Mid-Atlantic Gap

The Mid-Atlantic Gap is a geographical term attributed to an undefended area beyond the reach of land-based RAF Coastal Command antisubmarine (A/S) aircraft during the Battle of the Atlantic in the Second World War. It is frequently known as The Black Pit, as well as the Atlantic Gap, Air Gap, Greenland Gap, or just "the Gap". This resulted in heavy merchant shipping losses to U-boats. The gap was eventually closed in May 1943, as growing numbers of VLR Liberators (Very Long Range models) and escort carriers became available, and as basing problems were addressed.

RAF Coastal Command, when it was created in 1936, was given responsibility for A/S (or ASW) patrol. It was equipped only with small numbers of short-ranged aircraft, the most common being the Avro Anson (which was obsolescent by the start of World War II) and Vickers Vildebeest (which was obsolete); for a time, shortages of aircraft were so severe, "scarecrow patrols" using Tiger Moths were even employed.Bomber Command routinely got higher priority for the best, longest-ranged aircraft. Only as Bomber Command transitioned to four-engined aircraft did Coastal Command receive the castoffs, such as Vickers Wellingtons, which finally had adequate range for A/S patrol. Moreover, Coastal Command's motley assortment of Ansons, Whitleys, and Hampdens were unable to carry the standard 450 lb (205 kg) depth charge; that needed Wellingtons or Sunderlands. (The other aircraft capable of carrying it, the Avro Lancaster, was Bomber Command's crown jewel.)

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