa.gov/centers/kennedy/news/releases/2003/release-20030128.html |last=Diller |first=George |author-link=George Diller |date=May 20, 1999 |url-status=dead |archive-url=https://web.archive.org/web/20200807074521/https://www.nasa.gov/centers/kennedy/news/releases/2003/release-20030128.html |title= Space Shuttle weather launch commit criteria and KSC end of mission weather landing criteria |access-date=May 1, 2020 |work=KSC Release No. 39-99 |publisher=NASA |department=[[Kennedy Space Center]] (KSC) |archive-date=August 7, 2020}}</ref> The Space Shuttle was not launched under conditions where it could have been struck by [[lightning]], as its exhaust plume could have triggered lightning by providing a current path to ground after launch, which occurred on [[Apollo 12#Mission highlights|Apollo&nbsp;12]].<ref name="chaikin">{{cite book |last=Chaikin |first=Andrew |author-link=Andrew Chaikin |title=A Man on the Moon: The Voyages of the Apollo Astronauts |publisher=[[Penguin Group]] |date=2007 |url=https://books.google.com/books?id=E043uAEACAAJ&q=a+man+on+the+moon |isbn=978-0-14-311235-8 |access-date=October 17, 2020 |archive-date=April 17, 2021 |archive-url=https://web.archive.org/web/20210417071628/https://books.google.com/books?id=E043uAEACAAJ&q=a+man+on+the+moon |url-status=live}}</ref>{{rp|239}} The NASA Anvil Rule for a Shuttle launch stated that an [[anvil cloud]] could not appear within a distance of {{convert|10|nmi|km|lk=in|order=flip|abbr=on}}.<ref name="anvil">{{cite web |last=Oblack |first=Rachelle |title=The Anvil Rule: How NASA Keeps Its Shuttles Safe form Thunderstorms |website=Thoughtco.com |date=March 5, 2018 |url=https://www.thoughtco.com/anvil-cloud-rule-3444263 |access-date=September 17, 2018 |archive-date=June 8, 2020 |archive-url=https://web.archive.org/web/20200608064339/https://www.thoughtco.com/anvil-cloud-rule-3444263 |url-status=live}}</ref> The Shuttle Launch Weather Officer monitored conditions until the final decision to scrub a launch was announced. In addition to the weather at the launch site, conditions had to be acceptable at one of the [[Space Shuttle abort modes#Transoceanic abort landing|Transatlantic Abort Landing sites]] and the SRB recovery area.<ref name="weather launch criteria" /><ref name="sts121_blog">{{cite web |title=NASA's Launch Blog – Mission STS-121 |publisher=NASA |date=July 1, 2006 |url=https://www.nasa.gov/mission_pages/shuttle/launch/sts-121/launch-vlcc_070106.html |access-date=May 1, 2020 |archive-date=May 24, 2017 |archive-url=https://web.archive.org/web/20170524123552/https://www.nasa.gov/mission_pages/shuttle/launch/sts-121/launch-vlcc_070106.html |url-status=live}}</ref>