Beaufighters and Shackletons (1946–1971)

On 1 October 1946, No. 254 Squadron at RAF Thorney Island was renumbered to No. 42 Squadron. Equipped with Bristol Beaufighter, it was a strike unit in RAF Coastal Command until disbanded on 15 October 1947.^[2][12]

On 28 June 1952, No. 42 Squadron was reformed at RAF St. Eval, Cornwall, flying Avro Shackleton MR.1s in the maritime reconnaissance role.^[12] In 1954, the squadron began to re-equip with the Shackleton MR.2.^[14] On 11 January 1955, two squadron Shackleton MR.2s (WG531 and WL743) disappeared while operating near Fastnet Rock.^[15] No. 42 Squadron Shackletons used to regularly visit RAF Khormaksar in Aden before the Aden Emergency, with it undertaking colonial policing.^[16][17]

No. 42 Squadron relocated to RAF St. Mawgan in October 1958.^[14] In 1961, the squadron deployed to Jamaica to provide support for relief operations after Hurricane Hattie struck the Caribbean and British Honduras.^[18] It further converted to the Shackleton MR.3 in December 1965.^[14] In 1966, No. 42 Squadron deployed to Mahajanga, Malagasy Republic, to take part in the Beira Patrol which enforced the blockade of the port of Beira in Mozambique to prevent oil shipments to Rhodesia.^[18]

Nimrods (1971–2011)

In April 1971, No. 42 (Torpedo Bomber) Squadron began to convert to the Hawker Siddeley Nimrod MR.1.^[2][12]

No. 42 (TB) Squadron were the first Nimrod unit to arrive at Wideawake Airfield, Ascension Island, when XV244 and XV258 landed on 6 April 1982 shortly after the invasion of the Falkland Islands.^[19] In October 1984, one of No. 42 (TB) Squadron's crews won the Fincastle Trophy at RAAF Base Edinburgh, South Australia.^[19] On 29 August 1985, Nimrod MR.2 XV229 helped locate the wreck of Virgin Atlantic Challenger.^[19]

In June 1990, No. 42 (TB) Squadron won the Fincastle Trophy once again, this time at CFB Greenwood, Nova Scotia.^[19] In October 1990, the squadron deployed its crews to Seeb International Airport, Oman, and later to RAF Akrotiri, Cyprus, in January 1991 as part of Operation Granby.^[20] Nimrod MR.2 XV244 (Battle Star 42) was credited with 14 mission markings and four ship kills while deployed.^[21] One of the squadron's crews were credited with having achieved the highest number of assisted kills – six, achieved operating in a High Air Threat environment.^[21]

Disbanded as a front-line unit in October 1992, it was later reformed as No. 42 (Reserve) Squadron at RAF Kinloss, Moray, taking over from No. 236 OCU as the Nimrod Operational Conversion Unit (OCU).^[20]

No. 42 (R) Squadron made the Nimrod's last visit to Gibraltar on 20/21 March 2010 as part of Operation Active Endeavour.^[22] The squadron flew its last Nimrod MR.2 flight on 30 March 2010 with XV232 visiting Rockall, St. Kilda, RAF St. Mawgan, RAF Valley and RAF Lossiemouth.^[22] It was originally expected that No. 42 (R) Squadron would serve as the OCU for the BAE Systems Nimrod MRA.4, however it was cancelled as part of the 2010 Strategic Defence and Security Review,^[21] with No. 42 (R) Squadron formally disbanding alongside the other Nimrod units on 26 May 2011.^[23]

Poseidon and Wedgetail OCU (2023–present)

The unit was reformed as No. 42 (Torpedo Bomber) Squadron on 21 September 2023 at RAF Lossiemouth, Moray. The squadron is the Operational Conversion Unit for both the Boeing Poseidon MRA1 and Boeing Wedgetail AEW1. No. 42 (TB) Squadron's first Poseidon sortie was flown on 26 September 2023.^[11]