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{{short description|Unmanned spaceflight mission; first flight of the Boeing X-37B Orbital Test Vehicle 1}}
{{Use dmy dates|date=December 2012}}
{{Use dmy dates|date=February 2022}}
{{Infobox spaceflight
{{Infobox spaceflight
| name = USA-212
| name = USA-212
Line 6: Line 7:


| mission_type = Demonstration
| mission_type = Demonstration
| operator = [[United States Air Force|U.S. Air Force]]/[[DARPA]]
| operator = [[Air Force Space Command]]
| website =
| website =
| COSPAR_ID = 2010-015A<ref name="heavens-info">{{cite web |url=http://www.heavens-above.com/satinfo.aspx?satid=36514 |title=X-37B - Satellite Information |work=Heavens Above |accessdate=10 July 2013}}</ref>
| COSPAR_ID = 2010-015A<ref name="heavens-info">{{cite web |url=http://www.heavens-above.com/satinfo.aspx?satid=36514 |title=X-37B - Satellite Information |work=Heavens Above |access-date=10 July 2013}}</ref>
| SATCAT = 36514
| SATCAT = 36514
| mission_duration = 224&nbsp;days, 9&nbsp;hours, 24&nbsp;minutes
| mission_duration = 224&nbsp;days, 9&nbsp;hours, 24&nbsp;minutes
Line 15: Line 16:
| manufacturer = [[Boeing]]
| manufacturer = [[Boeing]]
| dry_mass =
| dry_mass =
| launch_mass = {{convert|5400|kg|lb|abbr=on}}<ref name="GSP">{{cite web |url=http://space.skyrocket.de/doc_sdat/x-37.htm |title=X-37B OTV 1, 2, 3 |work=Gunter's Space Page |first=Gunter D. |last=Krebs |accessdate=10 July 2013}}</ref>
| launch_mass = {{convert|5400|kg|lb|abbr=on}}<ref name="GSP">{{cite web |url=http://space.skyrocket.de/doc_sdat/x-37.htm |title=X-37B OTV 1, 2, 3 |work=Gunter's Space Page |first=Gunter D. |last=Krebs |access-date=10 July 2013}}</ref>
| power = Deployable solar array, batteries<ref name="GSP" />
| power = Deployable solar array, batteries<ref name="GSP" />


| launch_date = {{Start-date|22 April 2010, 23:52:00|timezone=yes}}&nbsp;UTC<ref name="nssdc-launch">{{cite web |url=http://nssdc.gsfc.nasa.gov/nmc/spacecraftOrbit.do?id=2010-015A |title=OTV 1: Launch information |work=National Space Science Data Center ''via'' NASA.gov |accessdate=10 July 2013}}</ref>
| launch_date = {{Start-date|22 April 2010, 23:52:00|timezone=yes}}&nbsp;UTC<ref name="nssdc-launch">{{cite web |url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=2010-015A |title=OTV 1: Launch information |work=National Space Science Data Center |publisher=NASA |access-date=10 July 2013}}</ref>
| launch_rocket = [[Atlas V]] 501<ref name="GSP" />
| launch_rocket = [[Atlas V]] 501<ref name="GSP" />
| launch_site = [[Cape Canaveral Air Force Station Space Launch Complex 41|SLC-41]], [[Cape Canaveral Air Force Station|Cape Canaveral]]
| launch_site = [[Cape Canaveral Air Force Station Space Launch Complex 41|SLC-41]], [[Cape Canaveral Air Force Station|Cape Canaveral]]
Line 25: Line 26:
| landing_site = [[Vandenberg Air Force Base|Vandenberg]], Runway&nbsp;12
| landing_site = [[Vandenberg Air Force Base|Vandenberg]], Runway&nbsp;12


| orbit_epoch = 29 November 2010, 04:26:19&nbsp;UTC<ref name="heavens-orbit">{{cite web |url=http://www.heavens-above.com/orbit.aspx?satid=36514 |title=X-37B - Orbit |work=Heavens Above |date=29 November 2010 |accessdate=10 July 2013}}</ref>
| orbit_epoch = 29 November 2010, 04:26:19&nbsp;UTC<ref name="heavens-orbit">{{cite web |url=http://www.heavens-above.com/orbit.aspx?satid=36514 |title=X-37B - Orbit |work=Heavens Above |date=29 November 2010 |access-date=10 July 2013}}</ref>
| orbit_reference = [[geocentric orbit|Geocentric]]
| orbit_reference = [[geocentric orbit|Geocentric]]
| orbit_regime = [[Low Earth orbit|Low Earth]]
| orbit_regime = [[Low Earth orbit|Low Earth]]
Line 36: Line 37:
| orbit_mean_motion = 15.97<ref name="heavens-orbit" />
| orbit_mean_motion = 15.97<ref name="heavens-orbit" />
| apsis = gee
| apsis = gee
| instruments =
| insignia =
| insignia_caption =
| insignia_size =
| programme = '''OTV program'''
| previous_mission =
| next_mission = [[USA-226|OTV-2]]
}}
}}
'''USA-212'''<ref name="heavens-info" /> was the first flight of the [[Boeing]] [[Boeing X-37|X-37B]] '''Orbital Test Vehicle 1''' ('''X-37B OTV-1'''), an American unmanned robotic [[VTHL|vertical-takeoff, horizontal-landing]] (VTHL) [[spaceplane]].
'''USA-212'''<ref name="heavens-info" /> was the first flight of the [[Boeing]] [[Boeing X-37|X-37B]] '''Orbital Test Vehicle 1''' ('''X-37B OTV-1'''), an American robotic [[VTHL|vertical-takeoff, horizontal-landing]] (VTHL) [[spaceplane]].
It was launched aboard an [[Atlas V]] rocket from [[Cape Canaveral Air Force Station|Cape Canaveral]] on 22 April 2010, and operated in [[low Earth orbit]]. Its designation is part of the [[List of USA satellites|USA series]].
It was launched aboard an [[Atlas V]] rocket from [[Cape Canaveral Air Force Station|Cape Canaveral]] on 22 April 2010, and operated in [[low Earth orbit]]. Its designation is part of the [[List of USA satellites|USA series]].


The spaceplane is operated by the [[United States Air Force]], which has not revealed the specific identity of the spaceship's [[Payload (air and space craft)|payload]] for the mission. The Air Force has stated only that the spacecraft would "demonstrate various experiments and allow satellite sensors, subsystems, components, and associated technology to be transported into space and back."<ref>{{cite news |url=http://www.csmonitor.com/USA/Military/2010/0420/Air-Force-to-launch-X-37-space-plane-Precursor-to-war-in-orbit |title=Air Force To Launch X-37 Space Plane: Precursor To War In Orbit? |work=[[The Christian Science Monitor]] |last=Lubold |first=Gordon |date=20 April 2010 |accessdate=23 April 2010}}</ref>
The spaceplane was operated by [[Air Force Space Command]], which has not revealed the specific identity of the spaceship's [[Payload (air and space craft)|payload]] for the mission. The Air Force has stated only that the spacecraft would "demonstrate various experiments and allow satellite sensors, subsystems, components, and associated technology to be transported into space and back."<ref>{{cite news |url=http://www.csmonitor.com/USA/Military/2010/0420/Air-Force-to-launch-X-37-space-plane-Precursor-to-war-in-orbit |title=Air Force To Launch X-37 Space Plane: Precursor To War in Orbit? |work=[[The Christian Science Monitor]] |last=Lubold |first=Gordon |date=20 April 2010 |access-date=23 April 2010}}</ref>


==Launch==
==Launch==
USA-212 was launched on an Atlas&nbsp;V 501 rocket, tail number AV-012, from [[Cape Canaveral Air Force Station Space Launch Complex 41|Space Launch Complex 41]] at the [[Cape Canaveral Air Force Station]] in Florida.<ref>{{cite news |url=http://www.space.com/businesstechnology/091022-x37b-testlaunch.html |title=Air Force's Secretive Space Plane Nears Maiden Voyage |work=Space.com |last=Leonard |first=David |date=22 October 2009}}</ref><ref name="sfnfeb">{{cite news |url=http://spaceflightnow.com/atlas/av012/100225x37arrival/ |title=Air Force X-37B spaceplane arrives in Florida for launch |work=Spaceflight Now |last=Clark |first=Stephen |date=25 February 2010 |accessdate=3 March 2010}}</ref> The launch, which was conducted by [[United Launch Alliance]], occurred at 23:52 [[UTC]] on 22 April 2010, placing the spacecraft into [[low Earth orbit]] for testing.<ref name="SFN-launch">{{cite news |url=http://www.spaceflightnow.com/atlas/av012/100422launch/ |title=Atlas rocket delivers Air Force spaceplane to orbit |work=Spaceflight Now |last=Clark |first=Stephen |date=22 April 2010 |accessdate=23 April 2010}}</ref>
USA-212 was launched on an Atlas&nbsp;V 501 rocket, tail number AV-012, from [[Cape Canaveral Air Force Station Space Launch Complex 41|Space Launch Complex 41]] at the [[Cape Canaveral Air Force Station]] in Florida.<ref>{{cite news |url=http://www.space.com/businesstechnology/091022-x37b-testlaunch.html |title=Air Force's Secretive Space Plane Nears Maiden Voyage |work=Space.com |last=Leonard |first=David |date=22 October 2009}}</ref><ref name="sfnfeb">{{cite news |url=http://spaceflightnow.com/atlas/av012/100225x37arrival/ |title=Air Force X-37B spaceplane arrives in Florida for launch |work=Spaceflight Now |last=Clark |first=Stephen |date=25 February 2010 |access-date=3 March 2010}}</ref> The launch, which was conducted by [[United Launch Alliance]], occurred at 23:52 [[UTC]] on 22 April 2010, placing the spacecraft into [[low Earth orbit]] for testing.<ref name="SFN-launch">{{cite news |url=http://www.spaceflightnow.com/atlas/av012/100422launch/ |title=Atlas rocket delivers Air Force spaceplane to orbit |work=Spaceflight Now |last=Clark |first=Stephen |date=22 April 2010 |access-date=23 April 2010}}</ref>


The X-37B spacecraft was originally intended to be deployed from the payload bay of a NASA [[Space Shuttle]], but following the [[Space Shuttle Columbia disaster|''Columbia'' accident]], it was transferred to a [[Delta II|Delta&nbsp;II 7920]]. It was subsequently transferred to the Atlas&nbsp;V following concerns over the X-37B's aerodynamic properties during launch.<ref name="GSP" />
The X-37B spacecraft was originally intended to be deployed from the payload bay of a NASA [[Space Shuttle]], but following the [[Space Shuttle Columbia disaster|''Columbia'' accident]], it was transferred to a [[Delta II|Delta&nbsp;II 7920]]. It was subsequently transferred to the Atlas&nbsp;V following concerns over the X-37B's aerodynamic properties during launch.<ref name="GSP" />


The launch was the first flight of the Atlas&nbsp;V 501 configuration,<ref name="USAF">{{cite news |url=http://www.af.mil/news/story.asp?id=123201234 |title=Air Force officials launch Atlas&nbsp;V carrying X-37B Orbital Test Vehicle |work=AF.mil |publisher=U.S. Air Force |accessdate=23 April 2010 |date=23 April 2010|archiveurl=http://archive.is/yiF9|archivedate=27 May 2012}}</ref> and the first in four years to use a {{convert|5.4|m|ft|adj=on|sp=us}} [[payload fairing]].<ref name="USAF"/><ref name="JSR-LL">{{cite web |url=http://planet4589.org/space/log/launchlog.txt |title=Launch Log |work=Jonathan's Space Page |last=McDowell |first=Jonathan |accessdate=23 April 2010}}</ref> Prior to the installation of the spacecraft, the Atlas rocket was moved to the launch pad and performed a [[wet dress rehearsal]] on 2 April 2010.<ref name="OddBird">{{cite news |url=http://spaceflightnow.com/atlas/av012/100402x37update/ |title=Air Force spaceplane is an odd bird with a twisted past |work=Spaceflight Now |last=Clark |first=Stephen |date=2 April 2010 |accessdate=23 April 2010}}</ref> It was returned to the [[Vertical Integration Facility]] the next day for final assembly.<ref name="MSC"/> The X-37 arrived at the VIF on 8 April. On 9 April, a 24-hour delay was announced. It subsequently slipped a further 24 hours after the landing of {{OV|103}} on Mission [[STS-131]] was delayed, as the [[Eastern Range]] could not have been reconfigured quickly enough to accommodate both events on the same day.<ref name="MSC">{{cite news |url=http://www.spaceflightnow.com/atlas/av012/status.html |title=Mission Status Center (OTV-1) |work=Spaceflight Now |last=Ray |first=Justin |date=23 April 2010 |accessdate=23 April 2010}}</ref> After a series of delays, it was set for 19 April 2010. On 21 April, the Atlas was rolled back out to the launch pad for launch.<ref name="MSC"/> The launch window on 22 April opened at 23:52 UTC, and closed at 00:01 on 23 April.
The launch was the first flight of the Atlas&nbsp;V 501 configuration,<ref name="USAF">{{cite news |url=http://www.af.mil/news/story.asp?id=123201234 |title=Air Force officials launch Atlas&nbsp;V carrying X-37B Orbital Test Vehicle |work=AF.mil |publisher=U.S. Air Force |access-date=23 April 2010 |date=23 April 2010 |archive-url=https://archive.today/20120527033023/http://www.af.mil/news/story.asp?id=123201234 |archive-date=27 May 2012 |url-status=dead }}</ref> and the first in four years to use a {{convert|5.4|m|ft|adj=on|sp=us}} [[payload fairing]].<ref name="USAF"/><ref name="JSR-LL">{{cite web |url=http://planet4589.org/space/log/launchlog.txt |title=Launch Log |work=Jonathan's Space Page |last=McDowell |first=Jonathan |access-date=23 April 2010}}</ref> Prior to the installation of the spacecraft, the Atlas rocket was moved to the launch pad and performed a [[wet dress rehearsal]] on 2 April 2010.<ref name="OddBird">{{cite news |url=http://spaceflightnow.com/atlas/av012/100402x37update/ |title=Air Force spaceplane is an odd bird with a twisted past |work=Spaceflight Now |last=Clark |first=Stephen |date=2 April 2010 |access-date=23 April 2010}}</ref> It was returned to the [[Vertical Integration Facility]] the next day for final assembly.<ref name="MSC"/> The X-37 arrived at the VIF on 8 April. On 9 April, a 24-hour delay was announced. It subsequently slipped a further 24 hours after the landing of {{OV|103}} on Mission [[STS-131]] was delayed, as the [[Eastern Range]] could not have been reconfigured quickly enough to accommodate both events on the same day.<ref name="MSC">{{cite news |url=http://www.spaceflightnow.com/atlas/av012/status.html |title=Mission Status Center (OTV-1) |work=Spaceflight Now |last=Ray |first=Justin |date=23 April 2010 |access-date=23 April 2010}}</ref> After a series of delays, it was set for 19 April 2010. On 21 April, the Atlas was rolled back out to the launch pad for launch.<ref name="MSC"/> The launch window on 22 April opened at 23:52 UTC, and closed at 00:01 on 23 April.


==Mission==
==Mission==
Most of the mission parameters for the USA-212 flight have not been disclosed.<ref name="sfnfeb"/> The vehicle is capable of being on-orbit for up to 270 days. The Air Force stated the mission time would depend on progress of the craft's experiments during orbit.<ref>{{cite news |url=http://www.aviationweek.com/Article.aspx?id=/article-xml/awx_04_22_2010_p0-222025.xml |title=U.S. Air Force X-37B Launched |work=[[Aviation Week]] |first=Irene |last=Klotz |date=24 April 2010 |access-date=11 July 2013 |archive-date=25 September 2012 |archive-url=https://web.archive.org/web/20120925043241/http://www.aviationweek.com/Article.aspx?id=/article-xml/awx_04_22_2010_p0-222025.xml |url-status=dead }}</ref> Mission control was handled by the [[3d Space Experimentation Squadron|3rd Space Experimentation Squadron]], [[21st Space Wing]], of the [[Air Force Space Command]] in Colorado Springs.<ref name="AFRoundtable20100423">{{cite web |url=http://www.dodlive.mil/index.php/2010/04/air-force-bloggers-roundtable-air-force-set-to-launch-first-x-37b-orbital-test-vehicle/ |title=Air Force Bloggers Roundtable: Air Force set to launch first X-37B Orbital Test Vehicle |work=DODlive.mil |publisher=U.S. Department of Defense |date=20 April 2010 |access-date=23 April 2010 |archive-date=24 April 2010 |archive-url=https://web.archive.org/web/20100424060839/http://www.dodlive.mil/index.php/2010/04/air-force-bloggers-roundtable-air-force-set-to-launch-first-x-37b-orbital-test-vehicle/ |url-status=dead }}</ref>

Most of the mission parameters for the USA-212 flight have not been disclosed.<ref name="sfnfeb"/> The vehicle is capable of being on-orbit for up to 270 days. The Air Force stated the mission time would depend on progress of the craft's experiments during orbit.<ref>{{cite news |url=http://www.aviationweek.com/Article.aspx?id=/article-xml/awx_04_22_2010_p0-222025.xml |title=U.S. Air Force X-37B Launched |work=[[Aviation Week]] |first=Irene |last=Klotz |date=24 April 2010}}</ref> Mission control was handled by the [[3d Space Experimentation Squadron]], [[21st Space Wing]], of the [[Air Force Space Command]] in Colorado Springs.<ref name="AFRoundtable20100423">{{cite web |url=http://www.dodlive.mil/index.php/2010/04/air-force-bloggers-roundtable-air-force-set-to-launch-first-x-37b-orbital-test-vehicle/ |title=Air Force Bloggers Roundtable: Air Force set to launch first X-37B Orbital Test Vehicle |work=DODlive.mil |publisher=U.S. Department of Defense |date=20 April 2010 |accessdate=23 April 2010}}</ref>


===Observations by amateur skywatchers===
===Observations by amateur skywatchers===
In May 2010, an amateur astronomer claimed to spot the spacecraft from his home in [[Toronto]], Ontario, Canada.<ref name=AU-May24>{{cite news |url=http://www.news.com.au/technology/amateur-astronomers-unravel-x37-b-orbit-say-likely-use-for-deploying-spy-satellites/story-e6frfro0-1225870574214 |title=Amateur astronomers unravel X37-B orbit, say likely use for deploying spy satellites |work=News.com.au |date=24 May 2010}}</ref> Shortly after the initial observation, several more detailed observations were made by amateur skywatchers from around the world, who reported the spacecraft to have an almost circular {{convert|401|to|422|km|mi|abbr=on}} low Earth orbit with an inclination of 40°.<ref name=Space-May22>{{cite news |url=http://www.space.com/news/secret-x-37-b-space-plane-spotted-by-amateur-astronomers-100522.html |title=Secret X-37B spaceplane spotted by amateur skywatchers |work=Space.com |first=Leonard |last=David |date=22 May 2010}}</ref> The group believed in their calculations and observations with a high degree of confidence.<ref name=Space-May22/> The spacecraft's [[ground track]] was observed to repeat every four days, which was considered indicative for a possible imaging reconnaissance mission profile.<ref name=Space-May22/><ref name="NYT20100522">{{cite news |url=https://www.nytimes.com/2010/05/23/science/space/23secret.html?pagewanted=all |title=Surveillance Is Suspected as Spacecraft's Main Role |work=[[The New York Times]] |first=William J. |last=Broad |authorlink=William Broad |date=21 May 2010 |accessdate=23 May 2010}}</ref>
In May 2010, an amateur astronomer claimed to spot the spacecraft from his home in [[Toronto]], Ontario, Canada.<ref name=AU-May24>{{cite news |url=http://www.news.com.au/technology/amateur-astronomers-unravel-x37-b-orbit-say-likely-use-for-deploying-spy-satellites/story-e6frfro0-1225870574214 |title=Amateur astronomers unravel X37-B orbit, say likely use for deploying spy satellites |work=News.com.au |date=24 May 2010 |access-date=5 December 2010 |archive-date=27 May 2010 |archive-url=https://web.archive.org/web/20100527025526/http://www.news.com.au/technology/amateur-astronomers-unravel-x37-b-orbit-say-likely-use-for-deploying-spy-satellites/story-e6frfro0-1225870574214 |url-status=dead }}</ref> Shortly after the initial observation, several more detailed observations were made by amateur skywatchers from around the world, who reported the spacecraft to have an almost circular {{convert|401|to|422|km|mi|abbr=on}} low Earth orbit with an inclination of 40°.<ref name=Space-May22>{{cite news |url=http://www.space.com/news/secret-x-37-b-space-plane-spotted-by-amateur-astronomers-100522.html |title=Secret X-37B spaceplane spotted by amateur skywatchers |work=Space.com |first=Leonard |last=David |date=22 May 2010}}</ref> The group believed in their calculations and observations with a high degree of confidence.<ref name=Space-May22/> The spacecraft's [[ground track]] was observed to repeat every four days, which was considered indicative for a possible imaging reconnaissance mission profile.<ref name=Space-May22/><ref name="NYT20100522">{{cite news |url=https://www.nytimes.com/2010/05/23/science/space/23secret.html?pagewanted=all |title=Surveillance Is Suspected as Spacecraft's Main Role |work=[[The New York Times]] |first=William J. |last=Broad |author-link=William Broad |date=21 May 2010 |access-date=23 May 2010}}</ref>


For two weeks, starting on 29 July, the amateur skywatchers were unable to find the spacecraft in the locations they had predicted, leading them to believe it had suddenly changed its course.<ref name=AU-Aug24>{{cite news |url=http://www.news.com.au/technology/us-militarys-top-secret-x-37b-shuttle-disappears-for-two-weeks-changes-orbit/story-e6frfro0-1225909738276 |title=US military's top secret X-37B shuttle 'disappears' for two weeks, changes orbit |work=News.com.au |first=Peter |last=Farquhar |date=25 August 2010}}</ref> During the mission, the vehicle was observed to change its orbit multiple times, with a total [[delta-v]] of the first four orbit changes amounting to {{convert|102| m/s|abbr=on}}. A common characteristic of all the orbits was that the [[ground track]] nearly repeated every few days.<ref name="AU-Aug24"/><ref name="seesat_Nov-2010_0287.html"/> By 12 November 2010, the orbit had been lowered to {{convert|281|by|292|km|mi|abbr=on}} with the ground track now repeating every three days (47 orbits).<ref name="seesat_Nov-2010_0287.html">{{cite web |url=http://www.satobs.org/seesat/Nov-2010/0287.html|title=Updated X-37B OTV 1-1 elements|work=SatObs.org |first=Ted|last=Molczan|accessdate=25 November 2010|date=25 November 2010}}</ref>
For two weeks, starting on 29 July, the amateur skywatchers were unable to find the spacecraft in the locations they had predicted, leading them to believe it had suddenly changed its course.<ref name=AU-Aug24>{{cite news |url=http://www.news.com.au/technology/us-militarys-top-secret-x-37b-shuttle-disappears-for-two-weeks-changes-orbit/story-e6frfro0-1225909738276 |title=US military's top secret X-37B shuttle 'disappears' for two weeks, changes orbit |work=News.com.au |first=Peter |last=Farquhar |date=25 August 2010 |access-date=27 August 2010 |archive-date=28 August 2010 |archive-url=https://web.archive.org/web/20100828022453/http://www.news.com.au/technology/us-militarys-top-secret-x-37b-shuttle-disappears-for-two-weeks-changes-orbit/story-e6frfro0-1225909738276 |url-status=dead }}</ref> During the mission, the vehicle was observed to change its orbit multiple times, with a total [[delta-v]] of the first four orbit changes amounting to {{convert|102| m/s|abbr=on}}. A common characteristic of all the orbits was that the [[ground track]] nearly repeated every few days.<ref name="AU-Aug24"/><ref name="seesat_Nov-2010_0287.html"/> By 12 November 2010, the orbit had been lowered to {{convert|281|by|292|km|mi|abbr=on}} with the ground track now repeating every three days (47 orbits).<ref name="seesat_Nov-2010_0287.html">{{cite web |url=http://www.satobs.org/seesat/Nov-2010/0287.html|title=Updated X-37B OTV 1-1 elements|work=SatObs.org |first=Ted|last=Molczan|access-date=25 November 2010|date=25 November 2010}}</ref>


===Altitude and ground track resonance history===
===Altitude and ground track resonance history===
Line 68: Line 75:
! Resonance<br>(orbits:days)
! Resonance<br>(orbits:days)
|-
|-
| 2010 Apr 22 Aug 9<ref name="MSNBC201008">{{cite news |url=http://www.msnbc.msn.com/id/38831416/ns/technology_and_science-space/ |title=Secret X-37B space plane has changed orbit |work=MSNBC |first=Leonard |last=David |date=24 August 2010 |accessdate=5 December 2010}}</ref>
| 22 April 2010 – 9 August 2010<ref name="MSNBC201008">{{cite news |url=http://www.nbcnews.com/id/38831416 |archive-url=https://web.archive.org/web/20131011160606/http://www.nbcnews.com/id/38831416/ |url-status=dead |archive-date=11 October 2013 |title=Secret X-37B space plane has changed orbit |publisher=NBC News |first=Leonard |last=David |date=24 August 2010 |access-date=5 December 2010}}</ref>
| {{convert|403|km|abbr=on}}<ref name="MSNBC201008"/>
| {{convert|403|km|abbr=on}}<ref name="MSNBC201008"/>
| {{convert|420|km|abbr=on}}<ref name="MSNBC201008"/>
| {{convert|420|km|abbr=on}}<ref name="MSNBC201008"/>
| 61:4<ref name="NYT20100522"/>
| 61:4<ref name="NYT20100522"/>
|-
|-
| 2010 Aug 9 Oct 6<ref name="UniverseToday2010">{{cite news |url=http://www.universetoday.com/75537/secret-x-37b-space-plane-disappears-again/ |title='Secret' X-37B Space Plane Disappears Again |work=Universe Today |first=Nicholos |last=Wethington |date=11 October 2010 |accessdate=5 December 2010}}</ref>
| 9 August 2010 – 6 October 2010<ref name="UniverseToday2010">{{cite news |url=http://www.universetoday.com/75537/secret-x-37b-space-plane-disappears-again/ |title='Secret' X-37B Space Plane Disappears Again |work=Universe Today |first=Nicholos |last=Wethington |date=11 October 2010 |access-date=5 December 2010}}</ref>
| {{convert|433|km|abbr=on}}<ref name="MSNBC201008"/>
| {{convert|433|km|abbr=on}}<ref name="MSNBC201008"/>
| {{convert|444|km|abbr=on}}<ref name="MSNBC201008"/>
| {{convert|444|km|abbr=on}}<ref name="MSNBC201008"/>
| 91:6
| 91:6
|-
|-
| 2010 Oct 6 Nov 1<ref name="SpaceFlightNow201011">{{cite news |url=http://www.spaceflightnow.com/news/n1011/30x37landing/ |title=Secret mini-shuttle due for landing as soon as Friday |work=Spaceflight Now |first=Stephen |last=Clark |date=30 November 2010 |accessdate=5 December 2010}}</ref>
| 6 October 2010 – 1 November 2010<ref name="SpaceFlightNow201011">{{cite news |url=http://www.spaceflightnow.com/news/n1011/30x37landing/ |title=Secret mini-shuttle due for landing as soon as Friday |work=Spaceflight Now |first=Stephen |last=Clark |date=30 November 2010 |access-date=5 December 2010}}</ref>
| {{convert|390|km|abbr=on}}
| {{convert|390|km|abbr=on}}
| {{convert|395|km|abbr=on}}
| {{convert|395|km|abbr=on}}
| 46:3
| 46:3
|-
|-
| 2010 Nov 1 Nov 12<ref name="SpaceFlightNow201011"/>
| 1 November 2010 – 12 November 2010<ref name="SpaceFlightNow201011"/>
| {{convert|315|km|abbr=on}}
| {{convert|315|km|abbr=on}}
| {{convert|328|km|abbr=on}}
| {{convert|328|km|abbr=on}}
| 31:2
| 31:2
|-
|-
| 2010 Nov 12 Dec 3
| 12 November 2010 – 3 December 2010
| {{convert|281|km|abbr=on}}
| {{convert|281|km|abbr=on}}
| {{convert|292|km|abbr=on}}
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After completing its mission, the X-37B was deorbited, [[atmospheric reentry|entered the atmosphere]], and landed at [[Vandenberg Air Force Base]] on 3 December 2010.<ref>{{cite news |url=http://www.spaceflightnow.com/news/n1012/03x37landing/ |title=Home again: U.S. military space plane returns to Earth |work=Spaceflight Now |first=Stephen |last=Clark |date=3 December 2010}}</ref>
After completing its mission, the X-37B was deorbited, [[atmospheric reentry|entered the atmosphere]], and landed at [[Vandenberg Air Force Base]] on 3 December 2010.<ref>{{cite news |url=http://www.spaceflightnow.com/news/n1012/03x37landing/ |title=Home again: U.S. military space plane returns to Earth |work=Spaceflight Now |first=Stephen |last=Clark |date=3 December 2010}}</ref>


The X-37B is the second reusable spacecraft to perform an automated landing after returning from orbit, the first being the Soviet [[Buran (spacecraft)|Buran]] spacecraft in 1988.<ref name="rockets_and_people">{{cite book |url=http://ntrs.nasa.gov/search.jsp?R=20050010181 |title=Rockets and People |volume=1 |publisher=National Aeronautics and Space Administration |series=NASA History Series |first=Boris E. |last=Chertok |editor-first=Asif A. |editor-last=Siddiqi |format=PDF |year=2005 |page=179 |id=SP-2005-4110}}</ref>
The X-37B is the second reusable spacecraft to perform an automated landing after returning from orbit, the first being the Soviet [[Buran (spacecraft)|Buran]] spacecraft in 1988.<ref name="rockets_and_people">{{cite book |url=https://ntrs.nasa.gov/search.jsp?R=20050010181 |title=Rockets and People |volume=1 |publisher=National Aeronautics and Space Administration |series=NASA History Series |first=Boris E. |last=Chertok |editor-first=Asif A. |editor-last=Siddiqi |year=2005 |page=179 |id=SP-2005-4110}}</ref>


==Hypothetical mission components==
==Hypothetical mission components==
As the mission of USA-212 and the X-37B program are classified, public commentary on the program is speculation. [[James Oberg]] speculated that the concurrent launch of Air Force's Hypersonic Technology Vehicle [[DARPA Falcon Project|HTV-2]] was related to the mission. Part of an X-37B's mission profile might involve a simulated enemy attack, which the X-37B should be able to detect and autonomously counteract.<ref>{{cite news |url=http://spectrum.ieee.org/aerospace/space-flight/us-air-force-launches-secret-flying-twinkie |title=U.S. Air Force Launches Secret Flying Twinkie: Military's new space plane tests unnamed powers |work=IEEE Spectrum |first=James |last=Oberg |authorlink=James Oberg |date=31 March 2010 |accessdate=25 April 2010}}</ref> HTV-2 was launched at 23:00 [[UTC]] on 22 April 2010, i.e., 52 minutes ahead of X-37B, from [[Vandenberg Air Force Base]] in California,<ref>{{cite news |url=http://www.spaceflightnow.com/news/n1004/23minotaur/index.html |title=New Minotaur rocket launches on suborbital flight |work=Spaceflight Now |first=Stephen |last=Clark |date=23 April 2010 |accessdate=25 April 2010}}</ref> on a suborbital trajectory supposed to last less than 25 min.<ref name="Mach 20">{{cite journal |url=http://www.airspacemag.com/flight-today/hypersonics.html?story=fullstory |title=Mach 20 or Bust |journal=[[Air & Space]] |first=Geoffrey |last=Little |date=1 September 2007}}</ref> The mission failed and was aborted nine minutes after launch.<ref>{{cite press release |url=http://www.darpa.mil/WorkArea/DownloadAsset.aspx?id=2147484133 |title=Falcon HTV-2 Launch Tests Hypersonic Vehicle Flight Capabilities |publisher=[[DARPA]] |format=PDF |first=Johanna |last=Jones |date=23 April 2010 |accessdate=5 December 2010}}</ref><ref>{{cite press release |url=http://www.darpa.mil/WorkArea/DownloadAsset.aspx?id=2147484134 |title=DARPA Concludes Review of Falcon HTV-2 Flight Anomaly |work=[[DARPA]] |format=PDF |date=16 November 2010 |accessdate=5 December 2010}}</ref>
As the mission of USA-212 and the X-37B program are classified, public commentary on the program is speculation. [[James Oberg]] speculated that the concurrent launch of Air Force's Hypersonic Technology Vehicle [[DARPA Falcon Project|HTV-2]] was related to the mission. Part of an X-37B's mission profile might involve a simulated enemy attack, which the X-37B should be able to detect and autonomously counteract.<ref>{{cite news |url=https://spectrum.ieee.org/us-air-force-launches-secret-flying-twinkie |title=U.S. Air Force Launches Secret Flying Twinkie: Military's new space plane tests unnamed powers |work=IEEE Spectrum |first=James |last=Oberg |author-link=James Oberg |date=31 March 2010 |access-date=25 April 2010}}</ref> HTV-2 was launched at 23:00 [[UTC]] on 22 April 2010, i.e., 52 minutes ahead of X-37B, from [[Vandenberg Air Force Base]] in California,<ref>{{cite news |url=http://www.spaceflightnow.com/news/n1004/23minotaur/index.html |title=New Minotaur rocket launches on suborbital flight |work=Spaceflight Now |first=Stephen |last=Clark |date=23 April 2010 |access-date=25 April 2010}}</ref> on a suborbital trajectory supposed to last less than 25 min.<ref name="Mach 20">{{cite journal |url=http://www.airspacemag.com/flight-today/hypersonics.html?story=fullstory |title=Mach 20 or Bust |journal=[[Air & Space]] |first=Geoffrey |last=Little |date=1 September 2007}}</ref> The mission failed and was aborted nine minutes after launch.<ref>{{cite press release |url=http://www.darpa.mil/WorkArea/DownloadAsset.aspx?id=2147484133 |title=Falcon HTV-2 Launch Tests Hypersonic Vehicle Flight Capabilities |publisher=[[DARPA]] |first=Johanna |last=Jones |date=23 April 2010 |access-date=5 December 2010 |url-status=dead |archive-url=https://web.archive.org/web/20120804194505/http://www.darpa.mil/WorkArea/DownloadAsset.aspx?id=2147484133 |archive-date=4 August 2012 }}</ref><ref>{{cite press release |url=http://www.darpa.mil/WorkArea/DownloadAsset.aspx?id=2147484134 |title=DARPA Concludes Review of Falcon HTV-2 Flight Anomaly |work=[[DARPA]] |date=16 November 2010 |access-date=5 December 2010 |url-status=dead |archive-url=https://web.archive.org/web/20120804193948/http://www.darpa.mil/WorkArea/DownloadAsset.aspx?id=2147484134 |archive-date=4 August 2012 }}</ref>


William Scott, coauthor of the techno-novel ''Counterspace: The Next Hours of World War&nbsp;III'' and former Rocky Mountain Bureau Chief for ''Aviation Week & Space Technology'' magazine believes that with X-37B, the Air Force might test weapon delivery from a space plane in low Earth orbit. He mentions [[Kinetic bombardment|Rods from God]] as a possible scenario.<ref>{{cite news |url=http://www.space.com/8195-air-force-mystery-37b-space-plane-fuels-speculation.html |title=Air Force's Mystery X-37B Space Plane Fuels Speculation |work=Space.com |first=Leonard |last=David |date=12 April 2010}}</ref> This hypothesis aligns with speculation that the launch of USA-212 marks the beginning of [[Militarisation of space|military operations in space]].<ref>{{cite AV media |url=http://www.cnn.com/video/?/video/tech/2010/04/23/starr.mystery.plane.cnn |title=Mystery military space plane |work=CNN.com |first=Barbara |last=Starr |type=Video |date=23 April 2010}}</ref>
William Scott, coauthor of the techno-novel ''Counterspace: The Next Hours of World War&nbsp;III'' and former Rocky Mountain Bureau Chief for ''Aviation Week & Space Technology'' magazine believes that with X-37B, the Air Force might test weapon delivery from a space plane in low Earth orbit. He mentions [[Kinetic bombardment|Rods from God]] as a possible scenario.<ref>{{cite news |url=http://www.space.com/8195-air-force-mystery-37b-space-plane-fuels-speculation.html |title=Air Force's Mystery X-37B Space Plane Fuels Speculation |work=Space.com |first=Leonard |last=David |date=12 April 2010}}</ref> This hypothesis aligns with speculation that the launch of USA-212 marks the beginning of [[Militarisation of space|military operations in space]].<ref>{{cite AV media |url=http://www.cnn.com/video/?/video/tech/2010/04/23/starr.mystery.plane.cnn |title=Mystery military space plane |publisher=CNN|first=Barbara |last=Starr |type=Video |date=23 April 2010}}</ref>


==See also==
==See also==
{{Portal|Spaceflight}}
*[[2010 in spaceflight]]
*[[2010 in spaceflight]]
*[[Lockheed Martin X-33]]
*[[Lockheed Martin X-33]]
*[[USA-226]]
*[[USA-226]]
*[[List of USA satellites]]


==References==
==References==
{{Reflist|2}}
{{Reflist}}


{{X-37B flights}}
{{X-37B flights}}
{{Orbital launches in 2010}}
{{Orbital launches in 2010}}


{{DEFAULTSORT:Usa-212}}
[[Category:Spacecraft launched in 2010]]
[[Category:Spacecraft launched in 2010]]
[[Category:DARPA]]
[[Category:DARPA]]
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[[Category:Spacecraft which reentered in 2010]]
[[Category:Spacecraft which reentered in 2010]]
[[Category:USA satellites]]
[[Category:USA satellites]]
[[Category:Boeing X-37]]

Latest revision as of 19:58, 3 August 2024

USA-212
OTV-1 during encapsulation prior to maiden launch
Mission typeDemonstration
OperatorAir Force Space Command
COSPAR ID2010-015A[1]
SATCAT no.36514
Mission duration224 days, 9 hours, 24 minutes
Spacecraft properties
Spacecraft typeBoeing X-37B
ManufacturerBoeing
Launch mass5,400 kg (11,900 lb)[2]
PowerDeployable solar array, batteries[2]
Start of mission
Launch date22 April 2010, 23:52:00 (2010-04-22UTC23:52Z) UTC[3]
RocketAtlas V 501[2]
Launch siteSLC-41, Cape Canaveral
ContractorUnited Launch Alliance
End of mission
Landing date3 December 2010, 09:16:00 (2010-12-03UTC09:17Z) UTC[4]
Landing siteVandenberg, Runway 12
Orbital parameters
Reference systemGeocentric
RegimeLow Earth
Semi-major axis6,598 km (4,100 mi)[5]
Eccentricity0.0006[5]
Perigee altitude279 km (173 mi)[5]
Apogee altitude287 km (178 mi)[5]
Inclination39.9979°[5]
Period88.9 min[5]
Mean motion15.97[5]
Epoch29 November 2010, 04:26:19 UTC[5]
OTV program
OTV-2 →

USA-212[1] was the first flight of the Boeing X-37B Orbital Test Vehicle 1 (X-37B OTV-1), an American robotic vertical-takeoff, horizontal-landing (VTHL) spaceplane. It was launched aboard an Atlas V rocket from Cape Canaveral on 22 April 2010, and operated in low Earth orbit. Its designation is part of the USA series.

The spaceplane was operated by Air Force Space Command, which has not revealed the specific identity of the spaceship's payload for the mission. The Air Force has stated only that the spacecraft would "demonstrate various experiments and allow satellite sensors, subsystems, components, and associated technology to be transported into space and back."[6]

Launch

[edit]

USA-212 was launched on an Atlas V 501 rocket, tail number AV-012, from Space Launch Complex 41 at the Cape Canaveral Air Force Station in Florida.[7][8] The launch, which was conducted by United Launch Alliance, occurred at 23:52 UTC on 22 April 2010, placing the spacecraft into low Earth orbit for testing.[9]

The X-37B spacecraft was originally intended to be deployed from the payload bay of a NASA Space Shuttle, but following the Columbia accident, it was transferred to a Delta II 7920. It was subsequently transferred to the Atlas V following concerns over the X-37B's aerodynamic properties during launch.[2]

The launch was the first flight of the Atlas V 501 configuration,[10] and the first in four years to use a 5.4-meter (18 ft) payload fairing.[10][11] Prior to the installation of the spacecraft, the Atlas rocket was moved to the launch pad and performed a wet dress rehearsal on 2 April 2010.[12] It was returned to the Vertical Integration Facility the next day for final assembly.[13] The X-37 arrived at the VIF on 8 April. On 9 April, a 24-hour delay was announced. It subsequently slipped a further 24 hours after the landing of Space Shuttle Discovery on Mission STS-131 was delayed, as the Eastern Range could not have been reconfigured quickly enough to accommodate both events on the same day.[13] After a series of delays, it was set for 19 April 2010. On 21 April, the Atlas was rolled back out to the launch pad for launch.[13] The launch window on 22 April opened at 23:52 UTC, and closed at 00:01 on 23 April.

Mission

[edit]

Most of the mission parameters for the USA-212 flight have not been disclosed.[8] The vehicle is capable of being on-orbit for up to 270 days. The Air Force stated the mission time would depend on progress of the craft's experiments during orbit.[14] Mission control was handled by the 3rd Space Experimentation Squadron, 21st Space Wing, of the Air Force Space Command in Colorado Springs.[15]

Observations by amateur skywatchers

[edit]

In May 2010, an amateur astronomer claimed to spot the spacecraft from his home in Toronto, Ontario, Canada.[16] Shortly after the initial observation, several more detailed observations were made by amateur skywatchers from around the world, who reported the spacecraft to have an almost circular 401 to 422 km (249 to 262 mi) low Earth orbit with an inclination of 40°.[17] The group believed in their calculations and observations with a high degree of confidence.[17] The spacecraft's ground track was observed to repeat every four days, which was considered indicative for a possible imaging reconnaissance mission profile.[17][18]

For two weeks, starting on 29 July, the amateur skywatchers were unable to find the spacecraft in the locations they had predicted, leading them to believe it had suddenly changed its course.[19] During the mission, the vehicle was observed to change its orbit multiple times, with a total delta-v of the first four orbit changes amounting to 102 m/s (330 ft/s). A common characteristic of all the orbits was that the ground track nearly repeated every few days.[19][20] By 12 November 2010, the orbit had been lowered to 281 by 292 km (175 by 181 mi) with the ground track now repeating every three days (47 orbits).[20]

Altitude and ground track resonance history

[edit]

Based on data collected by amateur observers, the following orbital characteristics were calculated by amateur skywatcher Ted Molczan.

Time period Periapsis
(AMSL)
Apoapsis
(AMSL)
Resonance
(orbits:days)
22 April 2010 – 9 August 2010[21] 403 km (250 mi)[21] 420 km (260 mi)[21] 61:4[18]
9 August 2010 – 6 October 2010[22] 433 km (269 mi)[21] 444 km (276 mi)[21] 91:6
6 October 2010 – 1 November 2010[4] 390 km (240 mi) 395 km (245 mi) 46:3
1 November 2010 – 12 November 2010[4] 315 km (196 mi) 328 km (204 mi) 31:2
12 November 2010 – 3 December 2010 281 km (175 mi) 292 km (181 mi) 47:3

Landing

[edit]
Infrared view of OTV1 after landing

After completing its mission, the X-37B was deorbited, entered the atmosphere, and landed at Vandenberg Air Force Base on 3 December 2010.[23]

The X-37B is the second reusable spacecraft to perform an automated landing after returning from orbit, the first being the Soviet Buran spacecraft in 1988.[24]

Hypothetical mission components

[edit]

As the mission of USA-212 and the X-37B program are classified, public commentary on the program is speculation. James Oberg speculated that the concurrent launch of Air Force's Hypersonic Technology Vehicle HTV-2 was related to the mission. Part of an X-37B's mission profile might involve a simulated enemy attack, which the X-37B should be able to detect and autonomously counteract.[25] HTV-2 was launched at 23:00 UTC on 22 April 2010, i.e., 52 minutes ahead of X-37B, from Vandenberg Air Force Base in California,[26] on a suborbital trajectory supposed to last less than 25 min.[27] The mission failed and was aborted nine minutes after launch.[28][29]

William Scott, coauthor of the techno-novel Counterspace: The Next Hours of World War III and former Rocky Mountain Bureau Chief for Aviation Week & Space Technology magazine believes that with X-37B, the Air Force might test weapon delivery from a space plane in low Earth orbit. He mentions Rods from God as a possible scenario.[30] This hypothesis aligns with speculation that the launch of USA-212 marks the beginning of military operations in space.[31]

See also

[edit]

References

[edit]
  1. ^ a b "X-37B - Satellite Information". Heavens Above. Retrieved 10 July 2013.
  2. ^ a b c d Krebs, Gunter D. "X-37B OTV 1, 2, 3". Gunter's Space Page. Retrieved 10 July 2013.
  3. ^ "OTV 1: Launch information". National Space Science Data Center. NASA. Retrieved 10 July 2013.
  4. ^ a b c Clark, Stephen (30 November 2010). "Secret mini-shuttle due for landing as soon as Friday". Spaceflight Now. Retrieved 5 December 2010.
  5. ^ a b c d e f g h "X-37B - Orbit". Heavens Above. 29 November 2010. Retrieved 10 July 2013.
  6. ^ Lubold, Gordon (20 April 2010). "Air Force To Launch X-37 Space Plane: Precursor To War in Orbit?". The Christian Science Monitor. Retrieved 23 April 2010.
  7. ^ Leonard, David (22 October 2009). "Air Force's Secretive Space Plane Nears Maiden Voyage". Space.com.
  8. ^ a b Clark, Stephen (25 February 2010). "Air Force X-37B spaceplane arrives in Florida for launch". Spaceflight Now. Retrieved 3 March 2010.
  9. ^ Clark, Stephen (22 April 2010). "Atlas rocket delivers Air Force spaceplane to orbit". Spaceflight Now. Retrieved 23 April 2010.
  10. ^ a b "Air Force officials launch Atlas V carrying X-37B Orbital Test Vehicle". AF.mil. U.S. Air Force. 23 April 2010. Archived from the original on 27 May 2012. Retrieved 23 April 2010.
  11. ^ McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved 23 April 2010.
  12. ^ Clark, Stephen (2 April 2010). "Air Force spaceplane is an odd bird with a twisted past". Spaceflight Now. Retrieved 23 April 2010.
  13. ^ a b c Ray, Justin (23 April 2010). "Mission Status Center (OTV-1)". Spaceflight Now. Retrieved 23 April 2010.
  14. ^ Klotz, Irene (24 April 2010). "U.S. Air Force X-37B Launched". Aviation Week. Archived from the original on 25 September 2012. Retrieved 11 July 2013.
  15. ^ "Air Force Bloggers Roundtable: Air Force set to launch first X-37B Orbital Test Vehicle". DODlive.mil. U.S. Department of Defense. 20 April 2010. Archived from the original on 24 April 2010. Retrieved 23 April 2010.
  16. ^ "Amateur astronomers unravel X37-B orbit, say likely use for deploying spy satellites". News.com.au. 24 May 2010. Archived from the original on 27 May 2010. Retrieved 5 December 2010.
  17. ^ a b c David, Leonard (22 May 2010). "Secret X-37B spaceplane spotted by amateur skywatchers". Space.com.
  18. ^ a b Broad, William J. (21 May 2010). "Surveillance Is Suspected as Spacecraft's Main Role". The New York Times. Retrieved 23 May 2010.
  19. ^ a b Farquhar, Peter (25 August 2010). "US military's top secret X-37B shuttle 'disappears' for two weeks, changes orbit". News.com.au. Archived from the original on 28 August 2010. Retrieved 27 August 2010.
  20. ^ a b Molczan, Ted (25 November 2010). "Updated X-37B OTV 1-1 elements". SatObs.org. Retrieved 25 November 2010.
  21. ^ a b c d e David, Leonard (24 August 2010). "Secret X-37B space plane has changed orbit". NBC News. Archived from the original on 11 October 2013. Retrieved 5 December 2010.
  22. ^ Wethington, Nicholos (11 October 2010). "'Secret' X-37B Space Plane Disappears Again". Universe Today. Retrieved 5 December 2010.
  23. ^ Clark, Stephen (3 December 2010). "Home again: U.S. military space plane returns to Earth". Spaceflight Now.
  24. ^ Chertok, Boris E. (2005). Siddiqi, Asif A. (ed.). Rockets and People. NASA History Series. Vol. 1. National Aeronautics and Space Administration. p. 179. SP-2005-4110.
  25. ^ Oberg, James (31 March 2010). "U.S. Air Force Launches Secret Flying Twinkie: Military's new space plane tests unnamed powers". IEEE Spectrum. Retrieved 25 April 2010.
  26. ^ Clark, Stephen (23 April 2010). "New Minotaur rocket launches on suborbital flight". Spaceflight Now. Retrieved 25 April 2010.
  27. ^ Little, Geoffrey (1 September 2007). "Mach 20 or Bust". Air & Space.
  28. ^ Jones, Johanna (23 April 2010). "Falcon HTV-2 Launch Tests Hypersonic Vehicle Flight Capabilities" (Press release). DARPA. Archived from the original on 4 August 2012. Retrieved 5 December 2010.
  29. ^ "DARPA Concludes Review of Falcon HTV-2 Flight Anomaly". DARPA (Press release). 16 November 2010. Archived from the original on 4 August 2012. Retrieved 5 December 2010.
  30. ^ David, Leonard (12 April 2010). "Air Force's Mystery X-37B Space Plane Fuels Speculation". Space.com.
  31. ^ Starr, Barbara (23 April 2010). Mystery military space plane (Video). CNN.