Douglas B-18 Bolo

The Douglas B-18, later given the popular name ‘Bolo’, was designed in response to a 1934 request for a bomber to replace the Martin B-10 and B-12, which at the time made up the bulk of the American bomber force. The new aircraft was to have twice the range and twice the bombload of the existing aircraft. Boeing’s competing design lost out when the prototype crashed but was sufficiently advanced to be ordered into production as the B-17 Flying Fortress, but the B-18 won the initial contract.

Based on Douglas’ successful DC-2 airliner, the B-18 had lengthened wings and a redesigned nose structure to accommodate the bombardier’s equipment. The fuselage was also redesigned to be deeper, with the wings mounted amidships, in order to provide space for the bombs to be carried in an internal bomb bay. Three machine guns were also mounted to give some defence against enemy interceptors.

The B-18 had an undistinguished war career. During the attacks on Pearl Harbor and the Philippines, dozens of the B-18s were destroyed on the ground by Japanese bombing, with none even getting airborne in response. Thereafter the remaining aircraft played only a very minor role in the conflict, mainly being used as transports or squadrons ‘hacks’.

In the Atlantic and Caribbean theatres the B-18 enjoyed some limited success. Here the bomber was converted into an anti-submarine aircraft, being fitted with radar and Magnetic Anomaly Detection (MAD) gear. A few German U-boats were sunk by B-18s operating this role during late 1942.