VTVL

Pixel is a Quad that took off and landed vertically

DC-XA landing in 1996

Vertical takeoff, vertical landing (VTVL) is a form of takeoff and landing for rockets. Multiple VTVL craft have flown. As of 2016, VTVL is under intense development as a technology for reusable rockets, with two companies, Blue Origin and SpaceX, both having 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 following a test flight that reached outer space, and SpaceX's Falcon 9 Flight 20 marking the first landing of a commercial orbital booster, both in late 2015.

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.

History

• 1961 Bell Rocket Belt, personal VTVL rocket belt demonstrated.^[1]
• VTVL rocket concepts were studied by Philip Bono of Douglas Aircraft Co. in the 1960s.^[2]
• Apollo Lunar Module was a 1960s two-stage VTVL vehicle for landing and taking off from the moon.
• The Soviet Union did some development work on, but never flew, a vertically-landing manned capsule called Zarya in the late 1980s.^[3]
• The McDonnell Douglas DC-X was an unmanned prototype VTVL launch vehicle that flew several successfully test flights in the 1990s. In June 1996, the vehicle set an altitude record of 3,140 metres (10,300 ft), before making a vertical landing.^[4]
• Between 1998 and 2003 the Japanese Space Agency (JAXA) developed and flew a number of VTVL rocket vehicles in the Reusable Vehicle Testing program
• 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.
• During 2006-2009, Armadillo Aerospace's Scorpius / Super Mod, Masten Space Systems' Xombie and Unreasonable Rocket's Blue Ball flying VTVL rockets competed in the Northrop Grumman / NASA Lunar Lander Challenge. Follow-on VTVL designs including Masten's Xaero and Armadillo's Stig were aimed at higher-speed flight to higher suborbital altitudes.^[5]
• 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.^[6]
• In 2010, three VTVL craft were proffered to NASA in response to NASA's suborbital reusable launch vehicle (sRLV) solicitation under NASA's Flight Operations Program: the Blue Origin New Shepard, the Masten Xaero, and the Armadillo Super Mod.^[7]
• 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.^[8]
• Mighty Eagle is a 2010s Robotic Prototype Lander being developed by NASA^[9]

The Falcon 9's first stage landing on 22 December 2015 after boosting commercial satellites to low earth orbit

• SpaceX announced in September 2011 that they would attempt to develop powered descent and recovery of both Falcon 9 stages, with a VTVL Dragon capsule as well.^[10][11]
  • SpaceX's Grasshopper 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.^[12] The test vehicle made eight successful test^[13] 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.^[14]
  • SpaceX's Falcon 9 Reusable Development Vehicle was approximately 50 feet longer than Grasshopper, and is built on their full-size Falcon 9 v1.1 booster tank, with flight-design landing legs and gaseous nitrogen thrusters to control the booster attitude. F9R Dev1 made its first test flight in April 2014, to an altitude of 250 meters (820 ft) before making a nominal vertical landing.^[15]
• 2013: SpaceX's DragonFly is a prototype low-altitude rocket-powered test article for a propulsively-landed version of their Dragon space capsule. The DragonFly is a suborbital reusable launch vehicle (RLV), intended for low-altitude flight testing expected to start in 2014 and run through at least 2015.^[16]
• On November 23, 2015, Blue Origin's New Shepard booster rocket made the first successful vertical landing following an unmanned suborbital test flight that reached space.^[17]
• On December 21, 2015, SpaceX's 20th Falcon 9 first stage made a successful landing after boosting 11 commercial satellites to low earth orbit on Falcon 9 Flight 20.^[18]
• On April 8, 2016, SpaceX's Falcon 9 made the first successful landing on their Autonomous spaceport drone ship as part of the SpaceX CRS-8 cargo resupply mission to the International Space Station.^[19]

Technology

The technology required to successfully achieve VTVL has several parts. First, thrust must be greater 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 attitude 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. Landing legs and deployment mechanisms add to the weight of the vehicle compared to expendable vehicles, which can reduce performance. Aerodynamics and mass distribution are also crucial; vehicles generally have to be nose heavy during ascent, but need to be stable during landing, usually on their tail, and after touchdown, where they are susceptible to winds.

It can also be necessary to be able to ignite engines in a variety of conditions potentially including vacuum, hypersonic, supersonic, transonic, and subsonic.^[20]

Elon Musk has discussed the potential for substantial reductions in space flight costs as a result of being able to reuse rockets after successful VTVL landings.^[21]

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."^[22] In the 2010s, SpaceX rockets have likewise seen the appellation to this popular culture notion of Buck Rogers in a "Quest to Create a 'Buck Rogers' Reusable Rocket."^[23][24]

See also

• Reusable Vehicle Testing
• Quad (rocket)
• Kankoh-maru – VTVL^[25]
• Project Morpheus NASA program to continue developing ALHAT and Quad landers
• Blue Origin New Shepard
• McDonnell Douglas DC-X
• Zarya
• CORONA
• Grasshopper
• HTHL spacecraft
• VTHL spacecraft
• VTOL aircraft

References

1. American Rocketman Rocket Belt History
2. Wade, Mark. "OOST". Encyclopedia Astronautica. Retrieved 2011-10-04.
3. Zak, Anatoly (2009-04-29). "Russia mulls rocket power 'first'". BBC News. Retrieved 2011-10-11. RKK Energia, ... in the 1980s ... worked on a highly classified project to develop a large manned capsule, called Zarya ("Dawn"), for a wide range of civilian and military missions.
4. Klerkx, Greg: Lost in Space: The Fall of NASA and the Dream of a New Space Age, page 104. Secker & Warburg, 2004
5. X Prize Foundation. "2009 Northrop Grumman Lunar Lander X CHALLENGE". X Prize Foundation. Retrieved October 1, 2012.
6. "Dragon Drop Test – August 20, 2010". Spacex.com. 2010-08-20. Retrieved 2010-12-14.
7. "sRLV platforms compared". NASA. 2011-03-07. 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
8. Bibby, Joe. "Project Morpheus". NASA. Retrieved October 1, 2012.
9. "NASA's 'Mighty Eagle' Robotic Prototype Lander Flies Again at Marshall". NASA. Retrieved August 14, 2012.
10. "Elon Musk says SpaceX will attempt to develop fully reusable space launch vehicle". Washington Post. 2011-09-29. Retrieved 2011-10-11. Both of the rocket’s stages would return to the launch site and touch down vertically, under rocket power, on landing gear after delivering a spacecraft to orbit.
11. Wall, Mike (2011-09-30). "SpaceX Unveils Plan for World's First Fully Reusable Rocket". SPACE.com. Retrieved 2011-10-11.
12. "Reusable rocket prototype almost ready for first liftoff". Spaceflight Now. 2012-07-09. 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.
13. "Grasshopper Completes Highest Leap to Date". SpaceX.com. 10 March 2013. Retrieved 11 March 2013.
14. The Grasshopper prototype test vehicle has been retired. "Grasshopper flies to its highest height to date". Social media information release. SpaceX. 12 October 2013. 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.
15. 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. 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.
16. James, Michael; Salton, Alexandria; Downing, Micah (November 12, 2013). "Draft Environmental Assessment for Issuing an Experimental Permit to SpaceX for Operation of the Dragon Fly Vehicle at the McGregor Test Site, Texas, May 2014 – Appendices" (PDF). Blue Ridge Research and Consulting, LCC. p. 12.
17. "Blue Origin make historic rocket landing." Blue Origin, November 24, 2015. Retrieved: November 24, 2015.
19. https://twitter.com/SpaceX/status/718561436201431040
20. Belfiore, Michael (September 30, 2013). "Musk: SpaceX Now Has "All the Pieces" For Truly Reusable Rockets". Popular Mechanics. Retrieved October 17, 2013.
21. "Reusable rockets cheaper." ZME Science, August 20, 2015. Retrieved: November 24, 2015.
22. "Restoration Center Open House Highlights". New Mexico Museum of Space History. 2013-02-12. 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.
23. "SpaceX Continues its Quest to Create a "Buck Rogers" Reusable Rocket". 21st Century Tech. 2013-03-15. Retrieved 2014-03-24.
24. 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...
25. Anderson, Erik (July 1997). "Kankoh-maru Flight Manual". Space Future. Retrieved 2012-08-04.

External links

• Astronautix.com – List of VTVL rocket concepts from the past
• Hobbyspace.com – Development of VTVL rockets around the world