To finally close the Mid-Atlantic gap, or "Black Gap", a space in which Axis submarines could prey of Allied shipping historically out of reach of MPAs, the British Royal Air Force, the Royal Canadian Air Force, and the US Army Air Forces introduced the American Consolidated B-24 Liberator bomber, which had a very long range for the era.Green 1975, p. 85.Winchester 2004, p. 57. The B-24 was also used at the basis for the PB4Y-2 Privateer, a dedicated MPA variant adopted in large numbers by the US Navy, which saw service late on in the Pacific theatre.Bridgeman 1946, pp. 217–218.Swanborough and Bowers 1990, p. 106.
