The initial production version of the Liberator was the B-24A, 38 examples of which had been ordered in August of 1939. Serials were 40-2349/2386.
With the fall of France, the order for the first 20 of these planes (40-2349/2368) was diverted from the USAAC for delivery to the Royal Air Force under the designation LB-30B.
The twenty LB-30Bs were delivered to the RAF in mid-1941 as Liberator I and were serialed AM910/AM929. They were powered by R-1830-33 engines. Like the YB-24s before them, the B-24As were delivered to the RAF at Montreal in Canada for transfer to England. The LB-30Bs differed from the USAAF B-24As in having equipment that was specifically intended to meet British requirements. For example, they were delivered with the standard RAF defensive armament of six flexible 0.30-inch Browning machine guns, two in the tail, one in the nose, one in each waist position, and one in the belly position.
The RAF Liberator I was the first of the type to see combat. The long range and heavy bombload made the Liberator I a natural choice for RAF Coastal Command for use in its battles against the U-boat menace. Upon arrival in England, they were extensively modified to make them suitable for the antisubmarine role. They were equipped with early versions of ASV radars, which included a thicket of Yagi aerials protruding from the nose and the wings, four stickle-back mast antennae sticking upward from the ventral fuselage, and a set of towel-rail type antennae attached to the sides of the rear fuselage. The aircraft looked not unlike a flying porcupine. For attacks on surfaced U-boats, Liberator Is were fitted with a pack for four forward-firing 20-mm Hispano cannon underneath the forward fuselage. These modifications were carried out by Heston Aircraft Ltd. The normal operating crew was seven.
The Liberator I first equipped No. 120 Squadron of RAF Coastal Command based at Nutt's Corner, Belfast in June of 1941. With a normal operating range of 2400 miles, the Liberator I nearly doubled the effective range of Britain's maritime reconnaissance forces. They were the first machines with the ability to close the Atlantic Gap, where U-boats had previously been able to operate with immunity from air attack.
The Liberator Is served with No. 120 Squadron until December of 1943, when they were replaced by later Liberator marks. Liberator Is are credited with at least 8 U-boat kills.
Three of the Liberator Is (AM915, AM918, and AM920) were operated by the BOAC to carry priority passengers and to ferry crews across the Atlantic. On January 24/25, 1942, AM918 with civil registry G-AGDR flew nonstop from Hurn to Cairo. However, on its return trip on February 15, it was shot down by mistake by Allied fighters. Surviving examples were returned to the RAF in January of 1945. AM920 was converted to civilian configuration for BOAC in 1946 under the registration G-AHYB
After the diversion of serials 40-2349/2368 to the RAF as LB-30Bs, the USAAF eventually made up the deficit by having 20 additional Liberators delivered. By this time, the production model was the B-24D. However, these B-24Ds were allocated the same serials (40-2349/2368) that were used by the diverted B-24As. Once again the same serial numbers were allocated to two different batches of aircraft, which led to an endless amount of confusion.
Of the remainder of the B-24A order, only 40-2369/2377 were destined to actually be built as B-24As. The rest (40-2378/2386) were delivered as B-24Cs.
Liberator I AM927 was damaged in transit and was never delivered to the UK as were the other LB-30Bs. It was returned to Consolidated for repair. During rebuild, an extra four feet was added to the nose of the aircraft. It was then operated as a company plane. It was later used as a transport carrying USAAF insignia but still with its original RAF serial on the tail. For a while after the war, this plane was flown by the Continental Can Company under the civilian registry N1503, until it was acquired by the Confederate Air Force (now known as the Commemorative Air Force) to be operated as a flying museum. It now flies with the civilian registry of N12905, painted as a B-24D carrying the name Diamond Lil
Specification of the Consolidated Liberator I:
Four Pratt & Whitney R-1830-33 (S3C4-G) Twin Wasp fourteen-cylinder air-cooled radials rated at 1200 hp for takeoff and 1000 hp at 14,500 feet. Performance: Maximum speed 292.5 mph at 15,000 feet. Cruising speed 228 mph. Landing speed 92 mph. Service ceiling 30,500 feet. An altitude of 10,000 feet could be attained in 5.6 minutes. Range was 2200 miles with a 4000 pound bombload. Maximum range was 4000 miles. Weights: 30,000 pounds empty, 39,350 pounds gross, 53,600 pounds maximum. Dimensions: Wingspan 110 feet 0 inches, length 63 feet 9 inches, height 18 feet 8 inches, wing area 1048 square feet. Delivered with the standard RAF defensive armament of six flexible 0.30-inch Browning machine guns, two in the tail, one in the nose, one in each waist position, and one in the belly position. An additional four 20-mm cannon were installed in a belly pack.