15 Squadron was first formed at Farnborough Airfield on 1 March 1915 as a Royal Flying Corps training unit, commanded by Major Philip Joubert de la Ferté.

It was mainly equipped with Royal Aircraft Factory B.E.2cs, supplemented with a few Bristol Scouts, and moved to France on 22 December 1915, undertaking a reconnaissance role in support of the Army.

It operated in support of IV Corps during the Battle of the Somme in summer 1916, suffering heavy losses from both ground fire and German fighter aircraft.

[3] One of the officers who began his career in the squadron during this era was future Air Marshal Sir Charles Steele.

[citation needed] It reformed on 20 March 1924 at Martlesham Heath as part of the Aeroplane and Armament Experimental Establishment, mainly carrying out test flying of bomber aircraft.

After returning to the UK, the following year it re-equipped first with Bristol Blenheims and again with Vickers Wellingtons before becoming one of the first Short Stirling bomber squadrons.

In mid-1945 the squadron was involved in Operation mana dropping food to Dutch civilians and later in repatriation flights for returning allied POWs.

[citation needed] In 1947, the Lancasters were replaced with Avro Lincolns, before the squadron adopted the nuclear strike role with Boeing Washingtons in 1951.

RAF planning staff expected the squadron's twelve Buccaneer S2B aircraft to suffer attrition of one third their strength, leaving sufficient survivors, with those held back in reserve from the conventional phase, to deliver the squadron's allocation of eighteen WE.177 nuclear bombs.

Deployed to Bahrain during the build-up to Operation Desert Storm, the Squadron was given the specific brief to knock out Iraqi Air Force bases by bombing the runways.

[15][16] Relocation to RAF Lossiemouth in 1994 brought reassignment to SACLANT in the maritime strike role, armed with a variety of conventional weapons and eighteen WE.177 nuclear bombs.