Consolidated B-24 Liberator B-24D

The B-24D was the first Liberator version built on a large scale. Ordered between 1940 and 1942, it was essentially a B-24C with more powerful R-1830-43 engines, entering US service in early 1942 with turbochargers and increased fuel capacity. Three additional .50 in machine guns raised defensive armament to ten guns. At 59,524 lb maximum take-off weight it was one of the heaviest aircraft in the world, comparable with the British heavies.

Its ventral armament changed repeatedly: early aircraft carried a remotely operated, periscopically sighted Bendix turret that proved unsatisfactory and was dropped after the 287th aircraft; later machines reverted to the manual tunnel mounting with a single gun, itself replaced by the Sperry ball turret, made retractable because the Liberator's fuselage sat very close to the ground.

The B-24D was the Liberator of the anti-submarine campaign and of the type's hardest missions. On 1 August 1943, 177 B-24s carried out the second attack on the Ploiesti refineries — Operation Tidal Wave — the costliest mission of the aircraft's career. The B-24D also equipped the Carpetbaggers: aircraft painted in glossy black anti-searchlight finish that from August 1943, working with the OSS, supplied resistance forces across occupied Europe. Other retired B-24Ds served as 2nd Division assembly ships, painted in stripes or checks to marshal formations. A total of 2,696 were built: 2,381 by Consolidated San Diego, 305 by Consolidated Fort Worth and 10 by Douglas Tulsa. In British service it was the Liberator Mk.III.