Editing AS-101

{{Short description|1964 Apollo Program test flight}}
{{use mdy dates|date=September 2021}}
{{Infobox spaceflight
| name                  = AS-101 
| image                 = Saturn SA6 on launch pad.jpg
| image_caption         = AS-101 (SA-6)
| insignia              =

| mission_type          = Spacecraft aerodynamics
| operator              = [[NASA]]
| COSPAR_ID             = 1964-025A 
| SATCAT                = 800
| mission_duration      = ~5&nbsp;hours, 53&nbsp;minutes
| orbits_completed      = 54
| distance_travelled    =

| spacecraft            = [[Apollo (spacecraft)|Apollo]] BP-13
| manufacturer          = 
| launch_mass           = {{convert|17000|lb|kg|disp=flip|sp=us}}
| landing_mass          =

| launch_date           = {{start date text|May 28, 1964, 17:07:00|timezone=yes}}&nbsp;UTC 
| launch_rocket         = [[Saturn I]] SA-6
| launch_site           = [[Cape Canaveral Air Force Station|Cape Kennedy]] [[Cape Canaveral Air Force Station Space Launch Complex 37|LC-37B]]

| disposal_type         = Uncontrolled reentry
| last_contact          = {{end date text|May 28, 1964}} after 4 orbits
| decay_date            = June 1, 1964

| orbit_epoch           = 30 May 1964<ref name="satcat">{{cite web|url=http://planet4589.org/space/log/satcat.txt|title=Satellite Catalog|first=Jonathan|last=McDowell|work=Jonathan's Space Page|access-date=31 October 2013}}</ref>
| orbit_reference       = [[geocentric orbit|Geocentric]]
| orbit_regime          = [[Low Earth orbit]]
| orbit_periapsis       = {{convert|178|km|nmi|sp=us}} 
| orbit_apoapsis        = {{convert|199|km|nmi|sp=us}} 
| orbit_inclination     = 31.7&nbsp;degrees
| orbit_period          = 88.26&nbsp;minutes 
| apsis                 = gee
| previous_mission      = [[Saturn I SA-5|SA-5]]
| next_mission          = [[AS-102]]
| programme             = [[Apollo program]]
}}

'''AS-101''' (also designated '''SA-6''') was the sixth flight of the [[Saturn I]] launch vehicle, which carried the first [[Boilerplate (spaceflight)|boilerplate]] [[Apollo spacecraft]] into low Earth orbit.<ref>{{Cite web |url=http://science.ksc.nasa.gov/history/apollo/sa-6/sa-6.html |title=NASA: ''SA-6'' |access-date=December 8, 2003 |archive-date=May 14, 2011 |archive-url=https://web.archive.org/web/20110514001106/http://science.ksc.nasa.gov/history/apollo/sa-6/sa-6.html |url-status=dead }}</ref><ref name="NSSDC">[https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1964-025A NSSDC: ''SA-6'']</ref> The test took place on May 28, 1964, lasting for four orbits (about six hours). The spacecraft and its upper stage completed a total of 54 orbits before reentering the atmosphere and crashing in the Pacific Ocean on June 1, 1964.

The flight experienced a single anomaly: one of the eight first-stage Saturn I engines shut down early, but the guidance system compensated by burning the remaining seven engines longer. AS-101 was followed by four more flights to verify the launch aerodynamics of the [[Apollo command and service module]] (CSM) and its [[launch escape system]] (LES) tower.

==Boilerplate Apollo ==
The first five launches of the Saturn I had carried [[PGM-19 Jupiter|Jupiter]] nosecones, a proven design which allowed engineers to focus on development of the rocket. To verify the  launch aerodynamics of the CSM, AS-101 carried BP-13, a [[boilerplate (spacecraft)|boilerplate spacecraft]] that weighed {{convert|17000|lb|kg}} and duplicated the size and shape of the CSM, and a dummy LES tower. A flight-weight command module (CM) weighed around {{convert|12000|lb|kg}}.<ref name="NSSDC"/> The boilerplate spacecraft was instrumented with 116 sensors reading strain, pressure, temperature, heat flux, and acceleration.

== Flight ==
[[File:VonBraunMuellerReesSA6.jpg|thumb|left|[[George Mueller (NASA)|George Mueller]], [[Wernher von Braun]], and [[Eberhard Rees]] ([[Lyndon B. Johnson Space Center|MSFC]] Director for Research and Development) watch the AS-101 launch from the firing room.]]
It took three attempts to launch the rocket from [[Cape Canaveral Air Force Station Space Launch Complex 37|Cape Kennedy Air Force Station Space Launch Complex 37B]]. The first attempt was scrubbed after the [[liquid oxygen]] damaged a wire mesh screen during a test, causing fuel contamination. The second attempt was scrubbed after the rocket's guidance system overheated due to failure of an air conditioning compressor.

The vehicle finally lifted off on May 28, 1964. There had been several delays during the countdown as liquid oxygen vapors obscured an optical window in the SA-6's instrument unit, so that a ground-based [[theodolite]] could not see it. This theodolite was required by the countdown computer in order for launch to proceed. Engineers deemed it non-critical and reprogrammed the computer, allowing the launch to proceed.

The ascent was normal up to 116.9 seconds after liftoff, at which point engine number eight shut off early. This was not planned, as it had been on [[SA-4 (Apollo)|SA-4]] as a test, but the rocket compensated perfectly by burning the remaining fuel in the other seven engines for 2.7 seconds longer than planned. The first stage separated and the second stage ignited. Ten seconds later, the launch escape system was jettisoned as planned. Also jettisoned from the first stage were eight film cameras that observed separation of the stages.

The second stage cut off at 624.5 seconds after launch (1.26 seconds earlier than predicted), with the stage and boilerplate spacecraft in a {{Convert|182|km|nmi|abbr=off|sp=us}} by {{Convert|227|km|nmi|abbr=off|sp=us}} orbit. It continued to transmit data for four orbits, after which the batteries failed. The vehicle made a total of 54 orbits, re-entering the atmosphere east of [[Kanton Island]] in the [[Pacific Ocean]] on June 1.

== Engine failure cause ==
Engineers were quick to find the cause of the failure of engine number eight. The teeth on one of the gears in the [[turbopump]] were stripped off. This did not cause any delays in the next launches as engineers had already decided that the gear design was inferior and were planning to change it for the next launch. This was the only problem encountered with an [[H-1 (rocket engine)|H-1]] engine during a flight.

{{Clear}}

== References ==
{{Portal|Spaceflight}}
{{Include-NASA}}
{{Reflist}}

== External links ==
{{commons category}}
*[http://www.hq.nasa.gov/office/pao/History/SP-4009/cover.htm The Apollo Spacecraft: A Chronology] {{Webarchive|url=https://web.archive.org/web/20171209084600/http://www.hq.nasa.gov/office/pao/History/SP-4009/cover.htm |date=December 9, 2017 }}
*[https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1964-025A NASA Space Science Data Coordinated Archive]
*[http://www.hq.nasa.gov/office/pao/History/SP-4204/cover.html Moonport: A History of Apollo Launch Facilities and Operations] {{Webarchive|url=https://web.archive.org/web/20110318012712/http://www.hq.nasa.gov/office/pao/History/SP-4204/cover.html |date=March 18, 2011 }}
*http://science.ksc.nasa.gov/history/apollo/sa-6/sa-6.html {{Webarchive|url=https://web.archive.org/web/20110514001106/http://science.ksc.nasa.gov/history/apollo/sa-6/sa-6.html |date=May 14, 2011 }}
*[https://history.nasa.gov/SP-4206/sp4206.htm Stages to Saturn]
*[http://hdl.handle.net/2060/19790077210 Postlaunch Report for Apollo Mission A-101]

{{Apollo program| before=[[SA-5 (Apollo)|SA-5]] <br /> [[A-001]]| after=[[AS-102]]}}
{{Orbital launches in 1964}}

{{Use American English|date=January 2014}}

[[Category:Apollo program]]
[[Category:Spacecraft launched in 1964]]
[[Category:Spacecraft which reentered in 1964]]
[[Category:Test spaceflights]]
[[Category:Spacecraft launched by Saturn rockets]]
[[Category:Saturn I]]