Sea Kings were everywhere in 1982. Anti-submarine HAS5s of 820 Naval Air Squadron in HMS Invincible kept at least one helicopter airborne on surface search, flying 1,650 sorties; 826 Squadron in HMS Hermes kept at least three airborne continuously from Ascension to the surrender. 825 Squadron was formed for the war with ten HAS2s stripped of sonar and fitted with troop seats, two of them embarked in the liner Queen Elizabeth 2. Commando HC4s moved troops, guns and special forces ashore, and Sea Kings even flew as decoys against incoming Exocet missiles, some sorties flown by the then Prince Andrew.

There were heavy losses. On 19 May 1982 a Sea King carrying SAS soldiers from Hermes to HMS Intrepid crashed into the sea; 22 men died and nine survived. The SAS lost 18 men, its worst single day since the Second World War, and bird feathers in the wreckage suggested a bird strike, though the inquiry was inconclusive. On 14 June, with no other aircraft able to fly through a storm, a Sea King from the squadron commanded by Ralph Wickes-Sneyd carried Major General Jeremy Moore into Port Stanley to accept the Argentine surrender. The war also exposed the fleet’s lack of airborne early warning, and two HAS2s were fitted with Searchwater radars in an inflatable dome and flying within 11 weeks.

The RAF’s Sea King HAR3 entered service in 1978 to replace the Whirlwind and Wessex. With a lengthened cabin, extra fuel and bulged observation windows, it flew from bases around the UK and in the Falklands, day and night, for military aircrew and civilian walkers, climbers and sailors alike, until search and rescue passed to civilian contractors in 2015. Royal Navy Sea Kings did the same from Culdrose and Prestwick; both Prince Andrew and Prince William flew front-line search and rescue in the type.

Abroad the story was similar. Germany’s Mk 41, ordered in 1969 to replace the Albatross flying boat, was the first dedicated rescue Sea King. Norway’s 330 Squadron flew Mk 43s from 1973 along the whole coast, from Bodø to Sola and Banak, until the AW101 took over. Belgium’s five Mk 48s, one of them the black-painted RS-05, flew 60,000 hours and saved 1,757 people in 3,309 rescue missions before the last retired in March 2019. Canada’s Sikorsky-built CH-124s, pioneers of the “Beartrap” haul-down system for landing on small frigates, served from 1963 to 2018.

When the last conventional carrier and its Fairey Gannet radar aircraft left service in 1978, the Royal Navy lost its own airborne early warning, and in 1982 ships were sunk by low-flying aircraft the fleet could not see in time. Westland and Thorn-EMI rushed two Sea King HAS2s into service with a Searchwater radar on a swinging arm, protected by an inflatable bag that could be lowered beneath the fuselage in flight and raised for landing. They flew within 11 weeks and joined HMS Illustrious after the fighting.

Production AEW2s entered service with 849 Naval Air Squadron in 1985. They were upgraded to the ASaC7 (Airborne Surveillance and Control Mk 7), with Searchwater 2000 able to track up to 400 targets and a Link 16 data link, and flew from HMS Ark Royal in the 2003 invasion of Iraq. They outlived every other British Sea King, the last seven serving until 2018, when the Merlin-mounted Crowsnest system replaced them.

• Sikorsky SH-3A/D/G/H: US Navy anti-submarine and utility versions; VH-3A/D presidential transports; Agusta, Mitsubishi and United Aircraft of Canada (CH-124) licence builds.
• HAS1: first Royal Navy anti-submarine version, 56 built.
• HAS2: more powerful Gnomes and a six-bladed tail rotor; some converted for AEW.
• AEW2 / ASaC7: airborne early warning with Searchwater, later Searchwater 2000; 13 in the final fleet.
• HAR3 / HAR3A: RAF search and rescue, 19 plus six.
• HC4 / Commando: assault transport for up to 28 troops; 42 HC4s for the Royal Navy, Commandos for Egypt and Qatar.
• HAS5 / HAS6: improved anti-submarine versions with Sea Searcher radar and new sonar processing; HAR5 and HU5 rescue and utility conversions.
• Mk 41: German Navy rescue, later armed with Sea Skua.
• Mk 42, 42A, 42B, 42C: Indian Navy anti-submarine, anti-ship (Sea Eagle) and utility versions.
• Mk 43: Norwegian rescue.
• Mk 45: Pakistan Navy, with Exocet.
• Mk 47: Egyptian Navy.
• Mk 48: Belgian rescue.
• Mk 50: Royal Australian Navy.

One of the few published comparisons comes from Belgium. In 2020 its defence ministry said the Sea Kings retired in 2019 had cost about €5,000 per flight hour, while the NH90s that replaced them cost more than double, about €12,000. An old helicopter with simple, well-understood systems and a mature spares network can be cheap to run even when its airframe hours are high, as Canada found: its crews told Vertical that serviceability improved in the type’s fifth decade thanks to techniques such as vibration analysis.

The other side of age is availability. After the 1998 US sanctions India had 60 per cent of its fleet grounded for lack of spares, and keeping Sea Kings flying in Ukraine depends on donated airframes and parts. The figure in the table is a single reported number, not a universal cost.