Mid-Atlantic gap

The Mid-Atlantic gap was an area outside the cover by land-based aircraft; those limits are shown with black arcs (map shows the gap in 1941). Blue dots show destroyed ships of the Allies

The Mid-Atlantic gap is a geographical term applied to an undefended area of the Atlantic Ocean during the Battle of the Atlantic in the Second World War. The region was beyond the reach of land-based RAF Coastal Command antisubmarine (A/S) aircraft. This resulted in heavy merchant shipping losses to U-boats. It is frequently known as The Black Pit[citation needed], as well as the Atlantic Gap, Air Gap, Greenland Gap, or just "the Gap". 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.