[WWII] Consolidated B-24 Liberator heavy bomber (USA)

[copeab]

Consolidated B-24 Liberator heavy bomber
Copyright 2010 by Brandon Cope

The B-24 Liberator was the second of America's wartime heavy bombers, entering production in June 1941, with over 18,000 eventually being built. While it was more versatile than the more famous B-17 Flying Fortress (p.W:DF85) it was not as popular. The B-24 could fly farther, faster and higher than the B-17 and do it with a greater load. However, the B-24 was a harder plane to fly and was not nearly as resistant to battle damage; in particular it's smaller wing was relatively easy to destroy for a plane it's size. Despite this, the B-24 had a slightly lower loss rate than the B-17.

The B-24 was extensively used in the Pacific and Asia, where it's long range (for patrols over the ocean) and high altitude (for flying The Hump in the China-Burma-India theatre) were assets. Aside from it's role as a long range strategic bomber, it was also used for photo reconnaissance, maritime reconnaissance, antisubmarine and transport roles. The British used a few to supply SOE agents and resistance movements in Europe.

The Liberator had four engines mounted on a high wing and had two distinctive "barn door" rudders. It also used tricycle landing gear. The belly turret was fully retractable, but affected stability negatively when extended. The -J model entered production in 1943 and addressed a vulnerability to frontal attacks by adding a nose turret. Some 6,700 were built.

The B-24J has a crew of ten: Pilot, co-pilot, navigator/radio-operator, bombardier and six gunners (ventral, dorsal, nose and tail turrets, two hand aimed waist guns). The dorsal and ventral turrets were capable of full rotation, the nose and tail turrets were partial rotation. The Liberator uses 161 gallons of aviation fuel per hour at routine usage.

Subassemblies: Heavy Bomber chassis with Good streamlining +5, Heavy Bomber Wings +4, 4¥Small AFV Engine Pods +3, 2¥full rotation Medium Weapon turrets +1, 2¥partial rotation Medium Weapon Turrets +1, three retractable wheels +2.
Powertrain: 4¥895-kW aerial HP turbo-supercharged gasoline engines [Pods] with 4¥895-kW props, and 2,814-gallon self-sealing fuel tanks [Wings and Body], 4,000-kw batteries
Occupancy: 10 CS Cargo: 20.

Armor
All: 3/5
Pilot/Co-Pilot/bombardier/navigator: B +0/30
Dorsal/Ventral Turret Gunners: FB 0/+30
Nose/Tail Gunners: F 0/+30
Waist Gunners: RLB 0/+30

Armament
2¥Long Aircraft HMG/Browning M-2 [Tur#1-4:F] (400 rounds each) *
Long Aircraft HMG/Browning M-2 [Body:R,L] (400 rounds each)
10¥500-lb Bombs [Body:U]
* linked to fire as pair in each turret

Equipment
Body: Large radio receiver and transmitter, backup driver option, precision navigation instruments, IFF, autopilot, advanced bombsight, 8,800-lb bomb bay. Wings: 4,000-lb hardpoint each. Turrets: Universal mounts

Statistics
Size: 64'x110'x18'
Payload: 12 tons
Lwt: 28 tons
Volume: 1,840
Maint.: 20 hours
Price: $101,900

HT: 9.
HP: 1,100 [body], 413 [each wing], 150 [each pod], 75 [each turret], 100 [each wheel]

aSpeed: 300
aAccel: 4
aDecel: 10
aMR: 2.5
aSR: 2
Stall: 105

Design Notes
Design speed was 323 mph. The historical speed has been used, as well as the actual wing area (1,048 square feet). Wing cost, weight and HP was divided by two. Loaded weight was decreased by 5.5%. Historical cost was $298,000.

aSR was reduced by 1. There should be a -1 to Piloting rolls for precision flying, -3 if the belly turret is extended.

The stats above assume a 5,000-lb bombload and that the 450-gallon auxiliary wing tanks are empty. Maximum bombload was 12,800 lbs and maximum takeoff weight was 35.5 tons.

Up to 800 gallons of fuel in auxiliary tanks could be fitted in the bomb bay if required.

Variants
The initial B-24A (1941) was primarily used by the British, who dubbed it the Liberator I. It mounted a single Browning .303 MG (Aircraft LMG) in each of the nose, dorsal, ventral and two waist positions (the American planes mounted a single Browning .50-cal in the nose, belly and both waist positions). Two .30-cal guns were also in the tail. Maximum bombload was 4,000 lbs. Top speed was 293 mph. Some carried a pack of four 20mm Hispano cannons (20mm Long Aircraft AC) under the forward fuselage for anti-sub duties. Only 29 were built (20 of which went to the RAF).

The Liberator II (1942) only served with the British. It mounted dorsal and tail power turrets, each with four Browning .303's, as well as single guns in the nose, ventral and both waist positions. Fuel tanks were self-sealing. Top speed was 263 mph due to the increased drag of the turrets. Some 140 were built.

The LB-30 (1942) were 75 planes similar to the Liberator II, but used by the US (they were requisitioned from the British order after the attack on Pearl Harbor). They saw operational use in Java, Panama and the Aleutians early in the war. They differed from the Liberator II's primarily in armament, mounted two Browning .50's in the upper turret, two hand operated .50-'s in the tail and single .50's in the nose, belly and waist locations. any were converted into unarmed transports; 29 were eventually returned to the British.

The B-24C (1941) added the turbo-supercharged engines of the lone XB-24B and added self-sealing tanks. Powered turrets were installed in the dorsal and tail positions, each with .50-cal Browning M-2's. It retained the single nose, waist and ventral guns. Only nine were built.

The B-24D (1942) was the first major production of the Liberator, with 2,738 being built. The armament was similar to the -C, but no ventral or waist guns were initially provided. The 77'th plane added a ventral turret with two guns; it was retractable and aimed via periscope. However, the sighting system was highly unreliable and after 287 planes the single ventral gun was reinstalled. Eventually, a manned ball turret like that on the B-17E was installed for ventral defense. The two waist guns were also later restored. During the production run, two additional nose guns were installed, although the bombardier could only operate one at a time. Bombload was increased to 8,800-lbs internal with two 4.000-lb wing hardpoints. It introduced 450 gallon reserve fuel tanks in the wings, but they could not be used directly -- the fuel had to be pumped into a main wing tank.

The 801 B-24E's (1942) were similar to the late-model -D's, but the ventral turret was replaced by a single machine-gun. Most were retained as trainers and only a small number saw combat.

The B-24H (1943) were generally similar to the -D, except they installed a powered nose turret (with two Browning .50's) in an effort to defend against frontal attacks. 3,100 were built. 430 of the very similar B-24G were built.

The B-24L (1944) was an attempt to save weight (while the plane's weight had increased steadily, engine power had not(. The ventral turret was replaced with two hand-aimed guns. The rear turret was unpowered. Almost 1,700 were constructed.

About 2,500 of the B-24M (1944) were built, significantly differing from the -G only in having an unpowered tail turret. Very few saw service and a few built afer June 1944 had only one flight -- from the factory to the scrap yard.

The F-7A & B were 178 aircraft modified to carry six recon cameras (nose and bomb bay for the -A, all in the bay for the -B). Armament was retained. Most were used in the China-Burma-India theater.

The PB4Y-1 were "navalized" Liberators used by the US Navy for recon and anti-sub duty. They were originally based on the -D, but production included all the major land-based variants.

The C-87 (1942) was a transport version, carrying 25 men. The first 73 were converted from existing aircraft and an addition 287 were built from scratch. The RAF received 24. The six C-87A's were "executive" transports with only 16 seats.

The C-109 was a tanker version built from 208 existing -J and -L airframes, intended to supply B-29's to be based in China (a need that evaporated with the capture of the Marianas Islands). It was normally unarmed and carried 2,900 gallons of additional fuel in eight fuselage tanks..

[PPoS]

Finally ! Thank you so much for posting this.

[copeab]

Originally Posted by PPoS

Finally ! Thank you so much for posting this.

It wasn't a design I looked forward to because I knew the write-up would be a lengthy one (it could have been longer than it turned out). It also didn't help that sources couldn't agree on some key numbers.

I have no idea which unpublished WWII book the plane had been reserved for (I vaguely remember an Air War book on the wishlist, which seems the most likely).

[Phaelen Bleux]

I had thought to work out this design as well, and printed off materials to get started. That was in 2005. You did a much better job than I would have, so I thank you as well!