Sea Skua

The Sea Skua is a British lightweight short-range air-to-surface missile (ASM) designed for use from helicopters against ships. It is primarily used by the Royal Navy on the Westland Lynx. Although the missile is intended for helicopter use, Kuwait employs it in a shore battery and on their Umm Al Maradem (Combattante BR-42) fast attack craft.

The British Aircraft Corporation (BAC) began development of the weapon in May 1972. The British Government authorised its production in October 1975. At the time, the missile was known as CL834.^[1] In November 1979 the first launches took place at the Aberporth Range in Cardigan Bay. Three missiles were launched from the ground and three by helicopters. Further tests were made and in July 1981, full-scale production was ordered of the new missile, now called "Sea Skua".^[2]

Design

Sea Skua missile

With the missile weighing only 320 pounds (150 kg) at launch, a Lynx helicopter can carry up to four (two on each wing pylon). The booster is a Royal Ordnance (now Roxel UK) "Redstart" steel body, while the sustainer is a Royal Ordnance "Matapan" light alloy body. The missile flies at high subsonic speed to a range of up to 15.5 miles (24.9 km). The official range is declared to be 15 km, but this is widely exceeded. The missile has two sensors: a semi-active radar homing system by Marconi Defence Systems, and a Thomson-TRT AHV-7 radar altimeter (which is also used by the Exocet missile), built under licence by British Aerospace Defence Systems.^[2]

It can be set to travel at one of four pre-selected heights, depending on the surface conditions. Near the target, the missile climbs to a height at which it can "acquire" the target. The launching helicopter illuminates the target with its radar (originally the specially developed Ferranti Seaspray in the case of the Lynx), and the missile's homing head homes in on the reflected energy. On impact it penetrates the hull of a ship before detonating the 62 pounds (28 kg) blast fragmentation warhead. A semi armour piercing (SAP) warhead is also available; this contains 9 kilograms (20 lb) of RDX, aluminium and wax. The fuze is an impact-delayed model.^[2]

The illuminating radar aboard Lynx helicopters is the GEC-Ferranti Seaspray I band, which weighs 64 kilograms (141 lb), a power of 90 kW, two modes (three in the improved model) and a 90° observation field. The Seaspray Mk. 3 had a rotating antenna with a 360° field of view. It is capable of operating in a track while scan (TWS) mode. The missile flight ends after 75–125 seconds, during which time the helicopter can manoeuver at up to 80° from the missile path.^[2]

Service

In addition to serving with the United Kingdom, the Sea Skua has been exported to Germany (where it will be replaced from 2012 onwards), India, Kuwait, and Turkey. It was generally preferred to the similar rival, the French-built AS 15 TT, even though the two missiles had similar performance. The guidance of AS-15TT was radio-command, and it required the Agrion 15 radar, unlike the more flexible British missile. Sea Skua's success in active service and its adoption by the Royal Navy resulted in considerable success in the international market.^[3]

Falklands War

Sea Skuas were launched eight times during the Falklands War, sometimes in extremely bad weather, and scoring a very high hit rate. Four were used against the 800 ton patrol boat/rescue tug ARA Alférez Sobral, fired by two Lynx helicopters from HMS Coventry and HMS Glasgow. Two struck the patrol boat on the bridge, one hit the ship's fibreglass sea boat, and one passed over the ship.^[4] Extensive damage was inflicted and eight crewmen (including the captain) were killed, but the ship was not sunk and returned to Puerto Deseado unaided. Another four Sea Skuas were used to destroy the wrecks of the cargo ship Río Carcarañá (8,500 grt) and the patrol boat Río Iguazú.

First Gulf War

During the Gulf War, six naval Lynx helicopters were deployed to the Gulf on four frigates and destroyers of the Royal Navy. On 24 January 1991 one Lynx engaged and sank two Iraqi minesweepers near Qurah Island. A third was scuttled.

A larger engagement took place on 29 January 1991. A force of seventeen Iraqi landing craft and escorting fast attack craft and minesweepers was detected moving south near Failaka island, as part of the Iraqi attack which resulted in the Battle of Khafji. Two vessels were sunk by Sea Skuas fired by four Lynx helicopters. The remaining vessels were damaged, destroyed or dispersed by American carrier-based aircraft and Royal Navy Sea King helicopters.

The next day, another convoy of three Polnocny class landing ship, three TNC-45 fast attack craft (taken over by Iraq from the Kuwaiti Navy) and a single T-43 minelayer, was detected in the same area. Sea Skuas fired from four Lynx helicopters destroyed the three fast attack craft, and damaged the minesweeper and one landing ship; the landing ship was later destroyed by RAF Jaguars.

During several engagements in February, Lynxes with Sea Skuas destroyed a Zhuk class patrol boat, a salvage vessel and another Polnocny class landing ship, and damaged another Zhuk patrol boat.^[5]

Royal Malaysian Navy service

The Sea Skua entered service with the Royal Malaysian Navy as part of the package for the purchase of six AgustaWestland Sea Lynx 300 helicopters. The missiles supposedly cost RM104 million.

On 16 March 2006 the Royal Malaysian Navy test fired the Sea Skua missile as part of a contractual Firing exercise. The missile was fired eight miles down range from the 40m Surface Target Barge. The Sea Skua failed to hit its target and failed to explode. The fault was believed to have been traced to a faulty connecting pin wire that ignites the rocket motor. The missile fell into the sea, and was not recovered. The Royal Malaysian Navy ordered Matra Bae Dynamics (MBDA) to take back the missiles to conduct system checks, and re-tested.

On 12 February 2008, the Royal Malaysian Navy successfully conducted a second firing. The missile was fired from maximum range and hit a surface target.

Future

Sea Skua is planned to be replaced in UK service by the Sea Venom.^[6]

Operators

Map with Sea Skua operators in blue

An inert Sea Skua on the deck of a Kuwaiti ship

Four Sea Skua canisters can be seen on the stern of Kuwaiti FAC Al Fahaheel (P3721) in May 2013

Current operators

 Brazil

 Germany

 India

 Kuwait

 Malaysia

Royal Malaysian Navy

 Pakistan

 Republic of Korea

Republic of Korea Navy

 Turkey

 United Kingdom

Royal Navy, Fleet Air Arm

See also

• Penguin (missile)
• Skua - the bird the missile is named after
• AS 15 TT
• Exocet

Notes

Sources

External links

Wikimedia Commons has media related to Sea Skua.

• Video of a Malaysian Sea Skua live firing test

Guided missiles of the United Kingdom
Air-to-air	ASRAAM Fireflash Firestreak Red Dean Red Top SRAAM/Taildog Skyflash
Air-to-surface	ALARM Brimstone Lightweight Multirole Missile Martel1 Sea Eagle Sea Skua Storm Shadow1 Sea Venom1 SPEAR 3
Surface-to-air	Bloodhound Blowpipe CAMM Javelin Rapier Seacat Sea Dart Seaslug Sea Viper Sea Wolf Starburst Starstreak Tigercat Thunderbird
Surface-to-surface	Swingfire Malkara2 UB.109T Vigilant
Nuclear	Blue Steel Blue Streak Blue Water Green Cheese
1 Anglo-French   2 Anglo-Australian