Editing AS-203 (section)

{{Short description|Uncrewed flight of the Saturn IB rocket, July 5, 1966}}
{{use mdy dates|date=September 2021}}
{{Infobox spaceflight
| name                  = AS-203
| image                 = Image:AS-203 launch.jpg
| image_caption         = Launch of AS-203
<!-- NO insignia for this mission; Apollo program insignia does not apply -->

| mission_type          = Launch vehicle development
| operator              = [[NASA]]
| COSPAR_ID             = 1966-059A 
| SATCAT                = 2289
| mission_duration      = ~6 hours 
| orbits_completed      = 4
| distance_travelled    = {{convert|87400|nmi|km|disp=flip|sp=us}}

| spacecraft            = None
| launch_mass           = <!--{{convert|58700|lb|kg|disp=flip}} This is incorrect and needs verification; also the term "launch mass" is misleading and irrelevant since the payload was the upper stage plus unspent fuel-->

| launch_date           = {{start date text|July 5, 1966, 14:53:13|timezone=yes}}&nbsp;UTC 
| launch_rocket         = [[Saturn IB]] SA-203
| launch_site           = [[Cape Canaveral Air Force Station|Cape Kennedy]] [[Cape Canaveral Air Force Station Space Launch Complex 37|LC-37B]]
| destroyed             = {{end date text|July 5, 1966}}

| orbit_epoch           = July 5, 1966<ref name=satcat>{{cite web|last=McDowell|first=Jonathan|title=SATCAT|url=http://planet4589.org/space/log/satcat.txt|publisher=Jonathan's Space Pages|access-date=March 23, 2014}}</ref>

| orbit_reference       = [[geocentric orbit|Geocentric]]
| orbit_regime          = [[Low Earth orbit]]
| orbit_periapsis       = {{convert|184|km|nmi|sp=us}}  
| orbit_apoapsis        = {{convert|214|km|nmi|sp=us}}  
| orbit_inclination     = 31.94&nbsp;degrees<ref name="Apollo AS-203">{{Cite web |title=Apollo AS-203 |url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1966-059A |url-status=live |archive-url=https://web.archive.org/web/20240530221748/https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1966-059A |archive-date=2024-05-30 |access-date=2024-10-07 |website=NASA Space Science Data Coordinated Archive}}</ref> 
| orbit_period          = 88.47&nbsp;minutes 
| apsis                 = gee

| previous_mission      = [[AS-201]]
| next_mission          = [[AS-202]]
| programme             = [[Apollo program]]
}}

'''AS-203''' (also known as '''SA-203''' or '''Apollo 3''') was an uncrewed flight of the [[Saturn IB]] rocket on July 5, 1966. It carried no [[command and service module]], as its purpose was to verify the design of the [[S-IVB]] rocket stage restart capability<ref name=":0">{{Cite web |date=2021-07-01 |title=55 Years Ago: Apollo AS-203 Mission Tests Liquid Hydrogen Behavior - NASA |url=https://www.nasa.gov/history/55-years-ago-apollo-as-203-mission-tests-liquid-hydrogen-behavior/ |url-status=live |archive-url=https://web.archive.org/web/20241007160747/https://www.nasa.gov/history/55-years-ago-apollo-as-203-mission-tests-liquid-hydrogen-behavior/ |archive-date=2024-10-07 |access-date=2024-10-07 |language=en-US}}</ref> that would later be used in the [[Apollo program]] to boost astronauts from Earth orbit to a trajectory towards the Moon. It achieved its objectives, but the S-IVB was inadvertently destroyed after four orbits during a differential pressure test that exceeded the design limits.<ref name="Apollo AS-203">{{Cite web |title=Apollo AS-203 |url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1966-059A |url-status=live |archive-url=https://web.archive.org/web/20240530221748/https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1966-059A |archive-date=2024-05-30 |access-date=2024-10-07 |website=NASA Space Science Data Coordinated Archive}}</ref>