Editing Apollo 11 (section)

=== Pre-launch ===

[[File:69-HC-620 - SA506.jpg|thumb|upright=1.3|left|Saturn V SA-506, the rocket carrying the Apollo 11 spacecraft, moves out of the [[Vehicle Assembly Building]] towards [[Launch Complex 39]].]]

The ascent stage of [[Lunar Module Eagle|LM-5 ''Eagle'']] arrived at the [[Kennedy Space Center]] on January 8, 1969, followed by the descent stage four days later, and [[Command module Columbia|CSM-107 ''Columbia'']] on January 23.<ref name="Mission Overview">{{cite web |title=Apollo 11 Mission Overview |publisher=NASA |url=https://www.nasa.gov/mission_pages/apollo/missions/apollo11.html |first=Sarah |last=Loff |access-date=September 22, 2018 |date=April 17, 2015 |archive-date=February 9, 2018 |archive-url=https://web.archive.org/web/20180209204039/https://www.nasa.gov/mission_pages/apollo/missions/apollo11.html |url-status=live }}</ref> There were several differences between ''Eagle'' and Apollo 10's LM-4 ''Snoopy''; ''Eagle'' had a VHF radio antenna to facilitate communication with the astronauts during their EVA on the lunar surface; a lighter ascent engine; more thermal protection on the landing gear; and a package of scientific experiments known as the [[Early Apollo Scientific Experiments Package]] (EASEP). The only change in the configuration of the command module was the removal of some insulation from the forward hatch.{{sfn|Benson|Faherty|1978|p=472}}<ref>{{cite web |url=https://airandspace.si.edu/exhibitions/apollo-to-the-moon/online/science/scientific-experiments.cfm |title=Scientific Experiments |website=Smithsonian Air and Space Museum |access-date=September 22, 2018 |archive-date=October 24, 2020 |archive-url=https://web.archive.org/web/20201024085033/https://airandspace.si.edu/exhibitions/apollo-to-the-moon/online/science/scientific-experiments.cfm |url-status=live }}</ref> The CSM was mated on January 29, and moved from the [[Operations and Checkout Building]] to the [[Vehicle Assembly Building]] on April 14.<ref name="Mission Overview" />

The [[S-IVB]] third stage of Saturn V AS-506 had arrived on January 18, followed by the [[S-II]] second stage on February 6, [[S-IC]] first stage on February 20, and the [[Saturn V Instrument Unit]] on February 27. At 12:30 on May 20, the {{convert|5443|t|adj=on}} assembly departed the Vehicle Assembly Building atop the [[crawler-transporter]], bound for Launch Pad 39A, part of [[Launch Complex 39]], while Apollo 10 was still on its way to the Moon. A countdown test commenced on June 26, and concluded on July 2. The launch complex was floodlit on the night of July 15, when the crawler-transporter carried the [[service structure|mobile service structure]] back to its parking area.<ref name="Mission Overview" /> In the early hours of the morning, the fuel tanks of the S-II and S-IVB stages were filled with [[liquid hydrogen]].{{sfn|Benson|Faherty|1978|p=474}} Fueling was completed by three hours before launch.{{sfn|Benson|Faherty|1978|p=475}} Launch operations were partly automated, with 43 programs written in the [[ATOLL (programming language)|ATOLL programming language]].{{sfn|Benson|Faherty|1978|pp=355–356}}

Slayton roused the crew shortly after 04:00, and they showered, shaved, and had the traditional pre-flight breakfast of steak and eggs with Slayton and the backup crew. They then donned their space suits and began breathing pure oxygen. At 06:30, they headed out to Launch Complex 39.{{sfn|Collins|2001|pp=355–357}} Haise entered ''Columbia'' about three hours and ten minutes before launch time. Along with a technician, he helped Armstrong into the left-hand couch at 06:54. Five minutes later, Collins joined him, taking up his position on the right-hand couch. Finally, Aldrin entered, taking the center couch.{{sfn|Benson|Faherty|1978|p=475}} Haise left around two hours and ten minutes before launch.<ref name="AP11FJ">{{cite web|url=https://history.nasa.gov/afj/ap11fj/01launch.html|title=Day 1, Part 1: Launch|via=NASA|access-date=October 11, 2018|publisher=Apollo Flight Journal|last1=Woods|first1=W. David|last2=MacTaggart|first2=Kenneth D.|last3=O'Brien|first3=Frank|date=June 6, 2019|archive-date=December 5, 2020|archive-url=https://web.archive.org/web/20201205085922/https://history.nasa.gov/afj/ap11fj/01launch.html|url-status=live}}</ref> The closeout crew sealed the hatch, and the cabin was purged and pressurized. The closeout crew then left the launch complex about an hour before launch time. The countdown became automated at three minutes and twenty seconds before launch time.{{sfn|Benson|Faherty|1978|p=475}} Over 450 personnel were at the consoles in the [[firing room]].{{sfn|Benson|Faherty|1978|p=474}}