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. The most successful 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 two 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. 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 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. [40]

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]

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." [42] 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." [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]

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">SpaceX</span> American private spacecraft company

Space Exploration Technologies Corporation, commonly referred to as SpaceX, is an American spacecraft manufacturer, launch service provider, defense contractor and satellite communications company headquartered in Hawthorne, California. The company was founded in 2002 by Elon Musk with the goal of reducing space transportation costs and ultimately developing a sustainable colony on Mars. The company currently operates the Falcon 9 and Falcon Heavy rockets along with the Dragon and Starship spacecraft.

<span class="mw-page-title-main">Launch vehicle</span> Rocket used to carry a spacecraft into space

A launch vehicle is typically a rocket-powered vehicle designed to carry a payload from Earth's surface or lower atmosphere to outer space. The most common form is the ballistic missile-shaped multistage rocket, but the term is more general and also encompasses vehicles like the Space Shuttle. Most launch vehicles operate from a launch pad, supported by a launch control center and systems such as vehicle assembly and fueling. Launch vehicles are engineered with advanced aerodynamics and technologies, which contribute to high operating costs.

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

Falcon 9 is a partially reusable medium-lift launch vehicle that can carry cargo and crew into Earth orbit, designed, manufactured and launched by American aerospace company SpaceX. It can also be used as an expendable heavy-lift launch vehicle. The first Falcon 9 launch was on 4 June 2010. The first Falcon 9 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 and remains the only such vehicle. It is the only U.S. rocket certified for transporting humans to the ISS. In 2022, it became the U.S. rocket with the most launches in history and with the best safety record, having suffered just one flight failure.

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

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

Aircraft can have different ways to take off and land. Conventional airplanes accelerate along the ground until sufficient lift is generated for takeoff, and reverse the process to land. 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 the Falcon 9 and Falcon Heavy.

<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 developed reusable payload fairings for the Falcon 9.

<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.

<span class="mw-page-title-main">Falcon 9 v1.1</span> Second version of SpaceXs Falcon 9 orbital launch vehicle

Falcon 9 v1.1 was the second version of SpaceX's Falcon 9 orbital launch vehicle. The rocket was developed in 2011–2013, made its maiden launch in September 2013, and its final flight in January 2016. The Falcon 9 rocket was fully designed, manufactured, and operated by SpaceX. Following the second Commercial Resupply Services (CRS) launch, the initial version Falcon 9 v1.0 was retired from use and replaced by the v1.1 version.

<span class="mw-page-title-main">Falcon 9 v1.0</span> First member of the Falcon 9 launch vehicle family

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

The Dragon 2 DragonFly was a prototype suborbital rocket-powered test vehicle for a propulsively-landed version of the SpaceX Dragon 2. DragonFly underwent testing in Texas at the McGregor Rocket Test Facility in October 2015. However, the development eventually ceased as the verification burden imposed by NASA was too great to justify it.

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

The Falcon 9 first-stage landing tests were a series of controlled-descent flight tests conducted by SpaceX between 2013 and 2016. Since 2017, the first stage of Falcon 9 missions has been routinely landed if the rocket performance allowed it, and if SpaceX chose to recover the stage.

<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

Falcon 9 flight 20 was a Falcon 9 space launch that occurred on 22 December 2015 at 01:29:00 UTC. It was the first time that the first stage of an orbital rocket made a successful return and vertical landing.

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

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<span class="mw-page-title-main">Landing Zones 1 and 2</span> SpaceXs landing facility at Cape Canaveral Space Force Station

Landing Zone 1 and Landing Zone 2, also known as LZ-1 and LZ-2 respectively, are landing facilities on Cape Canaveral Space Force Station for recovering components of SpaceX's VTVL reusable launch vehicles. LZ-1 and LZ-2 were built on land leased in February 2015, on the site of the former Cape Canaveral Launch Complex 13. SpaceX built Landing Zone 2 at the facility to have a second landing pad, allowing two Falcon Heavy boosters to land simultaneously.

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

Starship is a two-stage super heavy-lift launch vehicle under development by SpaceX. As of April 2024, it is the largest and most powerful rocket ever flown. Starship's primary objective is to lower launch costs significantly via economies of scale. This is achieved by reusing both rocket stages, increasing payload mass to orbit, increasing launch frequency, creating a mass-manufacturing pipeline, and adapting it to a wide range of space missions. Starship is the latest project in SpaceX's decades-long reusable launch system development program and ambition of colonizing Mars.

A floating launch vehicle operations platform is a marine vessel used for launch or landing operations of an orbital launch vehicle by a launch service provider: putting satellites into orbit around Earth or another celestial body, or recovering first-stage boosters from orbital-class flights by making a propulsive landing on the platform.

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