Method of takeoff and landing used by rockets; Vertical Takeoff, Vertical Landing
A Falcon 9 first stage performing a vertical landingDC-XA landing in 1996
Vertical takeoff, vertical landing (VTVL) is a form of takeoff and landing for rockets. Multiple VTVL craft have flown. The most widely known and commercially successful VTVL rocket is SpaceX's Falcon 9 first stage.[citation needed]
Starting in the mid-2010s, VTVL was under intense development as a technology for reusable rockets large enough to transport people. In 2013, SpaceX demonstrated vertical landing on a Falcon 9 prototype after climbing 744 meters in the air.[1] Later, Blue Origin (New Shepard) and SpaceX (Falcon 9), both demonstrated recovery of launch vehicles after return to the launch site (RTLS) operations, with Blue Origin's New Shepard booster rocket making the first successful vertical landing on November 23, 2015, following a flight that reached outer space, and SpaceX's Falcon 9 flight 20 marking the first landing of a commercial orbital booster roughly a month later, on December 22, 2015. All but one launch of the SpaceX Falcon Heavy have included VTVL attempts for the two side boosters on each rocket. SpaceX is also developing a fully reusable rocket named Starship.[2]
VTVL rockets are not to be confused with aircraft which take off and land vertically which use the air for support and propulsion, such as helicopters and jump jets which are VTOL aircraft.
VTVL rocket concepts were studied by Philip Bono of Douglas Aircraft Co. in the 1960s.[4]
Apollo Lunar Module was a 1960s two-stage VTVL vehicle for landing and taking off from the Moon.
Australia's Defence Science and Technology Group successfully launches the Hoveroc rocket on 2 May 1981 in a test at Port Wakefield, South Australia.[5] It was capable of "a controlled flight path within a horizontal plane and terminating, if needed, in a controlled descent."[6]
The Soviet Union did some development work on, but never flew, a vertically landing crewed capsule called Zarya in the late 1980s.[7]
The McDonnell Douglas DC-X was a 1/3 scale uncrewed prototype SSTO VTVL launch vehicle that flew several successfully test flights in the 1990s. Its first successful flight was in 1993. In June 1996, the vehicle set an altitude record of 3,140 metres (10,300 ft), before making a vertical landing.[8]
Rotary Rocket successfully tested a vertical landing system for their Roton design, based around a rocket tipped helicopter system in 1999, but were unable to raise funds to build a full vehicle.
June 13, 2005 Blue Origin VTVL Suborbital Reusable Launch Vehicle was announced.[9]
2005 Blue Origin Charon a jet engine propelled test vehicle verified the autonomous guidance and control technologies later used in Blue Origins VTVL rockets.[10]
2006, 2007 Blue Origin Goddard a subscale demonstrator for the later New Shephard suborbital vehicle, made 3 successful flights before retirement.[11]
SpaceX announced plans in 2010 to eventually install deployable landing gear on the Dragon spacecraft and use the vehicle's thrusters to perform a land-based landing.[13] It was cancelled in 2017.[14]
Morpheus is a 2010s NASA project developing a vertical test bed that demonstrates new green propellant propulsion systems and autonomous landing and hazard detection technology.[16]
Mighty Eagle was an early 2010s Robotic Prototype Lander that was being developed by NASA as of August 2012.[17]
A Falcon 9 first stage landing on 21 December 2015 after boosting commercial satellites to low Earth orbit
2012: SpaceX's Grasshopper rocket was a VTVL first-stage booster test vehicle developed to validate various low-altitude, low-velocity engineering aspects of its large-vehicle reusable rocket technology.[20] The test vehicle made eight successful test[21] flights in 2012–2013. Grasshopper v1.0 made its eighth, and final, test flight on October 7, 2013, flying to an altitude of 744 metres (2,441 ft) (0.46 miles) before making its eighth successful VTVL landing.[22]
On November 23, 2015, Blue Origin's New Shepard booster rocket made the first-ever successful vertical landing following an uncrewed suborbital test flight that reached space.[26]
On December 21, 2015, SpaceX's 20th Falcon 9 first stage made the first-ever successful vertical landing of an orbital-class booster after boosting 11 commercial satellites to low Earth orbit on Falcon 9 Flight 20.[27]
Since 2017, DLR, CNES and JAXA are developing a reusable VTVL rocket demonstrator called CALLISTO (Cooperative Action Leading to Launcher Innovation in Stage Toss-back Operations).[29]
January 2018: Chinese private space company LinkSpace successfully tested its reusable experimental orbital rocket with a successful vertical takeoff, vertical landing (VTVL)[30]
2018: ISRO revealed details about the ADMIRE test vehicle for which a test and landing site was being developed. The vehicle will have supersonic retro propulsion, special retractable landing legs which will act as steerable grid fins & will be guided by integrated navigation system that will have a laser altimeter and a NavIC receiver.[32]
In August 2020, SpaceX began testing its Starship prototypes. SN5, SN6, and SN15 all made successful VTVL launch and landings while SN8, SN9, SN10, and SN11 were each destroyed due to landing failure.[36][37][33][38]
On July 20, 2021, Blue Origin's New Shepard rocket made its first-ever successful vertical landing following a crewed suborbital flight. Four passengers were on board in the mission NS-16, including Jeff Bezos.[39]
Vertical landing technology
The technology required to successfully achieve retropropulsive landings—the vertical landing or "VL" addition to the standard vertical takeoff (VT) technology of the early decades of human spaceflight—has several parts. First, thrust must be less than weight, second the thrust is normally required to be vectored and requires some degree of throttling. Guidance must be capable of calculating the position and altitude of the vehicle, small deviations from the vertical can cause large deviations of the vehicles horizontal position. RCS systems are usually required to keep the vehicle at the correct angle.
SpaceX also use grid fins for attitude control during landing of their Falcon 9 boosters.
The additional weight of fuel, larger tank, landing legs and their deployment mechanisms will usually reduce the performance of a soft landing system compared to expendable vehicles, all other things being equal.
The main benefit of the technology is seen in the potential for substantial reductions in space flight costs as a result of being able to reuse rockets after successful VTVL landings.[41]
Popular culture
Vertical landing rocket depicted in 1951 comic Rocket Ship X
Vertical landing of spaceships was the predominant mode of rocket landing envisioned in the pre-spaceflight era. Many science fiction authors as well as depictions in popular culture showed rockets landing vertically, typically resting after landing on the space vehicle's fins. This view was sufficiently ingrained in popular culture that in 1993, following a successful low-altitude test flight of a prototype rocket, a writer opined: "The DC-X launched vertically, hovered in mid-air ... The spacecraft stopped mid-air again and, as the engines throttled back, began its successful vertical landing. Just like Buck Rogers."[42]
In the 2010s, SpaceXrockets have likewise seen the appellation to this popular culture notion of Buck Rogers in a "Quest to Create a 'Buck Rogers' Reusable Rocket."[43][44]
The Young Sheldon episode, "A Patch, a Modem, and a Zantac®" features Sheldon Cooper developing the equations for VTVL in the 1980s, only to have them rejected by NASA for lack of the technical capability to implement it at that time. Sheldon concludes that he is ahead of his time. A flashforward to 2016 shows the successful SpaceX CRS-8 mission, followed by SpaceX founder Elon Musk looking over Sheldon's old notebook then hiding it in a desk drawer.[45][46][47][48]
^Wade, Mark. "OOST". Encyclopedia Astronautica. Archived from the original on 2011-10-10. Retrieved 2011-10-04.
^Crozier, Mal (2013). Nulka: A compelling story(PDF). Canberra: Defence Science and Technology Organisation. pp. 40–41. ISBN9780987544704. Archived(PDF) from the original on 2021-02-25. Retrieved 2021-03-19.
^Zak, Anatoly (2009-04-29). "Russia mulls rocket power 'first'". BBC News. Archived from the original on 2011-04-24. Retrieved 2011-10-11. RKK Energia, ... in the 1980s ... worked on a highly classified project to develop a large crewed capsule, called Zarya ("Dawn"), for a wide range of civilian and military missions.
^Klerkx, Greg: Lost in Space: The Fall of NASA and the Dream of a New Space Age, page 104. Secker & Warburg, 2004
^[needs update]"sRLV platforms compared". NASA. 2011-03-07. Archived from the original on 2021-02-20. Retrieved 2011-03-10. New Shepard which was made by the "Blue Origin"(founded by Jeff Bezos): Type: VTVL/Unpiloted ... Super Mod: Type: VTVL/Unpiloted ... Xaero: Type: VTVL/Unpiloted
^Bibby, Joe. "Project Morpheus". NASA. Archived from the original on August 29, 2012. Retrieved October 1, 2012.
^"Reusable rocket prototype almost ready for first liftoff". Spaceflight Now. 2012-07-09. Archived from the original on 2013-05-21. Retrieved 2012-07-13. SpaceX has constructed a half-acre concrete launch facility in McGregor, and the Grasshopper rocket is already standing on the pad, outfitted with four insect-like silver landing legs.
^The Grasshopper prototype test vehicle has been retired.
"Grasshopper flies to its highest height to date". Social media information release. SpaceX. 12 October 2013. Archived from the original on 17 January 2016. Retrieved 14 October 2013. WATCH: Grasshopper flies to its highest height to date – 744 m (2441 ft) into the Texas sky. http://youtu.be/9ZDkItO-0a4 This was the last scheduled test for the Grasshopper rig; next up will be low altitude tests of the Falcon 9 Reusable (F9R) development vehicle in Texas followed by high altitude testing in New Mexico.
^Norris, Guy (2014-04-28). "SpaceX Plans For Multiple Reusable Booster Tests: Controlled water landing marks a major stride toward SpaceX's Falcon rapid-reusability goal". Aviation Week. Archived from the original on 2014-04-26. Retrieved 2014-04-26. The April 17 F9R Dev 1 flight, which lasted under 1 min., was the first vertical landing test of a production-representative recoverable Falcon 9 v1.1 first stage, while the April 18 cargo flight to the ISS was the first opportunity for SpaceX to evaluate the design of foldable landing legs and upgraded thrusters that control the stage during its initial descent.
^"Restoration Center Open House Highlights". New Mexico Museum of Space History. 2013-02-12. Archived from the original on 2014-03-24. Retrieved 2014-03-24. The DC-X launched vertically, hovered in mid-air at 150 feet, and began to move sideways at a dogtrot. After traveling 350 feet, the onboard global-positioning satellite unit indicated that the DC-X was directly over its landing point. The spacecraft stopped mid-air again and, as the engines throttled back, began its successful vertical landing. Just like Buck Rogers.
^Elon Musk, Scott Pelley (2014-03-30). Tesla and SpaceX: Elon Musk's industrial empire (video and transcript). CBS. Event occurs at 03:50–04:10. Retrieved 2014-03-31. Only four entities have launched a space capsule into orbit and successfully brought it back: the United States, Russia, China, and Elon Musk. This Buck Rogers dream started years ago...