The Consolidated Liberator II was the final version of the aircraft to be build as part of the original French order for the LB-30. Originally the RAF had ordered 140 Liberator IIs, but the first was destroyed while being tested, delaying the entire program. Deliveries resumed on 8 August 1941, but were then disrupted again by the Japanese attack on Pearl Harbor. The USAAF took over 75 of the aircraft under the designation LB-30 and rushed many of them into combat in the Pacific. The RAF was left with 64 Liberator IIs, although another 23 of the LB-30s were later returned to Britain as American production increased.
The Liberator II was the first version of the aircraft to feature the lengthened nose that would become standard on all later aircraft. This extension, which increased the length of the aircraft from 63ft 9in to 66ft 4in, was originally made for purely aesthetic reasons, but as the war developed, and the amount of equipment carried on aircraft increased, the extra space proved to be very valuable. The Liberator II was powered by the commercial R-1830-S3C4-G engine, which lacked the turbosupercharger used on USAAF aircraft. The engines powered Curtiss Electric propellers with longer hubs than on earlier versions of the aircraft. The aircraft carried fourteen .303in machine guns – one in the nose, one in a tunnel hatch, two in each waist position, and four each in Boulton-Paul power operated tail and dorsal turrets.
The Liberator II served in an unusually wide range of roles. The first three squadrons to receive it were Nos. 108, 120 and 511 in 1941. No.108 Squadron used the aircraft on a mix of bombing and supply drop missions over the Balkans, No.120 Squadron used it for anti-submarine patrols and No.511 Squadron provided a transport service between Gibraltar and the United Kingdom.
In 1942 No.159 Squadron and No.160 Squadron began bombing operations with the Liberator II from bases in the Middle East, before moving on to the Far East while Coastal Command used the type to equip No.224 Squadron.
In 1943 No. 148 Squadron began to use the Liberator to drop supplies to partisans across Greece, Albania and Yugoslavia, while No.178 Squadron began to use the Liberator II on bombing missions in the Mediterranean. Finally in 1944 Nos.231 and 246 Squadrons received the Liberator II and used it for transport duties.