Launch escape system

Last updated
Apollo LES pad abort test with boilerplate Command Module. Apollo Pad Abort Test -2.jpg
Apollo LES pad abort test with boilerplate Command Module.

A launch escape system (LES) or launch abort system (LAS) is a crew-safety system connected to a space capsule. It is used in the event of a critical emergency to quickly separate the capsule from its launch vehicle in case of an emergency requiring the abort of the launch, such as an impending explosion. The LES is typically controlled by a combination of automatic rocket failure detection, and a manual activation for the crew commander's use. The LES may be used while the launch vehicle is on the launch pad, or during its ascent. Such systems are usually of three types:

Contents

History

The escape system unintentionally blasted off from the Mercury spacecraft on the failed Mercury-Redstone 1 mission Escape rocket of Mercury-Redstone 1.jpg
The escape system unintentionally blasted off from the Mercury spacecraft on the failed Mercury-Redstone 1 mission
The escape tower used by Shenzhou Escape tower - NMC.jpg
The escape tower used by Shenzhou

The idea of using a rocket to remove the capsule from a space vehicle was developed by Maxime Faget in 1958. [1] The system, using the tower on the top of the space capsule to house rockets, was first used on a test of the Project Mercury capsule in March 1959. Historically, LES were used on American Mercury and Apollo spacecraft. Both designs used a solid-fuel rocket motor. The Mercury LES was built by the Grand Central Rocket Company in Redlands, California (which later became the Lockheed Propulsion Company). Apollo used a design that had many similarities to the Mercury system. LES continue to be used on the Russian Soyuz and Chinese Shenzhou spacecraft. The SpaceX designed Dragon 2 uses a hypergolic liquid-fueled launch abort system integrated to the capsule and the Boeing Starliner uses abort thrusters in its service module.

Subsystems of Launch Escape System (Indian Space Research Organization, 2023) TVD1-Brochure elements 22.png
Subsystems of Launch Escape System (Indian Space Research Organization, 2023)

The Soviet Vostok and American Gemini spacecraft both made use of ejection seats. The European Space Agency's Hermes and the Soviet Buran-class spaceplanes would also have made use of them if they had ever flown with crews. As shown by Soyuz T-10a, a LES must be able to carry a crew compartment from the launch pad to a height sufficient for its parachutes to open. Consequently, they must make use of large, powerful (and heavy) solid rockets. The Soyuz launch escape system is called CAC or SAS, from the Russian/transliterated Russian Система Аварийного Спасения or Sistema Avariynogo Spaseniya, meaning emergency rescue system. [2]

The Soviet Proton launcher has flown dozens of times with an escape tower, under the Zond program and the TKS program.[ citation needed ] All of its flights were uncrewed.

The Space Shuttle was fitted with ejection seats for the two pilots in the initial test flights, but these were removed once the vehicle was deemed operational and carried additional crew members, [3] which could not be provided with escape hatches. Following the 1986 Challenger disaster, all surviving orbiters were fitted to allow for crew evacuation through the main ingress/egress hatch (using a specially developed parachute system that could be worn over a spacesuit), [3] although only when the Shuttle was in a controlled glide.

A Dragon 2 undergoing a Pad Abort test on May 6, 2015, demonstrating a "pusher" LAS. Crew Dragon Pad Abort Test (16814592054).jpg
A Dragon 2 undergoing a Pad Abort test on May 6, 2015, demonstrating a "pusher" LAS.

The Orion spacecraft which was developed to follow the Space Shuttle program uses a Mercury and Apollo-style escape rocket system, while an alternative system, called the Max Launch Abort System (MLAS), [4] was investigated and would have used existing solid-rocket motors integrated into the bullet-shaped protective launch shroud.

Under NASA's Commercial Crew Development (CCDev) program Blue Origin was awarded $3.7 million for development of an innovative 'pusher' LAS, it is used on the New Shepard Crew Capsule. [5]

Also under NASA's CCDev program, SpaceX was awarded $75 million for the development of their own version of a "pusher" LAS. [6] Their Dragon 2 spacecraft uses its SuperDraco engines during a launch abort scenario. Although often referred to as a "pusher" arrangement since it lacks a tower, the Dragon 2 LAS removes both the capsule and its trunk together from the launch vehicle. The system is designed to abort with the SuperDraco engines at the top of the abort stack as occurs with a more traditional tractor LAS. The concept was first tested in a Pad Abort test conducted at SLC-40, Cape Canaveral Air Force Station, on May 6, 2015. [7] SpaceX tested the system on January 19, 2020 during a full-scale simulation of a Falcon 9 rocket malfunction at Kennedy Space Center Launch Complex 39, from where it has later launched crews to the International Space Station. [8]

The second crewed spacecraft selected by NASA for its CCDEV program was Boeing's CST-100 Starliner, which, like SpaceX's Dragon 2 spacecraft, uses a "pusher" launch escape system, consisting of four launch abort engines mounted on the service module that can propel the spacecraft away from its Atlas V launch vehicle in the event of an emergency on the pad or during ascent. [9] The engines, which use hypergolic propellants and generate 40,000 pounds-force of thrust each, are provided by Aerojet Rocketdyne. [10] The abort system was tested successfully during the Starliner's pad abort test on November 4, 2019 at White Sands Missile Range. [11]

Orbital Sciences Corporation intends[ when? ] to sell the LAS it was building for the Orion spacecraft to future commercial crew vehicle providers in the wake of the cancellation of the Constellation project. [12]

Usage

ISRO Gaganyaan boilerplate during its launch escape system pad abort test, 5 July 2018. ISRO Pad abort test Crew Module lifting off.jpg
ISRO Gaganyaan boilerplate during its launch escape system pad abort test, 5 July 2018.

During the Mercury-Redstone 1 mission on November 21, 1960, the escape system unintentionally blasted off from the Mercury spacecraft after the Redstone booster engine shut down just after ignition on the pad. The spacecraft remained attached to the booster on the ground.

An accidental pad firing of a launch escape system occurred during the attempted launch of the uncrewed Soyuz 7K-OK No.1 spacecraft on December 14, 1966. The vehicle's strap-on boosters did not ignite, preventing the rocket from leaving the pad. About 30 minutes later, while the vehicle was being secured, the LES engine fired. Separation charges started a fire in the rocket's third stage, leading to an explosion that killed a pad worker. During the attempted launch, the booster switched from external to internal power as it normally would do, which then activated the abort sensing system. Originally it was thought that the LES firing was triggered by a gantry arm that tilted the rocket past 7 degrees, meeting one of the defined in-flight abort conditions. [13]

Soviet officers watch as the Soyuz T-10 capsule aborts from the launch pad (September 1983). Soyuz T-10-1 abort.jpg
Soviet officers watch as the Soyuz T-10 capsule aborts from the launch pad (September 1983).

The first usage with a crewed mission occurred during the attempt to launch Soyuz T-10-1 on September 26, 1983.[ citation needed ] The rocket caught fire, just before launch, and the LES carried the crew capsule clear, seconds before the rocket exploded. The crew were subjected to an acceleration of 14 to 17 g (140 to 170 m/s2) for five seconds and were badly bruised. Reportedly, the capsule reached an altitude of 2,000 meters (6,600 ft) and landed 4 kilometers (2.5 mi) from the launch pad.

On October 11, 2018 the crew of Soyuz MS-10 separated from their launch vehicle after a booster rocket separation failure occurred at an altitude of 50 km during the ascent. However, at this point in the mission the LES had already been ejected and was not used to separate the crew capsule from the rest of the launch vehicle. Backup motors were used to separate the crew capsule resulting in the crew landing safely and uninjured approximately 19 minutes after launch.

On September 12, 2022 during Blue Origin New Shepard flight NS-23, the booster's BE-3 engine suffered a failure at about 1 minute into the flight. The launch escape system was triggered and the capsule successfully separated and landed nominally. The flight was carrying microgravity scientific payloads in the crew capsule, without crew on board. [14]

See also

Related Research Articles

<span class="mw-page-title-main">Human spaceflight</span> Spaceflight with a crew or passengers

Human spaceflight is spaceflight with a crew or passengers aboard a spacecraft, often with the spacecraft being operated directly by the onboard human crew. Spacecraft can also be remotely operated from ground stations on Earth, or autonomously, without any direct human involvement. People trained for spaceflight are called astronauts, cosmonauts (Russian), or taikonauts (Chinese); and non-professionals are referred to as spaceflight participants or spacefarers.

<span class="mw-page-title-main">Soyuz (spacecraft)</span> Series of spacecraft designed for the Soviet space programme

Soyuz is a series of spacecraft which has been in service since the 1960s, having made more than 140 flights. It was designed for the Soviet space program by the Korolev Design Bureau. The Soyuz succeeded the Voskhod spacecraft and was originally built as part of the Soviet crewed lunar programs. It is launched on a Soyuz rocket from the Baikonur Cosmodrome in Kazakhstan. Between the 2011 retirement of the Space Shuttle and the 2020 demo flight of SpaceX Crew Dragon, the Soyuz served as the only means to ferry crew to or from the International Space Station, for which it remains heavily used. Although China did launch crewed Shenzhou flights during this time, none of them docked with the ISS.

Human spaceflight programs have been conducted, started, or planned by multiple countries and companies. Until the 21st century, human spaceflight programs were sponsored exclusively by governments, through either the military or civilian space agencies. With the launch of the privately funded SpaceShipOne in 2004, a new category of human spaceflight programs – commercial human spaceflight – arrived. By the end of 2022, three countries and one private company (SpaceX) had successfully launched humans to Earth orbit, and two private companies had launched humans on a suborbital trajectory.

<span class="mw-page-title-main">Mercury-Redstone 1</span> Test flight of the Redstone rocket and Mercury spacecraft

Mercury-Redstone 1 (MR-1) was the first Mercury-Redstone uncrewed flight test in Project Mercury and the first attempt to launch a Mercury spacecraft with the Mercury-Redstone Launch Vehicle. Intended to be an uncrewed sub-orbital spaceflight, it was launched on November 21, 1960 from Cape Canaveral Air Force Station, Florida. The launch failed in an abnormal fashion: immediately after the Mercury-Redstone rocket started to move, it shut itself down and settled back on the pad, after which the capsule jettisoned its escape rocket and deployed its recovery parachutes. The failure has been referred to as the "four-inch flight", for the approximate distance traveled by the launch vehicle.

<span class="mw-page-title-main">Little Joe II</span> American rocket

Little Joe II was an American rocket used from 1963 to 1966 for five uncrewed tests of the Apollo spacecraft launch escape system (LES), and to verify the performance of the command module parachute recovery system in abort mode. It was named after a similar rocket designed for the same function in Project Mercury. Launched from White Sands Missile Range in New Mexico, it was the smallest of four launch rockets used in the Apollo program.

<span class="mw-page-title-main">Space capsule</span> Type of spacecraft

A space capsule is a spacecraft designed to transport cargo, scientific experiments, and/or astronauts to and from space. Capsules are distinguished from other spacecraft by the ability to survive reentry and return a payload to the Earth's surface from orbit or sub-orbit, and are distinguished from other types of recoverable spacecraft by their blunt shape, not having wings and often containing little fuel other than what is necessary for a safe return. Capsule-based crewed spacecraft such as Soyuz or Orion are often supported by a service or adapter module, and sometimes augmented with an extra module for extended space operations. Capsules make up the majority of crewed spacecraft designs, although one crewed spaceplane, the Space Shuttle, has flown in orbit.

Apollo abort modes were procedures by which the nominal launch of an Apollo spacecraft, either the Saturn IB or Saturn V rocket, could be terminated. The abort of the flight allowed for the rescue of the crew if the rocket failed catastrophically. Depending on how far the flight had progressed, different procedure or modes would be used. In the history of the Apollo Program, none of the abort modes were ever used on any of the fifteen crewed Apollo spacecraft flights.

<span class="mw-page-title-main">Boilerplate (spaceflight)</span> Nonfunctional spacecraft or payload

A boilerplate spacecraft, also known as a mass simulator, is a nonfunctional craft or payload that is used to test various configurations and basic size, load, and handling characteristics of rocket launch vehicles. It is far less expensive to build multiple, full-scale, non-functional boilerplate spacecraft than it is to develop the full system. In this way, boilerplate spacecraft allow components and aspects of cutting-edge aerospace projects to be tested while detailed contracts for the final project are being negotiated. These tests may be used to develop procedures for mating a spacecraft to its launch vehicle, emergency access and egress, maintenance support activities, and various transportation processes.

<span class="mw-page-title-main">Orion abort modes</span> Launch abort modes used by the Orion spacecraft

The Orion Multi-Purpose Crew Vehicle is equipped with a launch escape system. Orion has several abort modes. Some of these may not use the LAS itself, but would use the second stage of the SLS, or even the Orion vehicle's own propulsion system instead.

A pad abort test is a kind of test of a launch escape system which conducted by setting the system along with the spacecraft still on the ground and let the system activate to carry the spacecraft flying away, then separate in the air and make the spacecraft land safely. The purpose of the test is to determine how well the system could get the crew of a spacecraft to safety in an emergency on the launch pad. As the spacecraft is set still on the ground, the test is also called "zero-altitude abort test" in against "high-altitude abort test".

<span class="mw-page-title-main">SpaceX Draco</span> Line of hypergolic liquid rocket engines by SpaceX

The SpaceX Draco is a hypergolic liquid rocket engine designed and built by SpaceX for use in their space capsules. Two engine types have been built to date: Draco and SuperDraco.

<span class="mw-page-title-main">Boeing Starliner</span> Class of partially reusable crew capsules

The Boeing Starliner is a class of partially reusable spacecraft designed to transport crew to the International Space Station (ISS) and other low-Earth-orbit destinations. It is manufactured by Boeing, with the Commercial Crew Program (CCP) of NASA as the anchor customer. The spacecraft consists of a reusable crew capsule and an expendable service module.

<span class="mw-page-title-main">Development of the Commercial Crew Program</span> NASA space program partnership with space companies

Development of the Commercial Crew Program began in the second round of the Commercial Crew Development (CCDev) program, which was rescoped from a technology development program for human spaceflight to a competitive development program that would produce the spacecraft to be used in the Commercial Crew Program to provide crew transportation services to and from the International Space Station (ISS). To implement the program NASA awarded a series of competitive fixed-price contracts to private vendors starting in 2011. Operational contracts to fly astronauts were awarded in September 2014 to SpaceX and Boeing, and NASA expected each company to complete development and achieve crew rating in 2017. Each company performed an uncrewed orbital test flight in 2019. SpaceX operational flights started in November 2020.

<span class="mw-page-title-main">SpaceX Dragon 2</span> 2020s class of partially reusable spacecraft

Dragon 2 is a class of partially reusable spacecraft developed, manufactured, and operated by American space company SpaceX, primarily for flights to the International Space Station (ISS). SpaceX also launches private missions, such as Inspiration4 and Axiom Space Missions. There are two variants of the Dragon spacecraft: Crew Dragon, a spacecraft capable of ferrying four crewmembers, and Cargo Dragon, a replacement for the original Dragon 1 used to carry freight to and from space. The spacecraft consists of a reusable space capsule and an expendable trunk module. The spacecraft launches atop a Falcon 9 Block 5 rocket and the capsule returns to Earth through splashdown. It has proven to be the most cost effective spacecraft in history to be used by NASA.

<span class="mw-page-title-main">Boeing Crewed Flight Test</span> Planned first crewed flight of Boeing Starliner

Boeing Crew Flight Test (Boe-CFT) will be the first crewed mission of the Boeing Starliner and the third orbital flight test of the Starliner overall after the two uncrewed orbital flight tests, Boe-OFT and Boe-OFT 2 in 2019 and 2022. The flight was scheduled for liftoff at 2:34 on 7 May UTC, but was scrubbed about two hours before liftoff. The cause of the scrub was due to an oxygen valve problem on the United Launch Alliance's (ULA) Atlas V, and not due to any anomaly on the Starliner portion of the rocket. The launch is now scheduled to occur no earlier than 21 May at 20:43 UTC.

<span class="mw-page-title-main">Soyuz abort modes</span> Soyuz spacecraft emergency crew rescue systems

In the event of catastrophic failure, the Soyuz spacecraft has a series of automated and semi-automated abort modes to rescue the crew. The abort systems have been refined since the first piloted flights and all abort scenarios for the Soyuz MS are expected to be survivable for the crew.

Zond program was a Soviet robotic spacecraft program launched between 1964 and 1970, using two spacecraft series, one for interplanetary exploration, and the other for lunar exploration.

<span class="mw-page-title-main">Crew Dragon In-Flight Abort Test</span> Post-launch abort test of the SpaceX Dragon 2 spacecraft

SpaceXCrew Dragon In-Flight Abort Test was a successful test of the SpaceX Dragon 2 abort system, conducted on 19 January 2020. It was the final assessment for the Crew Dragon capsule and Falcon 9 launch system before they would be certified to carry humans into space. Booster B1046.4 and an uncrewed capsule C205 were launched from Launch Complex 39A (LC-39A) on a suborbital trajectory, followed by an in-flight abort of the capsule at max Q and supersonic speed. The test was carried out successfully: the capsule pulled itself away from the booster after launch control commanded the abort, and landed safely.

<span class="mw-page-title-main">Commercial Crew Program</span> NASA human spaceflight program for the International Space Station

The Commercial Crew Program (CCP) provides commercially operated crew transportation service to and from the International Space Station (ISS) under contract to NASA, conducting crew rotations between the expeditions of the International Space Station program. American space manufacturer SpaceX began providing service in 2020, using the Crew Dragon spacecraft, and NASA plans to add Boeing when its Boeing Starliner spacecraft becomes operational no earlier than 2025. NASA has contracted for six operational missions from Boeing and fourteen from SpaceX, ensuring sufficient support for ISS through 2030.

<span class="mw-page-title-main">Crew Dragon C205</span> Space capsule

Crew Dragon C205 is a Crew Dragon capsule manufactured and built by SpaceX. It completed its only flight on January 19, 2020, with the Crew Dragon In-Flight Abort Test mission where the capsule detached from the Falcon 9 B1046 booster at max q using the SuperDraco abort thrusters. This was done to test the functionality of the abort thrusters in an operational rocket launch.

References

PD-icon.svg This article incorporates public domain material from websites or documents of the National Aeronautics and Space Administration .

  1. ↑ "astronautix Escape Tower". Archived from the original on 2013-11-08.
  2. ↑ McHale, Suzy. "Soyuz launch escape system – RuSpace". suzymchale.com. Archived from the original on 21 February 2014. Retrieved 23 April 2018.
  3. 1 2 Betancourt, Mark. "They Said It Wasn't Possible to Escape the Space Shuttle. These Guys Showed It Was". Smithsonian Magazine. Retrieved 2022-08-22.
  4. ↑ NASA Spaceflight: Orion MLAS Archived 2007-12-08 at the Wayback Machine .
  5. ↑ Foust, Jeff. "Blue Origin proposes orbital vehicle". Archived from the original on 2021-01-18. Retrieved 2010-02-19.
  6. ↑ Morring Jr., Frank. "NASA Provides Seed Money For CCDev-2". Archived from the original on 2011-05-10. Retrieved 2022-04-25.
  7. ↑ Post, Hannah (6 May 2015). "Crew Dragon Completes Pad Abort Test". spacex.com. Archived from the original on 9 January 2016. Retrieved 23 April 2018.
  8. ↑ "SpaceX moves launch of Dragon abort test to KSC". Local 6. Archived from the original on 2015-07-04. Retrieved 2015-07-04.
  9. ↑ "Boeing's Starliner launch abort engine suffers problem during testing". 22 July 2018. Archived from the original on 25 April 2022. Retrieved 22 April 2019.
  10. ↑ "Boeing's Starliner launch abort engine suffers problem during testing". 22 July 2018. Archived from the original on 25 April 2022. Retrieved 22 April 2019.
  11. ↑ Clark, Stephen. "Boeing tests crew capsule escape system – Spaceflight Now". Archived from the original on 2019-12-14. Retrieved 2020-06-24.
  12. ↑ Clark, Stephen. "Orbital sees bright future for Orion launch abort system". Archived from the original on 2010-02-22. Retrieved 2010-02-19.
  13. ↑ "Kamanin Diaries". Encyclopedia Astronautica. Archived from the original on 17 August 2013. Retrieved 18 May 2016.
  14. ↑ Davenport, Justin (12 September 2022). "New Shepard suffers in-flight abort on uncrewed NS-23 mission". NASASpaceflight.com. Retrieved 12 September 2022.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.