VTVL

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Apollo 16 LM Orion on the lunar surface, 1972 Apollo16LM.jpg
Apollo 16 LM Orion on the lunar surface, 1972
DC-XA landing in 1996 DC-XA first landing.jpg
DC-XA landing in 1996
A Falcon 9 first stage performing a vertical landing, 2016 Falcon 9 first stage landing on Droneship.jpg
A Falcon 9 first stage performing a vertical landing, 2016

Vertical takeoff, vertical landing (VTVL) is a form of takeoff and landing for rockets. Multiple VTVL craft have flown. A notable VTVL vehicle was the Apollo Lunar Module which delivered the first humans to the Moon. Building on the decades of development, SpaceX utilised the VTVL concept for its flagship Falcon 9 first stage, which has delivered over three hundred successful powered landings so far.

Contents

VTVL technologies were first seriously developed for the Apollo program. By the '90s, development on large reliable restartable rocket engines made it possible to use the already matured technology for rocket stages. The first pioneer was the McDonnell Douglas DC-X demonstrator. After the success of the DC-X prototype, the concept was developed substantially with small rockets after 2000, in part due to incentive prize competitions like the Lunar Lander Challenge.

Starting in the mid-2000s, VTVL was under intense development as a technology for reusable rockets large enough to transport people. From 2005 to 2007 Blue Origin did a series of successful tests, first with the jet powered Charon demonstrator, later using the Goddard demonstrator. Small VTVL rockets were also developed by Masten Space Systems, Armadillo Aerospace, and others. In 2013, after the failure of stage recovery with parachutes, 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. Many launches 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] Starship became the first launch vehicle to demonstrate the technology with both of its stages on its fourth test flight.

VTVL rockets are not to be confused with aircraft that take off and land vertically and use air for support and propulsion, such as helicopters and jump jets which are VTOL aircraft.

History

A Falcon 9 first stage landing on 21 December 2015 after boosting commercial satellites to low Earth orbit ORBCOMM-2 (23282658734).jpg
A Falcon 9 first stage landing on 21 December 2015 after boosting commercial satellites to low Earth orbit

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, the thrust is normally required to be vectored and requires some degree of throttling. However, a thrust-to-weight ratio of more than 1 is not strictly necessary.

The vehicle must be capable of calculating its position and altitude; small deviations from the vertical can cause large deviations in the vehicle’s horizontal position. RCS systems are usually required to keep the vehicle at the correct angle. SpaceX also uses grid fins for attitude control during the landing of their Falcon 9 boosters.

It can also be necessary to be able to ignite engines in a variety of conditions potentially including vacuum, hypersonic, supersonic, transonic, and subsonic. [44]

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. [45]

Vertical landing rocket depicted in 1951 comic Rocket Ship X Rocket Ship X comic book.jpg
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." [46] 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." [47] [48]

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. [49] [50] [51] [52]

See also

Related Research Articles

<span class="mw-page-title-main">Reusable launch vehicle</span> Vehicles that can go to space and return

A reusable launch vehicle has parts that can be recovered and reflown, while carrying payloads from the surface to outer space. Rocket stages are the most common launch vehicle parts aimed for reuse. Smaller parts such as rocket engines and boosters can also be reused, though reusable spacecraft may be launched on top of an expendable launch vehicle. Reusable launch vehicles do not need to make these parts for each launch, therefore reducing its launch cost significantly. However, these benefits are diminished by the cost of recovery and refurbishment.

<span class="mw-page-title-main">Lockheed Martin X-33</span> Uncrewed re-usable spaceplane technology demonstrator for the VentureStar

The Lockheed Martin X-33 was a proposed uncrewed, sub-scale technology demonstrator suborbital spaceplane that was developed for a period in the 1990s. The X-33 was a technology demonstrator for the VentureStar orbital spaceplane, which was planned to be a next-generation, commercially operated reusable launch vehicle. The X-33 would flight-test a range of technologies that NASA believed it needed for single-stage-to-orbit reusable launch vehicles, such as metallic thermal protection systems, composite cryogenic fuel tanks for liquid hydrogen, the aerospike engine, autonomous (uncrewed) flight control, rapid flight turn-around times through streamlined operations, and its lifting body aerodynamics.

<span class="mw-page-title-main">Falcon 9</span> Orbital launch vehicle by SpaceX

Falcon 9 is a partially reusable, human-rated, two-stage-to-orbit, medium-lift launch vehicle designed and manufactured in the United States by SpaceX. The first Falcon 9 launch was on 4 June 2010, and the first commercial resupply mission to the International Space Station (ISS) launched on 8 October 2012. In 2020, it became the first commercial rocket to launch humans to orbit. The Falcon 9 has an exceptional safety record, with 394 successful launches, two in-flight failures, one partial failure and one pre-flight destruction. It is the most-launched American orbital rocket in history.

<span class="mw-page-title-main">Falcon Heavy</span> SpaceX heavy-lift launch vehicle

Falcon Heavy is a super heavy-lift launch vehicle with partial reusability that can carry cargo into Earth orbit, and beyond. It is designed, manufactured and launched by American aerospace company SpaceX.

Aircraft have different ways to take off and land. Conventional airplanes accelerate along the ground until reaching a speed that is sufficient for the airplane to takeoff and climb at a safe speed. Some airplanes can take off at low speed, this being a short takeoff. Some aircraft such as helicopters and Harrier jump jets can take off and land vertically. Rockets also usually take off vertically, but some designs can land horizontally.

<span class="mw-page-title-main">Falcon 9 prototypes</span> Test vehicles developed by SpaceX

Falcon 9 prototypes were experimental flight test reusable rockets that performed vertical takeoffs and landings. The project was privately funded by SpaceX, with no funds provided by any government until later on. Two prototypes were built, and both were launched from the ground.

<span class="mw-page-title-main">SpaceX launch vehicles</span> Launch vehicles developed and operated by SpaceX

SpaceX manufactures launch vehicles to operate its launch provider services and to execute its various exploration goals. SpaceX currently manufactures and operates the Falcon 9 Block 5 family of medium-lift launch vehicles and the Falcon Heavy family of heavy-lift launch vehicles – both of which are powered by SpaceX Merlin engines and employ VTVL technologies to reuse the first stage. As of 2024, the company is also developing the fully reusable Starship launch system, which will replace Falcon 9, Falcon Heavy, and Dragon.

<span class="mw-page-title-main">SpaceX reusable launch system development program</span> Effort by SpaceX to make rockets that can fly multiple times

SpaceX has privately funded the development of orbital launch systems that can be reused many times, similar to the reusability of aircraft. SpaceX has developed technologies over the last decade to facilitate full and rapid reuse of space launch vehicles. The project's long-term objectives include returning a launch vehicle first stage to the launch site within minutes and to return a second stage to the launch pad, following orbital realignment with the launch site and atmospheric reentry in up to 24 hours. SpaceX's long term goal would have been reusability of both stages of their orbital launch vehicle, and the first stage would be designed to allow reuse a few hours after return. Development of reusable second stages for Falcon 9 was later abandoned in favor of developing Starship. However, SpaceX still developed reusable payload fairings for the Falcon 9.

<span class="mw-page-title-main">SpaceX CRS-8</span> 2016 American spaceflight to the ISS

SpaceX CRS-8, also known as SpX-8, was a Commercial Resupply Service mission to the International Space Station (ISS) which was launched on April 8, 2016, at 20:43 UTC. It was the 23rd flight of a Falcon 9 rocket, the tenth flight of a Dragon cargo spacecraft and the eighth operational mission contracted to SpaceX by NASA under the Commercial Resupply Services program. The capsule carried over 3,100 kilograms (6,800 lb) of cargo to the ISS including the Bigelow Expandable Activity Module (BEAM), a prototype inflatable space habitat delivered in the vehicle's trunk, which was attached to the station and, as of May 2022, is expected to remain so for five more full years of in-orbit viability tests.

<span class="mw-page-title-main">SpaceX facilities</span> Launch facilities used by SpaceX

As of 2023, SpaceX operates four launch facilities: Cape Canaveral Space Launch Complex 40 (SLC-40), Vandenberg Space Force Base Space Launch Complex 4E (SLC-4E), Kennedy Space Center Launch Complex 39A (LC-39A), and Brownsville South Texas Launch Site (Starbase). Space Launch Complex 40 was damaged in the AMOS-6 accident in September 2016 and repair work was completed by December 2017. SpaceX believes that they can optimize their launch operations, and reduce launch costs, by dividing their launch missions amongst these four launch facilities: LC-39A for NASA launches, SLC-40 for United States Space Force national security launches, SLC-4E for polar launches, and South Texas Launch Site for commercial launches.

The DARPA XS-1 was an experimental spaceplane/booster with the planned capability to deliver small satellites into orbit for the U.S. Military. It was reported to be designed to be reusable as frequently as once a day, with a stated goal of doing so for 10 days straight. The XS-1 was intended to directly replace the first stage of a multistage rocket by taking off vertically and flying to hypersonic speed and high suborbital altitude, enabling one or more expendable upper stages to separate and deploy a payload into low Earth orbit. The XS-1 would then return to Earth, where it could ostensibly be serviced fast enough to repeat the process at least once every 24 hours.

<span class="mw-page-title-main">Falcon 9 v1.1</span> Second version of the SpaceX medium-lift launch vehicle

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<span class="mw-page-title-main">Falcon 9 v1.0</span> First version of the SpaceX medium-lift launch vehicle

The Falcon 9 v1.0 was the first member of the Falcon 9 launch vehicle family, designed and manufactured by SpaceX in Hawthorne, California. Development of the medium-lift launcher began in 2005, and it first flew on June 4, 2010. The Falcon 9 v1.0 then launched four Dragon cargo spacecraft: one on an orbital test flight, then one demonstration and two operational resupply missions to the International Space Station under a Commercial Resupply Services contract with NASA.

Dragon 2 <i>DragonFly</i> SpaceX Dragon 2 spacecraft prototype

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<span class="mw-page-title-main">Falcon 9 first-stage landing tests</span> Proofs of the SpaceX boosters reusability

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<span class="mw-page-title-main">Falcon 9 flight 20</span> Falcon 9 space launch that occurred on 22 December 2015 at 01:29:00 UTC

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<span class="mw-page-title-main">Falcon 9 Full Thrust</span> Third version of the SpaceX medium-lift launch vehicle

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LinkSpace or Link Space Aerospace Technology Inc. is a Chinese private space launch company based in Beijing. It is led by CEO Hu Zhenyu, and founded as the first private rocket firm in China. The company was founded in 2014, by Hu Zhenyu, a graduate of South China University of Technology; Yan Chengyi, a graduate of Tsinghua University; and Wu Xiaofei, a manufacturing expert. The company is registered in Shenzhen.

<span class="mw-page-title-main">SpaceX Starship</span> Reusable super heavy-lift launch vehicle

Starship is a two-stage fully reusable super heavy-lift launch vehicle under development by American aerospace company SpaceX. On April 20, 2023, with the first Integrated Flight Test, Starship became the most massive and most powerful vehicle ever to fly. It was cleared to begin satellite deployments following the sixth test flight. SpaceX has developed Starship with the intention of lowering launch costs using economies of scale, aiming to achieve this by reusing both rocket stages by "catching" them with the launch tower's systems, increasing payload mass to orbit, increasing launch frequency, mass-manufacturing the rockets and adapting it to a wide range of space missions. Starship is the latest project in SpaceX's reusable launch system development program and plan to colonize Mars.

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