The '''Boeing Small Launch Vehicle''', or '''SLV''', is an [[air launch to orbit|air-launched]] three-stage-to-orbit [[launch vehicle]] concept aimed to launch small [[Payload (air and space craft)|payloads]] of {{convert|100|lb|kg}} into [[low Earth orbit]]. The program is proposed to drive down launch costs for [[smallsat|small satellite]]s as low as {{currency|300000|USD}} per launch ($7,000/kg) and could be fielded by 2020.<ref name=aw20120521>{{cite news |last=Norris |first=Guy |title=Boeing Unveils Air-Launched Space-Access Concept |url=http://www.aviationweek.com/Article.aspx?id=/article-xml/AW_05_21_2012_p25-458597.xml&p=1 |accessdate=2012-05-23 |newspaper=Aviation Week |date=2012-05-21 |archive-date=2013-03-26 |archive-url=https://web.archive.org/web/20130326232014/http://www.aviationweek.com/Article.aspx?id=%2Farticle-xml%2FAW_05_21_2012_p25-458597.xml&p=1 |url-status=dead }}</ref> {{Update inline|date=December 2021}}
==History== In July 2012, [[DARPA]] awarded Boeing a US$4.5 million contract to further refine the system concept as a part of the [[DARPA ALASA]] program.<ref name=pa20120702> {{cite news |last=Messier|first=Doug |title=DARPA Awards 6 Small Airborne Launch Vehicle Contracts |url=http://www.parabolicarc.com/2012/07/02/darpa-awards-6-small-airborne-launch-vehicle-contracts/ |accessdate=2012-11-29 |newspaper=Parabolic Arc |date=2012-07-02 }}</ref>
==Description== The first stage of the three-stage launcher would be an air-launched [[supersonic aircraft]] accelerating to a speed of {{convert|4.5|Mach}} at {{convert|61000|ft}}, while the second stage would be a [[Hypersonic flight|hypersonic]] [[waverider]] aircraft which would accelerate the vehicle to {{convert|10|Mach}} at an altitude of {{convert|95000|ft}}. Both of the first two stages would be [[reusable launch vehicle|reusable]] to reduce launch cost, and both stages would carry only fuel, and obtain their oxygen for combustion from the [[Atmosphere of Earth|Earth's atmosphere]].<ref name=aw20120521/> The third stage would be powered by a [[rocket]], roughly {{convert|16|ft}} long, to complete the acceleration of the {{convert|21|x|38|in|cm}} payload to [[Orbital speed|orbital velocity]]. The carrier aircraft is projected to be a [[Scaled Composites White Knight Two]].<ref name=aw20120521/>
===Specifications=== *First-stage: {{convert|38|ft}} length, {{convert|19|ft}} [[wingspan]], [[supersonic aircraft]]<ref name=aw20120512>{{cite news |title=More on Boeing's small launcher concept |url=http://www.aviationweek.com/Blogs.aspx?plckPostId=Blog:a68cb417-3364-4fbf-a9dd-4feda680ec9cPost:f6f267a4-b412-44cc-a2a0-5258308c847e |archive-url=https://archive.today/20130118044523/http://www.aviationweek.com/Blogs.aspx?plckPostId=Blog:a68cb417-3364-4fbf-a9dd-4feda680ec9cPost:f6f267a4-b412-44cc-a2a0-5258308c847e |url-status=dead |archive-date=18 January 2013 |accessdate=4 Aug 2012 |newspaper=Aviation Week |date=22 May 2012 }}</ref> *Second-stage: {{convert|37|ft}} in length, {{convert|15.3|ft}} wingspan, [[Hypersonic flight|hypersonic aircraft]]; "Overall airframe construction would be of [[Carbon-fiber-reinforced polymer|graphite-epoxy]], with an integral conformal [[Methane#Developing technologies|liquid methane]] tank to supply the vehicle’s circular combustion [[scramjet]]. [[Thermal protection system|Thermal protection]] would be a [[Ceramic matrix composite|ceramic matrix]] [[composite material]]."<ref name=aw20120512/> *Third-stage: {{convert|2|ft}} diameter, {{convert|16.4|ft}} long, [[solid propellant]] rocket.<ref name=aw20120512/> *Payload: {{convert|21|in|m}} diameter, {{convert|38|in|m}} long payload bay, carrying up to {{convert|100|lb}} to [[low Earth orbit]].<ref name=aw20120512/>
==See also== * [[Boeing X-51|X-51 WaveRider]] [[hypersonic]] test vehicle flown at {{convert|5.1|Mach|sigfig=2|60,000}} at {{convert|60000|ft}} on a single test mission in May 2013.
==References== {{Reflist}}
[[Category:Proposed space launch vehicles]]