View source for Astronomy:Reusable launch system

{{Short description|Launch system designed for repeated use and reusability}}

[[File:Space Shuttle Columbia launching cropped 2.jpg|thumb|upright|alt=The Space Shuttle Columbia launching on the first Space Shuttle mission|The first (partially) reusable space launch system, the [[Engineering:Space Shuttle Columbia|Space Shuttle ''Columbia'']], at its first launch 1981 (STS-1).]]

A '''reusable launch system''' is a launch system that allows for the reuse of some or all of the component stages. To date, several fully reusable [[Engineering:Suborbital|suborbital]] systems and partially reusable [[Engineering:Orbital spaceflight|orbital]] systems have been flown.

The first reusable spacecraft to reach orbit was the [[Engineering:Space Shuttle|Space Shuttle]] (in 1981), which failed to accomplish the intended goal of reducing launch costs to below those of [[Engineering:Expendable launch system|expendable launch system]]s.

During the 21st century, commercial interest in reusable launch systems has grown considerably, with several active launchers. [[Company:SpaceX|SpaceX]] CEO [[Biography:Elon Musk|Elon Musk]] has said that if one can figure out how to reuse rockets like airplanes then the cost of access to space will be reduced by as much as a factor of a hundred.<ref>{{cite web|title=Reusability|url=https://www.spacex.com/reusability-key-making-human-life-multi-planetary|access-date=November 20, 2019|archive-date=January 15, 2020|archive-url=https://web.archive.org/web/20200115131159/https://www.spacex.com/reusability-key-making-human-life-multi-planetary|url-status=dead}}</ref>  SpaceX's [[Engineering:Falcon 9|Falcon 9]] rocket has a reusable first stage and capsule (for [[Engineering:SpaceX Dragon|Dragon]] flights) with an expendable second stage.  SpaceX has been developing a reusable second stage since the late 2010s which, if successful, could make possible the first fully-reusable [[Engineering:Orbital spaceflight|orbital]] [[Engineering:Launch vehicle|launch vehicle]] during the 2020s. [[Company:Virgin Galactic|Virgin Galactic]] has flown reusable suborbital [[Engineering:SpaceShipTwo|spaceplanes]], and the suborbital [[Company:Blue Origin|Blue Origin]] [[Astronomy:New Shepard|New Shepard]] rocket has a recoverable boost stage and [[Engineering:Space capsule|passenger capsule]].

==Configurations==
Reusable launch systems may be either fully- or partially-reusable.

=== Fully-reusable launch vehicle ===
{{asof|2021|08}}, fully-reusable [[Engineering:Orbital spaceflight|orbital]] systems have yet to be built and made operational. Fully-reusable launch vehicles could theoretically be [[Astronomy:Single-stage-to-orbit|single-stage-to-orbit]] (SSTO) vehicles, as well as [[Astronomy:Multistage rocket|multi-stage-to orbit]] systems. 

Three companies are currently in development to achieve fully-reusable launch vehicles as of July 2021. Each of them is working on a [[Astronomy:Two-stage-to-orbit|two-stage-to-orbit]] system. [[Company:SpaceX|SpaceX]], with their [[Engineering:SpaceX Starship|SpaceX Starship]], has been in development since 2016 and is aiming to make an initial test flight of a part of the system capabilities as early as 2021.<ref name=sfn20210513>{{cite news |last=Clark |first=Stephen |title=SpaceX outlines plans for Starship orbital test flight |url=https://spaceflightnow.com/2021/05/13/spacex-outlines-plans-for-around-the-world-starship-test-flight/ |work=Spaceflight Now |date=13 May 2021 |access-date=31 July 2021 |archive-date=14 May 2021 |archive-url=https://web.archive.org/web/20210514183803/https://spaceflightnow.com/2021/05/13/spacex-outlines-plans-for-around-the-world-starship-test-flight/ |url-status=live }}</ref> [[Company:Relativity Space|Relativity Space]], with their Terran R beginning development by 2021, is aiming to make an initial orbital launch test by 2024.<ref name=cnbc20210225>{{cite news |last=Sheetz |first=Michael |url=https://www.cnbc.com/2021/02/25/relativitys-reusable-terran-rocket-competitor-to-spacexs-falcon-9.html |title=Relativity Space unveils a reusable, 3D-printed rocket to compete with SpaceX's Falcon 9 |work={{wipe|CNBC}} |date=25 February 2021 |access-date=31 July 2021 |archive-date=25 February 2021 |archive-url=https://web.archive.org/web/20210225201826/https://www.cnbc.com/2021/02/25/relativitys-reusable-terran-rocket-competitor-to-spacexs-falcon-9.html |url-status=live }}</ref><ref name=ars20210608>{{cite news |last=Berger |first=Eric |title=Relativity has a bold plan to take on SpaceX, and investors are buying it |work=[[Ars Technica]] |url=https://arstechnica.com/science/2021/06/relativity-has-a-bold-plan-to-take-on-spacex-and-investors-are-buying-it/ |date=8 June 2021 |access-date=31 July 2021 |archive-date=8 June 2021 |archive-url=https://web.archive.org/web/20210608175325/https://arstechnica.com/science/2021/06/relativity-has-a-bold-plan-to-take-on-spacex-and-investors-are-buying-it/ |url-status=live }}</ref> [[Company:Blue Origin|Blue Origin]], with Project Jarvis, began development work by early 2021, but has announced no date for testing, nor even been public with their plans.<ref name=ars20210727>{{cite news |title=Blue Origin has a secret project named “Jarvis” to compete with SpaceX |url=https://arstechnica.com/science/2021/07/blue-origin-is-developing-reusable-second-stage-other-advanced-projects/ |last=Berger |first=Eric |work=[[Ars Technica]] |date=27 July 2021 |access-date=31 July 2021 |archive-date=30 July 2021 |archive-url=https://web.archive.org/web/20210730113522/https://arstechnica.com/science/2021/07/blue-origin-is-developing-reusable-second-stage-other-advanced-projects/ |url-status=live }}</ref>

Earlier plans to run tests of enhanced reusability on the second stage of the SpaceX [[Engineering:Falcon 9|Falcon 9]] were set aside in 2018.

=== Partially-reusable launch systems ===
Partial reusable launch systems, in the form of multiple stage to orbit systems have been so far the only reusable configurations in use.

=== Liftoff stages ===
Existing reusable launch systems use rocket-propelled vertical [[Engineering:Takeoff|liftoff]].{{update after|2021|7|31}}<!-- no longer correct, since [[Company:Virgin Galactic|Virgin Galactic]] began flying people on [[Engineering:SpaceShipTwo|SpaceShipTwo]] in short suborbital flights in July 2021 -->

Other than that a range of non-rocket liftoff systems have been proposed and explored over time as reusable systems for liftoff, from balloons<ref>{{cite journal|last1=Reyes|first1=Tim|title=Balloon launcher Zero2Infinity Sets Its Sights to the Stars|journal=Universe Today|date=October 17, 2014|url=http://www.universetoday.com/115391/balloon-launcher-zero2infinity-sets-its-sights-to-the-stars/|access-date=9 July 2015|archive-date=13 April 2020|archive-url=https://web.archive.org/web/20200413123411/http://www.universetoday.com/115391/balloon-launcher-zero2infinity-sets-its-sights-to-the-stars/|url-status=live}}</ref>{{relevance inline|date=October 2020}}<!-- it is unclear about how this space launch technology relates to ''reusable'' launch vehicles.  No work seems to be going on to build/test any "non-rocket spacelaunch" technologies to survive atmospheric reentry and thus become reusable. --> to [[Astronomy:Space elevator|space elevator]]s. Existing examples are systems which employ winged horizontal jet-engine powered liftoff. Such aircraft can [[Engineering:Air launch|air launch]] expendable rockets and can because of that be considered partially reusable systems if the aircraft is thought of as the first stage of the launch vehicle. An example of this configuration is the [[Engineering:Pegasus (rocket)|Orbital Sciences Pegasus]]. For suborbital flight the [[Engineering:SpaceShipTwo|SpaceShipTwo]] uses for liftoff a carrier plane, its mothership the [[Astronomy:Scaled Composites White Knight Two|Scaled Composites White Knight Two]].

=== Orbital insertion stages ===
So far, launch systems achieve orbital insertion with multistaged rockets, particularly with the second and third stages. Only the [[Engineering:Space Shuttle|Space Shuttle]] has achieved a partial reuse of the orbital insertion stage, by using the engines of [[Engineering:Space Shuttle orbiter|its orbiter]].

=== Reusable orbiter ===
{{Main|Engineering:Reusable spacecraft}}
Launch systems can be combined with reusable orbiters. The [[Engineering:Space Shuttle orbiter|Space Shuttle orbiter]], [[Engineering:SpaceShipTwo|SpaceShipTwo]] and the under-development Indian [[Astronomy:RLV-TD|RLV-TD]] are examples for a reusable space vehicle (a [[Astronomy:Spaceplane|spaceplane]]) as well as a part of its launch system.

More contemporarily the [[Engineering:Falcon 9|Falcon 9]] launch system has carried reusable vehicles such as the [[Engineering:SpaceX Dragon 2|Dragon 2]] and [[Astronomy:Boeing X-37|X-37]], transporting two reusable vehicles at the same time.

Contemporary reusable orbital vehicles include the X-37, the Dream Chaser, the Dragon 2, the Indian RLV-TD and the upcoming European [[Engineering:Space Rider|Space Rider]] (successor to the [[Astronomy:Intermediate eXperimental Vehicle|IXV]]).

As with launch vehicles, all pure spacecraft during the early decades of human capacity to achieve spaceflight<!-- late 1950s through early 2010s --> were designed to be single-use items.  This was true both for [[Astronomy:Satellite|satellite]]s and space probes intended to be left in space for a long time, as well as any object designed to return to Earth such as [[Astronomy:Human spaceflight|human-carrying]] [[Engineering:Space capsule|space capsule]]s or the sample return canisters of space matter collection missions like [[Engineering:Stardust (spacecraft)|Stardust]] (1999–2006)<ref name=newscientist20060115>{{cite news |url=https://www.newscientist.com/article/dn8586-pinch-of-comet-dust-lands-safely-on-earth/ |title=Pinch of comet dust lands safely on Earth |work=New Scientist |first=Hazel |last=Muir |date=15 January 2006 |access-date=20 January 2018 |archive-date=21 January 2018 |archive-url=https://web.archive.org/web/20180121184644/https://www.newscientist.com/article/dn8586-pinch-of-comet-dust-lands-safely-on-earth/ |url-status=live }}</ref> or [[Astronomy:Hayabusa|Hayabusa]] (2005–2010).<ref name=indyposted201006>{{Cite web|url=http://indyposted.com/27014/mission-accomplished-for-japans-asteroid-explorer-hayabusa/|archiveurl=https://web.archive.org/web/20100616232222/http://indyposted.com/27014/mission-accomplished-for-japans-asteroid-explorer-hayabusa/|url-status=dead|title=Mission Accomplished For Japan's Asteroid Explorer Hayabusa|archivedate=June 16, 2010}}</ref><ref name=sdc20100613>{{cite news |url=http://www.space.com/missionlaunches/hayabusa-asteroid-probe-landing-preview-100613.html |title=Space Probe, Perhaps with a Chunk of Asteroid, Returns to Earth Sunday |work=Space.com |date=13 June 2010 |access-date=13 June 2010 |url-status=dead |archive-url=https://web.archive.org/web/20100616062115/http://www.space.com/missionlaunches/hayabusa-asteroid-probe-landing-preview-100613.html |archive-date=16 June 2010 }}</ref>  Exceptions to the general rule for space vehicles were the US [[Engineering:Gemini SC-2|Gemini SC-2]], the [[Place:Soviet Union|Soviet Union]] spacecraft [[Astronomy:VA spacecraft|Vozvraschaemyi Apparat (VA)]], the US [[Engineering:Space Shuttle orbiter|Space Shuttle orbiter]] (mid-1970s-2011, with 135 flights between 1981 and 2011) and the Soviet [[Engineering:Buran (spacecraft)|Buran]] (1980-1988, with just one uncrewed test flight in 1988).  Both of these spaceships were also an integral part of the launch system (providing launch acceleration) as well as operating as medium-duration spaceships in [[Engineering:Orbital spaceflight|space]].  This began to change in the mid-2010s.

In the 2010s, the [[Astronomy:Commercial Resupply Services|space transport cargo capsule]] from one of the suppliers resupplying the [[Astronomy:International Space Station|International Space Station]] was designed for reuse, and after 2017,<ref name="Dragon_reused">{{cite web|url=https://spaceflightnow.com/2017/06/03/cargo-manifest-for-spacexs-11th-resupply-mission-to-the-space-station/|title=Cargo manifest for SpaceX's 11th resupply mission to the space station|publisher=Spaceflight Now|last=Clark|first=Stephen|access-date=3 June 2017|archive-date=9 August 2018|archive-url=https://web.archive.org/web/20180809111921/https://spaceflightnow.com/2017/06/03/cargo-manifest-for-spacexs-11th-resupply-mission-to-the-space-station/|url-status=live}}</ref> NASA began to allow the reuse of the SpaceX Dragon cargo spacecraft on these NASA-contracted transport routes. This was the beginning of design and operation of a '''reusable space vehicle'''<!-- bolded per WP:MOSBOLD as a redirect target -->.

Since then also the [[Engineering:Boeing Starliner|Boeing Starliner]] capsules reduce their fall speed with parachutes and deploy an airbag shortly before touchdown on the ground, in order to retrieve and reuse the vehicle.

{{asof|2020}}, SpaceX is currently building and testing the [[Engineering:SpaceX Starship|Starship]] spaceship to be capable of surviving multiple [[Physics:Hypersonic|hypersonic]] reentries through the atmosphere so that they become truly reusable long-duration spaceships; no Starship operational flights have yet occurred.

==Entry systems==
{{Main|Astronomy:Atmospheric entry}}

=== Heat shield ===
With possible inflatable [[Astronomy:Heat shield#Spacecraft|heat shield]]s, as developed by the US (Low Earth Orbit Flight Test Inflatable Decelerator - LOFTID)<ref name="noaa-20190703">{{cite web |last=Marder |first=Jenny |url=https://www.jpss.noaa.gov/news.html?122 |title=Inflatable Decelerator Will Hitch a Ride on the JPSS-2 Satellite |publisher=NOAA |date=3 July 2019 |access-date=30 October 2019}}</ref> and China,<ref>{{cite web|url=http://www.xinhuanet.com/2020-05/05/c_1125945037.htm|title="胖五"家族迎新 送新一代载人飞船试验船升空——长征五号B运载火箭首飞三大看点 (LM5 Family in focus: next generation crewed spacecraft and other highlight of the Long March 5B maiden flight)|language=zh|website=Xinhua News|author=Xinhua Editorial Board|date=5 May 2020|access-date=29 October 2020|archive-date=7 August 2020|archive-url=https://web.archive.org/web/20200807093711/http://www.xinhuanet.com/2020-05/05/c_1125945037.htm|url-status=live}}</ref> single-use rockets like the [[Astronomy:Space Launch System|Space Launch System]] are considered to be retrofitted with such heat shields to salvage the expensive engines, possibly reducing the costs of launches significantly.<ref>{{cite web |url=https://westeastspace.com/2020/05/07/is-chinas-inflatable-space-tech-a-400-million-cost-savings-for-nasas-sls/ |date=7 May 2020 |access-date=29 October 2020 |website=westeastspace.com |author=Bill D'Zio |title=Is China's inflatable space tech a $400 Million Cost savings for NASA's SLS? |archive-date=10 May 2020 |archive-url=https://web.archive.org/web/20200510233336/https://westeastspace.com/2020/05/07/is-chinas-inflatable-space-tech-a-400-million-cost-savings-for-nasas-sls/ |url-status=live }}</ref>

=== Retrograde thrust ===
{{Main||Engineering:Retrorocket|Engineering:Thrust reversal}}
Launch systems like the [[Engineering:Falcon 9|Falcon 9]] employ for their reusable stages not only at landing retrograde burns, but also at re-entry and even for boostback burns instead of only aiming for landing [[Engineering:Downrange|downrange]].

==Landing systems==
Reusable systems can come in [[Astronomy:Single-stage-to-orbit|single]] or multiple 
([[Astronomy:Two-stage-to-orbit|two]] or [[Astronomy:Three-stage-to-orbit|three]]) stages to orbit configurations. For some or all stages the following landing system types can be employed.

===Types===
====Braking====
These are landing systems that employ parachutes and bolstered hard landings, like in a [[Engineering:Splashdown|splashdown]] at sea or a touchdown at land.

Though such systems have been in use since the beginning of [[Earth:Astronautics|astronautics]] to recover space vehicles, particularly crewed [[Engineering:Space capsule|space capsule]]s, only later have the vehicles been reused.

E.g.:
*Space Shuttle Solid Rocket Boosters
*Space Shuttle growth study [[Engineering:Studied Space Shuttle designs#Recoverable Liquid Booster|recoverable liquid boosters]]

====Horizontal (winged)====
{{Main|Astronomy:Spaceplane}}
Single or main stages, as well as fly-back boosters can employ a horizontal landing system.

Examples are:
*[[Engineering:Space Shuttle orbiter|Space Shuttle orbiter]] - as part of the main stage
*Venturestar - a project of [[Organization:NASA|NASA]]
*[[Engineering:Studied Space Shuttle designs#Liquid Fly-back Booster|Space Shuttle's studied fly-back booster]]
*Energia II ("Uragan") - an alternative [[Engineering:Buran (spacecraft)|Buran]] launch system concept
*[[Engineering:OK-GLI|OK-GLI]] - another [[Engineering:Buran (spacecraft)|Buran]] spacecraft version
*Liquid Fly-back Booster - a German concept
*[[Engineering:Baikal (rocket booster)|Baikal]] - a former Russian project
*Reusable Booster System - an U.S. research project 
*[[Engineering:SpaceShipTwo|SpaceShipTwo]] or [[Astronomy:VSS Unity|VSS Unity]] - an [[Astronomy:Spaceplane|Spaceplane]] of Space Tourism made by [[Company:Virgin Galactic|Virgin Galactic]] 
*[[Astronomy:SpaceShipThree|SpaceShipThree]] or [[Engineering:VSS Imagine|VSS Imagine]] - another [[Astronomy:Spaceplane|Spaceplane]] of Space Tourism made by [[Company:Virgin Galactic|Virgin Galactic]] 
*[[Engineering:XS-1 (spacecraft)|XS-1]] - another U.S. research project
*[[Astronomy:RLV-TD|RLV-TD]] - an ongoing Indian project
*[[Company:Reaction Engines|Reaction Engines]] [[Engineering:Skylon (spacecraft)|Skylon]] SSTO
A variant is an in-air-capture tow back system, advocated by a company called EMBENTION with its FALCon project.<ref>{{cite web |url=https://www.embention.com/project/falcon-project/ |access-date=29 October 2020 |title=FALCon |website=embention.com |archive-date=27 October 2020 |archive-url=https://web.archive.org/web/20201027121718/https://www.embention.com/project/falcon-project/ |url-status=live }}</ref>

Vehicles that land horizontally on a runway require wings and undercarriage. These typically consume about 9-12% of the landing vehicle mass,{{citation needed|date=July 2020}} which either reduces the payload or increases the size of the vehicle. Concepts such as [[Engineering:Lifting body|lifting bodies]] offer some reduction in wing mass,{{citation needed|date=July 2020}} as does the [[Engineering:Delta wing|delta wing]] shape of the [[Engineering:Space Shuttle|Space Shuttle]].

====Vertical (retrograde)====
{{Main|Engineering:VTVL|Engineering:Retrorocket|Engineering:Thrust reversal}}
Systems like the [[Engineering:McDonnell Douglas DC-X|McDonnell Douglas DC-X (Delta Clipper)]] and those by [[Company:SpaceX|SpaceX]] are examples of a retrograde system.
The boosters of [[Engineering:Falcon 9|Falcon 9]] and [[Engineering:Falcon Heavy|Falcon Heavy]] land using one of their nine engines. The [[Engineering:Falcon 9|Falcon 9]] rocket is the first orbital rocket to vertically land its first stage on the ground. Both stages of [[Engineering:SpaceX Starship|Starship]] are planned to land vertically.

Retrograde landing typically requires about 10% of the total first stage propellant, reducing the payload that can be carried due to the rocket equation.<ref>{{cite web|url=https://twitter.com/SpaceX/status/679114269485436928|title=SpaceX on Twitter|work=Twitter|access-date=January 7, 2016|archive-date=September 20, 2020|archive-url=https://web.archive.org/web/20200920110637/https://twitter.com/SpaceX/status/679114269485436928|url-status=live}}</ref>

====Landing using aerostatic force====
There is also the concept of a launch vehicle with an inflatable, reusable first stage. The shape of this structure will be supported by excess internal pressure (using light gases). It is assumed that the bulk density of the first stage (without propellant) is less than the bulk density of air. Upon returning from flight, such a first stage remains floating in the air (without touching the surface of the Earth). This will ensure that the first stage is retained for reuse. Increasing the size of the first stage increases aerodynamic losses. This results in a slight decrease in payload. This reduction in payload is compensated for by the reuse of the first stage. <ref>{{Citation |url = https://engrxiv.org/xbf8z/ |first1 = Valentyn |last1 = Pidvysotskyi |title = The Concept of an Inflatable Reusable Launch Vehicle |date = July 2021 |access-date = 2021-08-18 |archive-date = 2021-08-18 |archive-url = https://web.archive.org/web/20210818223109/https://engrxiv.org/xbf8z/ |url-status = live }}</ref>

== Constraints ==
=== Extra weight ===
Reusable stages weigh more than equivalent expendable stages. This is unavoidable due to the supplementary systems, landing gear and/or surplus propellant needed to land a stage. The actual mass penalty depends on the vehicle and the return mode chosen.<ref name=IAC2017 >{{Citation | url = http://elib.dlr.de/114960/1/IAC17-D2.4.4.pdf | first1 = M | last1 = Sippel | first2 = S | last2 = Stappert | first3 = L | last3 = Bussler | first4 = E | last4 = Dumont | title = Systematic Assessment of Reusable First-Stage Return Options | journal = IAC-17-D2.4.4, 68th International Astronautical Congress, Adelaide, Australia. | date = September 2017 | access-date = 2017-12-26 | archive-date = 2020-04-13 | archive-url = https://web.archive.org/web/20200413165634/https://elib.dlr.de/114960/1/IAC17-D2.4.4.pdf | url-status = live }}</ref>

===Refurbishment===
After the launcher lands, it may need to be refurbished to prepare it for its next flight. This process may be lengthy and expensive. The launcher may not be able to be recertified as human-rated after refurbishment, although SpaceX has flown reused Falcon 9 boosters for human missions. There is eventually a limit on how many times a launcher can be refurbished before it has to be retired, but how often a spacecraft can be reused differs significantly between the various launch system designs.

==History==
With the development of [[Engineering:Rocket propulsion|rocket propulsion]] in the first half of the twentieth century, [[Engineering:Spaceflight|space travel]] became a technical possibility.

Early ideas of a single-stage reusable [[Astronomy:Spaceplane|spaceplane]] proved unrealistic and although even the first practical rocket vehicles (V-2) could reach the fringes of space, reusable technology was too heavy. In addition many early rockets were developed to deliver weapons, making reuse impossible by design. The problem of mass efficiency was overcome by using multiple expendable stages in a vertical-launch [[Astronomy:Multistage rocket|multistage rocket]]. USAF and NACA had been studying orbital reusable spaceplanes since 1958, e.g. Dyna-Soar, but the first reusable stages did not fly until the advent of the US [[Engineering:Space Shuttle|Space Shuttle]] in 1981.

===20th century===
[[File:McDonnell Douglas DC-XA.jpg|thumb|right|[[Engineering:McDonnell Douglas DC-X|McDonnell Douglas DC-X]] used vertical takeoff and vertical landing]]

Perhaps the first reusable launch vehicles were the ones conceptualized and studied by [[Biography:Wernher von Braun|Wernher von Braun]] from 1948 until 1956. The Von Braun Ferry Rocket underwent two revisions: once in 1952 and again in 1956. They would have landed using parachutes.<ref>{{Cite web|url=http://www.astronautix.com/v/vonbraunconceptvehicle.html|title=von Braun concept vehicle|website=www.astronautix.com|access-date=2020-11-15|archive-date=2020-11-12|archive-url=https://web.archive.org/web/20201112012312/http://www.astronautix.com/v/vonbraunconceptvehicle.html|url-status=live}}</ref><ref>{{Cite web|url=https://www.wired.com/2014/09/wernher-von-brauns-fantastic-vision-ferry-rocket/|title=Wernher von Braun's Fantastic Vision: Ferry Rocket &#124; WIRED|via=www.wired.com|access-date=2020-11-15|archive-date=2020-11-12|archive-url=https://web.archive.org/web/20201112024915/https://www.wired.com/2014/09/wernher-von-brauns-fantastic-vision-ferry-rocket/|url-status=live}}</ref>

The [[Engineering:General Dynamics Nexus|General Dynamics Nexus]] was proposed in the 1960s as a fully reusable successor to the Saturn V rocket, having the capacity of transporting up to {{cvt|990000-2000000|lb|t|order=flip}} to orbit.<ref>{{Cite web|url=https://history.nasa.gov/SP-4221/ch2.htm|title=ch2|website=history.nasa.gov}}</ref><ref>{{Cite web|url=http://www.astronautix.com/n/nexus.html|title=Nexus|website=www.astronautix.com|access-date=2020-11-15|archive-date=2020-11-09|archive-url=https://web.archive.org/web/20201109032934/http://www.astronautix.com/n/nexus.html|url-status=live}}</ref> See also [[Engineering:Sea Dragon (rocket)|Sea Dragon]], and Douglas SASSTO.

The [[Engineering:BAC Mustard|BAC Mustard]] was studied starting in 1964. It would have comprised three identical spaceplanes strapped together and arranged in two stages. During ascent the two outer spaceplanes, which formed the first stage, would detach and glide back individually to earth. It was canceled after the last study of the design in 1967 due to a lack of funds for development.<ref>{{Cite web|url=https://www.baesystems.com/en-uk/feature/1960s-lsquothunderbirdsrsquo-projects-brought-to-life|title=Forgotten 1960s ‘Thunderbirds’ projects brought to life|website=BAE Systems &#124; United Kingdom|access-date=2021-02-07|archive-date=2021-01-18|archive-url=https://web.archive.org/web/20210118141419/https://www.baesystems.com/en-uk/feature/1960s-lsquothunderbirdsrsquo-projects-brought-to-life|url-status=live}}</ref>

NASA started the [[Engineering:Space Shuttle design process|Space Shuttle design process]] in 1968, with the vision of creating a fully reusable [[Astronomy:Spaceplane|spaceplane]] using a crewed fly-back booster. This concept proved expensive and complex, therefore the design was scaled back to reusable solid rocket boosters and an expendable external tank.<ref name=nasaStudy1982>[https://web.archive.org/web/20100513080246/https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19940004970_1994004970.pdf NASA-CR-195281, "Utilization of the external tanks of the space transportation system"]</ref><ref name=nasaStudy1980>{{cite web|url=http://www.astronautix.com/craft/stsation.htm|title=STS External Tank Station|publisher=Ntrs.nasa.gov|access-date=7 January 2015|url-status=dead|archive-url=https://web.archive.org/web/20150407010201/http://www.astronautix.com/craft/stsation.htm|archive-date=7 April 2015}}</ref> Space Shuttle ''[[Engineering:Space Shuttle Columbia|Columbia]]'' launched and landed 27 times and was lost with all crew on the 28th landing attempt; ''[[Engineering:Space Shuttle Challenger|Challenger]]''
launched and landed 9 times and was lost with all crew on the 10th launch attempt; ''[[Engineering:Space Shuttle Discovery|Discovery]]'' launched and landed 39 times; ''[[Engineering:Space Shuttle Atlantis|Atlantis]]'' launched and landed 33 times.

In 1986 President Ronald Reagan called for an air-breathing [[Astronomy:Scramjet|scramjet]] National Aerospace Plane (NASP)/X-30. The project failed due to technical issues and was canceled in 1993.<ref>{{Cite web|url=http://www.astronautix.com/c/coppercanyon.html|title=Copper Canyon|website=www.astronautix.com|access-date=2018-06-08|archive-date=2020-09-20|archive-url=https://web.archive.org/web/20200920050424/http://www.astronautix.com/c/coppercanyon.html|url-status=live}}</ref>

In the late 1980s a fully reusable version of the Energia rocket, the Energia II, was proposed. Its boosters and core would have had the capability of landing separately on a runway.<ref>{{Cite web|url=http://www.buran.ru/htm/41-3.htm|title=Б.И.Губанов. Триумф и трагедия "Энергии" глава 41|website=www.buran.ru|access-date=2020-11-14|archive-date=2020-11-08|archive-url=https://web.archive.org/web/20201108103946/http://www.buran.ru/htm/41-3.htm|url-status=live}}</ref>

In the 1990s the [[Company:McDonnell Douglas|McDonnell Douglas]] Delta Clipper VTOL SSTO proposal progressed to the testing phase. The DC-X prototype demonstrated rapid turnaround time and automatic computer control.

In mid-1990s, British research evolved an earlier [[Engineering:HOTOL|HOTOL]] design into the far more promising [[Engineering:Skylon (spacecraft)|Skylon]] design, which remains in development.

From the late 1990s to the 2000s, the [[Organization:European Space Agency|European Space Agency]] studied the recovery of the [[Engineering:Ariane 5|Ariane 5]] solid rocket boosters.<ref>{{Cite web|url=https://www.esa.int/ESA_Multimedia/Images/2008/11/Recovery_of_an_Ariane_5_booster_at_sea|title=Recovery of an Ariane 5 booster at sea|website=www.esa.int|access-date=2021-03-03|archive-date=2021-10-01|archive-url=https://web.archive.org/web/20211001025526/https://www.esa.int/ESA_Multimedia/Images/2008/11/Recovery_of_an_Ariane_5_booster_at_sea|url-status=live}}</ref> The last recovery attempt took place in 2009.<ref>{{Cite web|url=http://www.france-science.org/spip.php?article399#3-ARIANE-5-ECA-BOOSTER-RECOVERED|archive-url=https://web.archive.org/web/20090125213207/http://www.france-science.org/spip.php?article399#3-ARIANE-5-ECA-BOOSTER-RECOVERED|url-status=dead|archive-date=2009-01-25|title=France in Space #387|website=www.web.archive.org|access-date=2021-03-03}}</ref>

The commercial ventures, [[Company:Rocketplane Kistler|Rocketplane Kistler]] and Rotary Rocket, attempted to build reusable privately developed rockets before going bankrupt.{{citation needed|date=January 2021}}

NASA proposed reusable concepts to replace the Shuttle technology, to be demonstrated under the X-33 and X-34 programs, which were both cancelled in the early 2000s due to rising costs and technical issues.

=== 21st century ===
[[File:Kluft-photo-SS1-landing-June-2004-Img 1406c.jpg|thumb|Scaled Composites SpaceShipOne used horizontal landing after being launched from a carrier airplane|alt=]]
[[File:Falcon Heavy Side Boosters landing on LZ1 and LZ2 - 2018 (25254688767).jpg|right|thumb|330x330px|Falcon Heavy side boosters landing during 2018 demonstration mission.]]
The Ansari X Prize contest was intended to develop private suborbital reusable vehicles. Many private companies competed, with the winner, [[Company:Scaled Composites|Scaled Composites]], reaching the [[Earth:Kármán line|Kármán line]] twice in a two-week period with their reusable [[Engineering:SpaceShipOne|SpaceShipOne]].

In 2012, [[Company:SpaceX|SpaceX]] started a flight test program with [[Engineering:Grasshopper (rocket)|experimental vehicles]]. These subsequently led to the development of the [[Engineering:Falcon 9|Falcon 9]] reusable rocket launcher.<ref name="nsw20130328">{{cite news|url=http://www.newspacewatch.com/articles/spacex-moving-quickly-towards-fly-back-first-stage.html|title=SpaceX moving quickly towards fly-back first stage|last=Lindsey|first=Clark|date=2013-03-28|newspaper=NewSpace Watch|access-date=2013-03-29|url-access=subscription|archive-date=2013-04-16|archive-url=https://web.archive.org/web/20130416030256/http://www.newspacewatch.com/articles/spacex-moving-quickly-towards-fly-back-first-stage.html|url-status=live}}</ref>

On 23 November 2015 the [[Astronomy:New Shepard|New Shepard]] rocket became the first [[Engineering:VTVL|Vertical Take-off, Vertical Landing]] (VTVL)<!-- VTVL is used in rocketry; "[[Engineering:VTOL|VTOL]]" is a term used in aviation with aeroplanes --> sub-orbital rocket to reach space by passing the [[Earth:Kármán line|Kármán line]] ({{cvt|100|km|disp=or}}), reaching {{cvt|329,839|ft}} before returning for a propulsive landing.<ref name="space20151124">{{cite news |url=http://www.space.com/31202-blue-origin-historic-private-rocket-landing.html |title=Blue Origin Makes Historic Reusable Rocket Landing in Epic Test Flight |work=Calla Cofield |publisher=Space.Com |date=2015-11-24 |access-date=2015-11-25 |archive-date=2021-02-09 |archive-url=https://web.archive.org/web/20210209034257/https://www.space.com/31202-blue-origin-historic-private-rocket-landing.html |url-status=live }}</ref><ref name="arstechnica20151125">{{cite web|last1=Berger|first1=Eric|title=Jeff Bezos and Elon Musk spar over gravity of Blue Origin rocket landing|url=https://arstechnica.com/science/2015/11/jeff-bezos-and-elon-musk-spar-over-gravity-of-blue-origin-rocket-landing/|website=Ars Technica|access-date=25 November 2015|archive-date=13 April 2020|archive-url=https://web.archive.org/web/20200413123413/https://arstechnica.com/science/2015/11/jeff-bezos-and-elon-musk-spar-over-gravity-of-blue-origin-rocket-landing/|url-status=live}}</ref>

SpaceX achieved the first vertical soft landing of a reusable orbital rocket stage on December 21, 2015, after delivering 11 [[Engineering:Orbcomm OG-2|Orbcomm OG-2]] commercial satellites into [[Astronomy:Low Earth orbit|low Earth orbit]].<ref>{{cite web|url=https://twitter.com/SpaceX/status/679114269485436928|title=SpaceX on Twitter|work=Twitter|access-date=2015-12-22|archive-date=2020-09-20|archive-url=https://web.archive.org/web/20200920110637/https://twitter.com/SpaceX/status/679114269485436928|url-status=live}}</ref>

The first reuse of a Falcon 9 first stage occurred on 30 March 2017.<ref>{{cite news|url=https://www.theguardian.com/science/video/2017/mar/31/spacex-successfuly-launches-first-recycled-rocket-video|title=SpaceX {{sic|nolink=y|reason=error in source|suc|cessful|y}} launches first recycled rocket – video|date=31 March 2017|agency=Reuters|work=The Guardian|access-date=31 March 2017|archive-date=9 February 2021|archive-url=https://web.archive.org/web/20210209034302/https://www.theguardian.com/science/video/2017/mar/31/spacex-successfuly-launches-first-recycled-rocket-video|url-status=live}}</ref> SpaceX now semi-routinely recovers and reuses [[Engineering:SpaceX reusable launch system development program#Fairing reuse|their first stages, as well as reusing fairings]].<ref>{{Cite web|url=https://www.space.com/spacex-reuse-payload-fairing-starlink-launch.html|title=SpaceX Recovered Falcon Heavy Nose Cone, Plans to Re-fly it This Year (Photos)|first=Mike Wall 12|last=April 2019|website=Space.com|access-date=2019-04-29|archive-date=2021-02-09|archive-url=https://web.archive.org/web/20210209040053/https://www.space.com/spacex-reuse-payload-fairing-starlink-launch.html|url-status=live}}</ref>

In 2019 [[Company:Rocket Lab|Rocket Lab]] announced plans to recover and reuse the first stage of their [[Engineering:Electron (rocket)|Electron]] launch vehicle, intending to use [[Engineering:Parachute|parachute]]s and mid-air retrieval.<ref name=rlab20190806>{{cite web|url=https://www.rocketlabusa.com/about-us/updates/rocket-lab-announces-reusability-plans-for-electron-rocket/|title=Rocket Lab Announces Reusability Plans For Electron Rocket|publisher=Rocket Lab|date=6 August 2019|access-date=7 December 2019|archive-date=21 May 2021|archive-url=https://web.archive.org/web/20210521172157/https://www.rocketlabusa.com/about-us/updates/rocket-lab-announces-reusability-plans-for-electron-rocket/|url-status=live}}</ref> On 20 November 2020, Rocket Lab successfully returned an Electron first stage from an orbital launch, the stage softly splashing down in the Pacific Ocean.<ref name="SpaceNews 2020">{{cite web | title=Rocket Lab launches Electron in test of booster recovery | website=SpaceNews | date=2020-11-20 | url=https://spacenews.com/rocket-lab-launches-electron-in-test-of-booster-recovery/ | access-date=2020-11-20 | archive-date=2021-10-01 | archive-url=https://web.archive.org/web/20211001025441/https://spacenews.com/rocket-lab-launches-electron-in-test-of-booster-recovery/ | url-status=live }}</ref>

China is researching the reusability of the [[Engineering:Long March 8|Long March 8]] system.<ref>{{cite web|url=https://spacenews.com/china-to-test-rocket-reusability-with-planned-long-march-8-launcher/|title=China to test rocket reusability with planned Long March 8 launcher|date=2018-04-30|publisher=SpaceNews.com|access-date=2020-10-04|archive-date=2021-10-01|archive-url=https://web.archive.org/web/20211001025442/https://spacenews.com/china-to-test-rocket-reusability-with-planned-long-march-8-launcher/|url-status=live}}</ref>

{{As of|May 2020}}, the only operational reusable orbital-class launch systems are the Falcon 9 and [[Engineering:Falcon Heavy|Falcon Heavy]], the latter of which is based upon the Falcon 9. SpaceX is also developing the fully-reusable [[Engineering:SpaceX Starship|Starship]] launch system,<ref name=musk20170929>
{{cite AV media |url=https://www.youtube.com/watch?v=tdUX3ypDVwI |people=Elon Musk |title=Becoming a Multiplanet Species |date=29 September 2017 |medium=video |location=68th annual meeting of the International Astronautical Congress in Adelaide, Australia |publisher=SpaceX |via=YouTube |access-date=2017-12-31}}</ref> and [[Company:Blue Origin|Blue Origin]] is developing its own [[Astronomy:New Glenn|New Glenn]] partially-reusable orbital rocket, as it is intending to recover and reuse only the first stage.

5 October 2020, Roscosmos signed a development contract for [[Engineering:Amur (launch vehicle)|Amur]] a new launcher with a reusable first stage.<ref name=roscosmos20201005>{{cite web |title=Trouble-free as a Kalashnikov assault rifle: the Amur methane rocket |url=https://www.roscosmos.ru/29357/ |publisher=[[Company:Roscosmos|Roscosmos]] |language=ru |date=5 October 2020 |access-date=6 October 2020 |archive-date=6 October 2020 |archive-url=https://web.archive.org/web/20201006120801/https://www.roscosmos.ru/29357/ |url-status=live }}</ref>

In December 2020, ESA signed contracts to start developing THEMIS, a prototype reusable first stage launcher.<ref>{{Cite web|url=https://www.spacedaily.com/reports/ESA_plans_demonstration_of_a_reusable_rocket_stage_999.html|title=ESA plans demonstration of a reusable rocket stage|website=Space Daily|access-date=2020-12-19|archive-date=2020-12-16|archive-url=https://web.archive.org/web/20201216090722/https://www.spacedaily.com/reports/ESA_plans_demonstration_of_a_reusable_rocket_stage_999.html|url-status=live}}</ref>

==List of reusable launch systems==
{{Incomplete list|date=August 2021}}
{|class="wikitable sortable"
|-
! Company !! Vehicle !! Country !! Type !! Status !! Notes
|-
| [[Company:SpaceX|SpaceX]] || [[Engineering:Falcon 9|Falcon 9]] || US || Orbital || Operational || First stage and fairing reusable.
|-
| [[Company:SpaceX|SpaceX]] || [[Engineering:Falcon Heavy|Falcon Heavy]] || US || Orbital || Operational || Core, side boosters and fairing reusable.
|-
|[[Company:SpaceX|SpaceX]]
|[[Engineering:SpaceX Starship|Starship]]
|US
|Orbital
|Prototype
|Fully reusable.
|-
| [[Company:Rocket Lab|Rocket Lab]] || [[Engineering:Electron (rocket)|Electron]]|| New Zealand || Orbital || Operational|| First stage recovered but not yet reused.
|-
| [[Company:Rocket Lab|Rocket Lab]] || Neutron|| New Zealand || Orbital || Under development || First stage reusable
|-
| [[Company:Blue Origin|Blue Origin]] || [[Astronomy:New Shepard|New Shepard]] || US || Suborbital || Operational|| Fully reusable
|-
| [[Company:Blue Origin|Blue Origin]] || [[Astronomy:New Glenn|New Glenn]] || US || Orbital || Under development|| First stage reusable
|-
| [[Company:United Launch Alliance|United Launch Alliance]] || Vulcan Centaur || US || Orbital || Under development || First stage engine module reusable in a later development.
|-
| [[Company:Virgin Galactic|Virgin Galactic]] || [[Engineering:SpaceShipTwo|SpaceShipTwo]] or [[Astronomy:VSS Unity|VSS Unity]]|| US || Suborbital || Prototype || Designed for space tourism. Fully reusable
|-
| [[Company:Virgin Galactic|Virgin Galactic]] || [[Astronomy:SpaceShipThree|SpaceShipThree]] or [[Engineering:VSS Imagine|VSS Imagine]] || US || Suborbital || Prototype || Designed for space tourism. Fully reusable
|-
| [[Organization:NASA|NASA]] || [[Engineering:Space Shuttle|Space Shuttle]] || US || Orbital ||Retired|| Orbiter and side boosters reusable
|-
| [[Company:Energia (corporation)|NPO-Energia]] || Energia-Buran or [[Engineering:OK-GLI|OK-GLI]] || USSR || Orbital ||Retired|| Only [[Engineering:Buran programme|Buran orbiter]] payload reusable; Energia launcher fully expended.
|-
|[[Astronomy:Indian Space Research Organisation|ISRO]]
|[[Astronomy:RLV-TD|RLV TSTO]]
|India
|Orbital
|Under development
|Two Stage to Orbit with initial upper stage reusability and eventual full reusability
|-
|[[Company:I-Space (Chinese company)|I-space]]
|Hyperbola-2
|China 
|Orbital
|Under development
|Prototype
|-
|[[Company:Roscosmos|Roscosmos]]
|[[Engineering:Amur (launch vehicle)|Amur]]
|Russia
|Orbital
|Under development
|Prototype
|-
|[[Organization:European Space Agency|ESA]]
|Themis
|EU
|Orbital
|Under development
|Prototype, aiming for first stage reuse
|-
|[[Company:Relativity Space|Relativity Space]]
|Terran R
|US
|Orbital
|Under development
|First fully reusable 3D printed rocket
|}

==See also==
{{div col}}
* [[Engineering:Reusable spacecraft|Reusable spacecraft]]
* [[Engineering:SpaceX reusable launch system development program|SpaceX reusable launch system development program]]
* [[Astronomy:List of private spaceflight companies|List of private spaceflight companies]]
* Takeoff and landing
*[https://mars.nasa.gov/insight/entry-descent-landing/ Mars Descent Vehicle]
*[https://mars.nasa.gov/insight/entry-descent-landing/ Mars Ascent Vehicle]
*[[Engineering:Lunar Lander (spacecraft)|Lunar Lander]]
{{div col end}}

==References==
{{Reflist|colwidth=30em}}

==Bibliography==
* Heribert Kuczera, et al.: ''Reusable space transportation systems.'' Springer, Berlin 2011, {{ISBN|978-3-540-89180-2}}.

==External links==
* [http://www.ikonet.com/en/visualdictionary/astronomy/astronautics/space-shuttle/space-shuttle-at-takeoff.php Illustration of a Space Shuttle at takeoff and Orbiter] (Visual Dictionary - QAInternational)
*[[Astronomy:Lunar lander|Lunar Lander Module]]

{{Reusable launch systems}}
{{Spaceflight}}
{{emerging technologies|topics=yes|space=yes}}
{{European launch systems}}

[[Category:Spacecraft propulsion]]
[[Category:Reusable launch systems| ]]
[[Category:Space launch vehicles]]
[[Category:Space access]]
[[Category:Rocket propulsion]]

{{Sourceattribution|Reusable launch system|1}}