Westland, Mitsubishi, and Agusta manufactured over 400 versions of the H-3 under license. Westland installed a pair of Rolls Royce Gnome H. 1400 turboshafts and a Louis Newmark Mk 31 automatic flight control system in the British Sea Kings. The RN initially ordered fifty-six HAS1 Sea Kings, with 700(S) Squadron receiving the first for test and evaluation in August 1969. Testing resulted in the more powerful HAS2, and the HAS5 with a longer cabin to accommodate the Sea Searcher radar. Westland provided the Egyptian Air Force with a twenty-one-seat Sea King utility transport, minus the external floats, called the “Commando.” The British Royal Marines also ordered this version as the HC4, which conducted extensive combat operations in the Falklands War.
Westland also produced a completely self-contained SAR helicopter that carried a crew of four, nine stretchers, a weather/search radar, smoke and flare dispensers, a flight director system with an auto hover mode, and folding blades for shipboard storage. The RAF made use of this version as the HAR Mk3 and the West German Navy as the Mk 41. Westland exported Sea King variants to India, Norway, Belgium, Pakistan, Australia, and Qatar.
On April 2, 1982, Argentinean forces invaded the Falkland Islands, touching off the Falklands War, or the Guerro Pour Los Malvinas, which lasted until June 20. Both countries possessed many of the same type of helicopters, but, despite the loss of most of their helicopters when an Exocet missile slammed into the container ship Atlantic Conveyor, the British helicopters and crews proved much more effective than the Argentineans. Operating in immoderate weather conditions, the UK machines accomplished extraordinary rescues and inflicted heavy losses on the enemy. When two Wessex HU5s crashed on Fortuna Glacier, another Wessex crew, contending with 90-mph winds and blinding snow, rescued both downed crews. During the short war, Wessex and Sea King helicopters plucked several downed aircrews from the icy waters off the Falklands, in both plane guard and SAR roles. In their baptism of fire, 20 naval Lynxes, armed with Mk 44, Mk 66, or Stingray torpedoes, or four BEA Sea Skua ASMs, scored 100 percent accuracy in the antisurface role. The Lynx HAS 2 was faster and more agile than previous British ASW helicopters and carried an updated Sea Spray search/targeting radar to locate enemy shipping and the 600-mph Sea Skua, designed to attack vessels moving at up to 50 knots. Army Lynxes, and the Chinook saved from the fire-ravaged Atlantic Conveyor, performed more than credible service in transporting troops and supplies throughout the campaign.
A number of Sea Kings were deployed during the Falklands War. They were transported to the combat zone and operated from the decks of various ships of the Royal Navy, such as the landing platform dock HMS Fearless. In the theatre, they performed a wide range of missions, from anti-submarine patrols and reconnaissance flights to replenishment operations and the insertion of special forces. Support provided by the Sea Kings in the form of transport for men and supplies has been viewed as vital to the success of the British operation. Sea Kings also protected the fleet by acting as decoys against incoming Exocet missiles, with some missions being flown by Prince Andrew, Duke of York.
Anti-Submarine Sea Kings of 820 Naval Air Squadron were embarked in HMS Invincible. With 11 HAS.5s, the squadron operated anti-submarine and search and rescue sorties with one helicopter always airborne on surface search duties. On 14 June, an 820 NAS Sea King HAS.5 was used to transport Major General Jeremy Moore to Port Stanley to accept the surrender of Argentine troops on the island. The squadron flew 1,650 sorties during the war. A Flight of 824 Naval Air Squadron embarked two Sea King HAS.2As aboard RFA Olmeda and were used to move supplies to other ships on the way south and later anti-submarine patrols. C Flight had three Sea King HAS.2As on board RFA Fort Grange which were used for replenishment duties, supplying over 2,000 tons of stores.
825 Naval Air Squadron was formed for the war with 10 Sea King HAS.2s modified as utility variants to support ground forces. The anti-submarine equipment was removed and the helicopters fitted with troop seats. Two aircraft embarked in Queen Elizabeth 2 and were later used for moving troops from QE2 to other ships, the remainder embarked in Atlantic Causeway and were used for troop movements around the islands. Embarked in HMS Hermes was 826 Naval Air Squadron with nine HAS.5s, which carried out continuous anti-submarine sorties. From the departure of Hermes from Ascension in April until the Argentine surrender, the squadron operated at least three helicopters airborne continuously for fleet protection.
On 23 April 1982, a Sea King HC4 was ditched while performing a risky transfer of supplies to a ship at night, operating from the flagship HMS Hermes. On 12 May, a Sea King operating from Hermes crashed into the sea due to an altimeter problem; all crew were rescued. On 19 May 1982 a Sea King, in the process of transporting SAS troops to HMS Intrepid from Hermes, crashed into the sea while attempting to land on Intrepid. Twenty-two men were killed and nine survived. Bird feathers were found in the debris, suggesting a bird strike, although the accident’s cause is inconclusive. The SAS lost 18 men in the crash, their highest number of casualties on one day since the Second World War. The Royal Signals lost one man and the RAF one man.
Both the British and Argentinean military lost helicopters during the war, in combat and operational accidents. Ground fire shot down British Sea Kings and Argentinean Pumas, and both sides lost helicopters when ships on which they were based sank as a result of naval combat. Argentine Pucara ground attack aircraft shot down a couple of Gazelles, killing the crews, and a friendly fire incident, when HMS Cardiff mistakenly shot down another Gazelle with a Sea Dart, cost the United Kingdom another aircraft and crew. British Sea Harriers shot down at least three Argentinean Pumas and destroyed two others plus an Agusta 109 on the ground. By the end of the conflict British forces had captured nine Bell UH-1H Hueys, two 212s, and several Pumas left on the islands.