STOBAR

The Russian aircraft carrier Admiral Kuznetsov with a ski-jump takeoff ramp for STOBAR

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

Aircraft launch under their own power using a ski-jump to assist take-off (rather than using a catapult). However, these are conventional, rather than STOVL aircraft, and thus require arrestor wires to land on the ship. The STOBAR system is simpler to build than CATOBAR. As of 2015, it has only been used regularly on Russian, Indian, and Chinese carriers.

Advantages

Compared to CATOBAR, STOBAR is less expensive to develop. It is easier to operate than a CATOBAR configuration which requires large number of operators to launch the aircraft. Lack of any moving parts in ski-jump makes it less expensive to maintain the launch system.^[1][2] It does not require any additional system to generate force required to launch the aircraft unlike CATOBAR where an external force is needed to be generated either from steam catapult^[3] or Electromagnetic Aircraft Launch System (EMALS)^[4] to launch the aircraft.

Limitations

Construction of the ski-jump on INS Vikramaditya

One major limitation of STOBAR configuration is that it only works with fighter aircraft that have a high thrust to weight ratio such as Su-33 or MiG-29K and thus limits the kind of aircraft that can be operated from the carrier. It is not known what restrictions ski-jump takeoff implies on maximal aircraft weight. According to some sources, in order to become airborne, the aircraft may be required to limit its weaponry and fuel package in order to reduce the launch weight of the aircraft.^[1][5] However according to other sources,^[6] the Super Hornet can take-off from a ski-jump with a significant weapons load. Using ski-jump can limit the ability to conduct sorties faster on STOBAR aircraft carrier.^[7] STOBAR carriers must maintain a speed of 20kn-30kn in order to generate wind speed required on deck which is essential for conducting aircraft launch operations.^[8]

List of STOBAR aircraft

HAL Tejas (NP-1) short take-off during test flight.

• HAL Tejas - The Naval Tejas is a variant of HAL Tejas Developed for Indian navy. A prototype (np-1) is currently under flight testing.^[9][10][11]
• Mikoyan MiG-29K - currently active with the Indian Navy and the Russian Navy.
• Shenyang J-15 - operated by People's Liberation Army Navy on Liaoning^[12]
• Sukhoi Su-33 - Developed from Su-27 and only operated by the Russian Navy.

Users

As of October 2018, three countries currently operate STOBAR type carriers; Russia is the only country that has built a STOBAR ship for operation, while both India and China have procured STOBAR ships that were built by Russia and have had them converted for their own use. However, both India and China are in the process of building their own STOBAR carriers.

Active STOBAR Aircraft Carriers

Class	Image	Origin	No.of ships	Propulsion	Displacement	Operator	Aircraft Carried	Notes
Admiral Kuznetsov		Soviet Union	1	Steam turbine	58,000 tons	Russian Navy	Su-33 MiG-29K Ka-27
			1			People's Liberation Army Navy	J-15 Z-18
Kiev		Soviet Union	1	Steam turbine	45,500 tons	Indian Navy	MiG-29K Ka-31 Sea King	Built as STOVL carrier and converted to STOBAR
Type 001A		China	1	Steam turbine	55,000 tons	People's Liberation Army Navy	Undergoing sea trials[13]	Upgraded Kuznetsov type design
Under Construction
Vikrant		India	1	Gas turbine	40,000 tonnes	Indian Navy

References