Electromagnetic catapult

Last updated

An illustration of the EMALS EMALS-768x428.png
An illustration of the EMALS

An electromagnetic catapult, also called EMALS ("electromagnetic aircraft launch system") after the specific US system, is a type of aircraft launching system. Currently, only the United States and China have successfully developed it, and it is installed on the Gerald R. Ford-class aircraft carriers and the Chinese aircraft carrier Fujian. The system launches carrier-based aircraft by means of a catapult employing a linear induction motor rather than the conventional steam piston.

Contents

Electromagnetic catapults have several advantages over their steam-based counterparts. Because the rate of aircraft acceleration is more uniform (and is configurable), stress on the airframe is reduced considerably, resulting in increased safety and endurance and lower maintenance costs for the aircraft. Electromagnetic systems also weigh less, are expected to cost less and require less maintenance, and can launch both heavier and lighter aircraft than steam catapults. They also take up less space below the flight deck and require no fresh water for their operation, thus reducing the need for energy-intensive desalination.

History

Developed in the 1950s, steam catapults have proven exceptionally reliable. Carriers equipped with four steam catapults have been able to use at least one of them at 99.5% of the time. [1] However, several drawbacks. One group of Navy engineers wrote: "The foremost deficiency is that the catapult operates without feedback control. With no feedback, there often occurs large transients in tow forces that can damage or reduce the life of the airframe." [2] The steam system is massive, inefficient (4–6%), [3] and hard to control. These control problems allow Nimitz-class aircraft carrier steam-powered catapults to launch heavy aircraft, but not aircraft as light as many unmanned aerial vehicles.

General Atomics Electromagnetic Systems (GA-EMS) developed the first operational modern electromagnetic catapult, [4] named Electromagnetic Aircraft Launch System (EMALS), for the United States Navy. The system was installed on USS Gerald R. Ford aircraft carrier, replacing traditional steam catapults. This innovation eliminates the traditional requirement to generate and store steam, freeing up considerable area below deck. With the EMALS, Gerald R. Ford can accomplish 25% more aircraft launches per day than the Nimitz class and requires 25% fewer crew members. [5] The EMALS uses a linear induction motor (LIM), which uses alternating current (AC) to generate magnetic fields that propel a carriage along a track to launch the aircraft. [6] [7] A system somewhat similar to EMALS, Westinghouse's electropult, was developed in 1946 but not deployed. [8]

China developed an electromagnetic catapult system in the 2000s for aircraft carriers, but with a different technical approach. Chinese adopted a medium-voltage, direct current (DC) power transmission system, [9] instead of the alternating current catapult system that United States developed. [6] [10]

Systems under development

The concept of a ground carriage is intended for civilian use and takes the idea of an electromagnetic aircraft launch system one step further, with the entire landing gear remaining on the runway for both takeoff and landing. [11]

China

Rear Admiral Yin Zhuo of the Chinese Navy has said that China's next aircraft carrier will also have an electromagnetic aircraft launch system. [12] Multiple prototypes have been spotted by the media in 2012, and aircraft capable of electromagnetic launching are undergoing testing at a Chinese Navy research facility. [13]

According to a report in July 2017, the construction of the Type 003 aircraft carrier has been rescheduled in order to choose between a steam or electromagnetic catapult and the latest competition results shows that the electromagnetic launchers will be used in the Type 003 aircraft carrier. [14] [15]

China's military chief claims a breakthrough in electromagnetic launch systems for aircraft carriers has been made, and will utilize such a system in the third aircraft carrier that China will build after Type 002. The launch system is powered by fossil fuel via generators and capacitors. [16] [17] [18] The design on the Type 003 carrier is being led by Rear Admiral Ma Weiming.

China's electromagnetic catapult has been installed on its third aircraft carrier, the aircraft carrier Fujian. [19] [20]

Russia

Russia's United Shipbuilding Corporation (USC) is developing new launch systems for warplanes based on aircraft carriers, USC President Alexei Rakhmanov told TASS on 4 July 2018. [21]

United States

General Atomics EMALS was designed for and into the Gerald R. Ford-class aircraft carrier. [22] A proposal to retrofit it into Nimitz-class carriers was rejected. John Schank said: "The biggest problems facing the Nimitz class are the limited electrical power generation capability and the upgrade-driven increase in ship weight and erosion of the center-of-gravity margin needed to maintain ship stability." [23]

Ships with electromagnetic catapult

United States

Gerald R. Ford-class aircraft carrier (in service)

China

Chinese aircraft carrier Fujian (outfitting)

Type 076 landing helicopter dock (planned) [24]

Type 004 aircraft carrier (planned)

France

Future French aircraft carrier (planned)

Russia

Project 23000E (proposed)

See also

Related Research Articles

<span class="mw-page-title-main">Aircraft carrier</span> Warship that serves as a seagoing airbase

An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and facilities for carrying, arming, deploying, and recovering aircraft. Typically, it is the capital ship of a fleet, as it allows a naval force to project air power worldwide without depending on local bases for staging aircraft operations. Carriers have evolved since their inception in the early twentieth century from wooden vessels used to deploy balloons to nuclear-powered warships that carry numerous fighters, strike aircraft, helicopters, and other types of aircraft. While heavier aircraft such as fixed-wing gunships and bombers have been launched from aircraft carriers, these aircraft have not landed on a carrier. By its diplomatic and tactical power, its mobility, its autonomy and the variety of its means, the aircraft carrier is often the centerpiece of modern combat fleets. Tactically or even strategically, it replaced the battleship in the role of flagship of a fleet. One of its great advantages is that, by sailing in international waters, it does not interfere with any territorial sovereignty and thus obviates the need for overflight authorizations from third-party countries, reduces the times and transit distances of aircraft and therefore significantly increases the time of availability on the combat zone.

<i>Nimitz</i>-class aircraft carrier US Navy nuclear-powered aircraft carrier class

The Nimitz class is a class of ten nuclear-powered aircraft carriers in service with the United States Navy. The lead ship of the class is named after World War II United States Pacific Fleet commander Fleet Admiral Chester W. Nimitz, who was the last living U.S. Navy officer to hold the rank. With an overall length of 1,092 ft (333 m) and a full-load displacement of over 100,000 long tons (100,000 t), the Nimitz-class ships were the largest warships built and in service until USS Gerald R. Ford entered the fleet in 2017.

<i>Gerald R. Ford</i>-class aircraft carrier Class of supercarriers for the U.S. Navy

The Gerald R. Ford-class nuclear-powered aircraft carriers are currently being constructed for the United States Navy, which intends to eventually acquire ten of these ships in order to replace current carriers on a one-for-one basis, starting with the lead ship of her class, Gerald R. Ford (CVN-78), replacing Enterprise (CVN-65), and later the Nimitz-class carriers. The new vessels have a hull similar to the Nimitz class, but they carry technologies since developed with the CVN(X)/CVN-21 program, such as the Electromagnetic Aircraft Launch System (EMALS), as well as other design features intended to improve efficiency and reduce operating costs, including sailing with smaller crews. This class of aircraft carriers is named after former U.S. President Gerald R. Ford. CVN-78, was procured in 2008 and commissioned into service on 22 July 2017. The second ship of the class, John F. Kennedy (CVN-79), is scheduled to enter service in 2025.

<span class="mw-page-title-main">STOBAR</span> Aircraft carrier launch and recovery system

STOBAR is a system used for the launch and recovery of aircraft from the deck of an aircraft carrier, combining elements of "short take-off and vertical landing" (STOVL) with "catapult-assisted take-off but arrested recovery" (CATOBAR).

<span class="mw-page-title-main">Aircraft catapult</span> Device used to launch aircraft from ships

An aircraft catapult is a device used to allow aircraft to take off in a limited distance, typically from the deck of a vessel. They can also be installed on land-based runways, although this is rarely done. They are usually used on aircraft carriers as a form of assisted take off.

<span class="mw-page-title-main">A1B reactor</span> U.S. Navy aircraft carrier nuclear reactor

The A1B reactor is an aircraft carrier nuclear reactor developed by the United States Navy. It is used in Gerald R. Ford–class aircraft carriers to provide electrical and propulsion energy. The A1B is the first naval reactor produced by Bechtel Corporation, which has "performed engineering and/or construction services on more than 80 percent of [land-based] nuclear plants in the United States".

<span class="mw-page-title-main">Arresting gear</span> Cable used to rapidly decelerate an aircraft as it lands

An arresting gear, or arrestor gear, is a mechanical system used to rapidly decelerate an aircraft as it lands. Arresting gear on aircraft carriers is an essential component of naval aviation, and it is most commonly used on CATOBAR and STOBAR aircraft carriers. Similar systems are also found at land-based airfields for expeditionary or emergency use. Typical systems consist of several steel wire ropes laid across the aircraft landing area, designed to be caught by an aircraft's tailhook. During a normal arrestment, the tailhook engages the wire and the aircraft's kinetic energy is transferred to hydraulic damping systems attached below the carrier deck. There are other related systems that use nets to catch aircraft wings or landing gear. These barricade and barrier systems are only used for emergency arrestments for aircraft without operable tailhooks.

<span class="mw-page-title-main">Electromagnetic Aircraft Launch System</span> Aircraft launching system developed for the US Navy

The Electromagnetic Aircraft Launch System (EMALS) is a type of electromagnetic aircraft launching system developed by General Atomics for the United States Navy. The system launches carrier-based aircraft by means of a catapult employing a linear induction motor rather than the conventional steam piston. EMALS was first installed on the lead ship of the Gerald R. Ford-class aircraft carrier, USS Gerald R. Ford.

USS <i>Gerald R. Ford</i> Gerald R. Ford-class aircraft carrier

USS Gerald R. Ford (CVN-78) is an aircraft carrier for the United States Navy and the lead ship of her class. The ship is named after the 38th President of the United States, Gerald Ford, whose World War II naval service included combat duty aboard the light aircraft carrier Monterey in the Pacific Theater.

<span class="mw-page-title-main">CATOBAR</span> Carrier centric aircraft launch-recovery system

CATOBAR is a system used for the launch and recovery of aircraft from the deck of an aircraft carrier. Under this technique, aircraft launch using a catapult-assisted take-off and land on the ship using arrestor wires.

Since the 1970s, China's People's Liberation Army Navy (PLAN) has had ambitions to develop and operate aircraft carriers, and since 1985 has acquired four retired aircraft carriers for study; namely, the British-built Australian HMAS Melbourne and the ex-Soviet carriers Minsk, Kiev and Varyag. The Varyag later underwent an extensive refit to be converted into the Liaoning, China's first operational aircraft carrier, which also served as a basis for China's subsequent design iterations.

<span class="mw-page-title-main">Carrier-based aircraft</span> Military aircraft designed specifically for operations from aircraft carriers

A carrier-based aircraft is a naval aircraft designed for operations from aircraft carriers. Carrier-based aircraft must be able to launch in a short distance and be sturdy enough to withstand the abrupt forces of launching from and recovering on a pitching deck. In addition, their wings are generally able to fold up, easing operations in tight quarters.

INS Vishal, also known as Indigenous Aircraft Carrier 2 (IAC-2), is a planned aircraft carrier to be built by Cochin Shipyard Limited for the Indian Navy. It is intended to be the second aircraft carrier to be built in India after INS Vikrant (IAC-1). The proposed design of the second carrier class will be a new design, featuring significant changes from Vikrant, including an increase in size and displacement. An Electromagnetic Aircraft Launch System (EMALS) CATOBAR system is also under consideration. Its name Vishal means 'grand' in Sanskrit.

<span class="mw-page-title-main">Advanced Arresting Gear</span> Aircraft arresting system

The Advanced Arresting Gear (AAG) is a type of arresting gear developed by General Atomics for the U.S. Navy's newest Gerald R. Ford-class aircraft carriers. It was deployed in 2017 on the lead ship of the class, the USS Gerald R. Ford (CVN-78).

Fujian, named after Fujian province, is the first of the Type 003 class aircraft carriers. It is currently fitting out. Built for the People's Liberation Army Navy (PLAN), Fujian was launched on 17 June 2022, and is China's first fixed-wing aircraft carrier with a fully indigenous design, featuring a CATOBAR system and electromagnetic catapults.

The Type 004 aircraft carrier is a planned aircraft carrier of the People's Liberation Army Navy's aircraft carrier programme. It is intended to be an iteration on the preceding Type 003 aircraft carrier, and like the Type 003, it will feature an integrated electric propulsion system that will allow the operation of electromagnetic launch catapults. Unlike the conventionally-powered Type 003, the Type 004 will be larger and also the first Chinese carrier to feature nuclear marine propulsion, and could generate enough electricity to power laser weapons and railguns currently under development. As of 2017, China hoped to complete this carrier by the late 2020s, and indicated that up to four might be built.

Ma Weiming is a Chinese electrical engineer. He is a professor of the PLA Naval University of Engineering. He is an academician of the Chinese Academy of Engineering and holds the military rank of rear admiral. He led the development of the electromagnetic catapult system for the Type 003 aircraft carrier and the development of electromagnetic railguns. In 2017, he was awarded the Order of August First, the highest honour of the People's Liberation Army.

References

  1. ↑ Schank, John. Modernizing the U.S. Aircraft Carrier Fleet, p. 80.
  2. ↑ Doyle, Michael, Douglas Samuel, Thomas Conway, and Robert Klimowski. "Electromagnetic Aircraft Launch System – EMALS". Naval Air Engineering Station Lakehurst. 1 March. p. 1.
  3. ↑ Doyle, Michael, "Electromagnetic Aircraft Launch System – EMALS". p. 1.
  4. ↑ PEO Carriers Public Affairs (15 May 2015). "Navy Announces Successful Test of Electromagnetic Catapult on CVN 78". US Navy.
  5. ↑ "New Ford-class aircraft carrier: 25 percent more flights per day". The Christian Science Monitor . 9 November 2013. Archived from the original on 9 November 2013.
  6. 1 2 "EMALS: Learning to Launch". New England Wire. 4 May 2020.
  7. ↑ Schweber, Bill (11 April 2002). "How It Works". EDN Magazine. Retrieved 7 November 2014.
  8. ↑ Excell, Jon (30 October 2013). "October 1946 – Westinghouse unveils the Electropult". The Engineer. Retrieved 30 June 2017.
  9. ↑ Gady, Franz-Stefan (6 November 2017). "China's New Aircraft Carrier to Use Advanced Jet Launch System". The Diplomat.
  10. ↑ Yeo, Mike (9 November 2017). "China claims breakthrough in electromagnetic launch system for aircraft carrier". Defense News.
  11. ↑ Rohacs, Daniel; Voskuijl, Mark; Rohacs, Jozsef; Schoustra, Rommert-Jan (2013). "Preliminary evaluation of the environmental impact related to aircraft take-off and landings supported with ground based (MAGLEV) power". Journal of Aerospace Operations. 2 (3–4): 161–180. doi:10.3233/AOP-140040.
  12. ↑ "Chinese aircraft carrier should narrow the gap with its U.S. counterpart". english.peopledaily.com.cn. People's Daily. 18 October 2013. Retrieved 18 October 2013.
  13. ↑ "简氏:中国试飞改进型歼-15 或用于测试电磁弹射器_《参考消息》官方网站". Cankaoxiaoxi.com (in Chinese). Retrieved 30 June 2017.
  14. ↑ "China's Third Aircraft Carrier will be First to use Steam Catapults to Launch Aircraft". yibada. 12 February 2017.
  15. ↑ "China Explores Electromagnetic Carrier Launch System". AIN online. 6 July 2017.
  16. ↑ "Breakthrough to power most advanced jet launch system on China's second home-grown aircraft carrier". SCMP. 1 November 2017.
  17. ↑ "China's New Aircraft Carrier to Use Advanced Jet Launch System". The Diplomat. 1 November 2017.
  18. ↑ "China claims to have developed conventionally powered electromagnetic catapult". Jane's 360. 2 November 2017. Archived from the original on 11 November 2017. Retrieved 16 November 2017.
  19. ↑ Sutton, H. I. (15 April 2021). "China's New Aircraft Carrier Is In Same League as US Navy's Ford Class". Naval News. Retrieved 17 June 2022.
  20. ↑ 布藍 (3 August 2020). "【國產航母】003型航母進入最後組裝進程 高清航拍照曝光". 香港01 (in Chinese (Hong Kong)). Retrieved 17 June 2022.
  21. ↑ "Russia developing new launch catapults for aircraft carriers". TASS. 4 July 2018. Retrieved 14 July 2018.
  22. ↑ "Carrier Launch System Passes Initial Tests". Archived from the original on 28 September 2012. Retrieved 11 September 2018.
  23. ↑ Schank, John. Modernizing the U.S. Aircraft Carrier Fleet: Accelerating CVN 21 Production Versus Mid-Life Refueling. Santa Monica: Rand Corporation, 2005. p. 76.
  24. ↑ Joe, Rick. "Whispers of 076, China's Drone Carrying Assault Carrier". thediplomat.com. Retrieved 17 June 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.