Wuzak
9th January 2009, 03:52
With the discussions we have had in the past about deleting the defensive armament of bombers and the effect that would have on performance I wondered how a B-24 would fare.
Luckily Consolidated had done the right thing and built a model without defensive armament. It was the C-87 Liberator express.
The first C-87 was based on the B-24D, converted from a damaged bomber. The B-24D didn't have the amount of defensive armament that later models did, but it did have some. So the performance numbers surprised me a little:
B-24D
Four Pratt & Whitney R-1830-43 fourteen-cylinder turbosupercharged air-cooled radial engines, each rated at 1200 hp at 23,400 feet.
Performance:
Maximum speed 303 mph at 25,000 feet.
Cruising speed 200 mph.
Landing speed 95 mph.
Service ceiling 32,00 feet.
An altitude of 20,000 feet could be reached in 22 minutes.
Range was 2300 miles with 5000 pounds of bombs.
Range 1800 miles at maximum cruising power.
Maximum range 3500 miles.
Dimensions:
Wingspan 110 feet 0 inches
Length 66 feet 4 inches
Height 17 feet 11 inches
Wing area 1048 square feet
Weights: 32,605 pounds empty, 55,000 pounds gross
Maximum takeoff weight 64,000 pounds.
Armament: Bomb bay could accommodate up to eight 1100-pound bombs. Underwing racks for two 4000-pound bombs were available, but were seldom used. Later models could carry eight 1600-pound bombs. Defensive armanent varied signficantly according to model, as described above.
C-87
Four Pratt & Whitney R-1830-43 fourteen-cylinder air-cooled radial engines with General Electric turbosuperchargers rated at 1200 hp at 2700 rpm for takeoff.
Performance:
Maximum speed 300 mph at 25,000 feet.
An altitude of 20,000 feet could be reached in 60 minutes.
Service ceiling 28,000 feet at 56,000 pound takeoff weight.
Normal range at 60 percent power was 1400 miles at 215 mph at 10,000 feet.
Maximum range was 3300 miles at 188 mph at 10,000 feet.
Weights: 30,645 pounds empty, 56,000 pounds normal loaded.
Dimensions:
Wingspan 110 feet 0 inches
Length 66 feet 4 inches
Height 17 feet 11 inches
Wing area 1048 square feet.
Fuel: 2910 US gallons.
Accommodation: Crew was normally four (pilot, copilot, navigator, radio operator).
Up to 25 passengers could be carried.
For ranges of 1000 miles or less, average cargo capacity was 10,000 pounds. On trans-oceanic routes, cargo capacity was 6000 pounds.
The top speed is down, but only by a few mph, and the load and cruise speeds and range are very much the same. I suppose this means that the B-24D was not that bad aerodynamically.
Luckily Consolidated had done the right thing and built a model without defensive armament. It was the C-87 Liberator express.
The first C-87 was based on the B-24D, converted from a damaged bomber. The B-24D didn't have the amount of defensive armament that later models did, but it did have some. So the performance numbers surprised me a little:
B-24D
Four Pratt & Whitney R-1830-43 fourteen-cylinder turbosupercharged air-cooled radial engines, each rated at 1200 hp at 23,400 feet.
Performance:
Maximum speed 303 mph at 25,000 feet.
Cruising speed 200 mph.
Landing speed 95 mph.
Service ceiling 32,00 feet.
An altitude of 20,000 feet could be reached in 22 minutes.
Range was 2300 miles with 5000 pounds of bombs.
Range 1800 miles at maximum cruising power.
Maximum range 3500 miles.
Dimensions:
Wingspan 110 feet 0 inches
Length 66 feet 4 inches
Height 17 feet 11 inches
Wing area 1048 square feet
Weights: 32,605 pounds empty, 55,000 pounds gross
Maximum takeoff weight 64,000 pounds.
Armament: Bomb bay could accommodate up to eight 1100-pound bombs. Underwing racks for two 4000-pound bombs were available, but were seldom used. Later models could carry eight 1600-pound bombs. Defensive armanent varied signficantly according to model, as described above.
C-87
Four Pratt & Whitney R-1830-43 fourteen-cylinder air-cooled radial engines with General Electric turbosuperchargers rated at 1200 hp at 2700 rpm for takeoff.
Performance:
Maximum speed 300 mph at 25,000 feet.
An altitude of 20,000 feet could be reached in 60 minutes.
Service ceiling 28,000 feet at 56,000 pound takeoff weight.
Normal range at 60 percent power was 1400 miles at 215 mph at 10,000 feet.
Maximum range was 3300 miles at 188 mph at 10,000 feet.
Weights: 30,645 pounds empty, 56,000 pounds normal loaded.
Dimensions:
Wingspan 110 feet 0 inches
Length 66 feet 4 inches
Height 17 feet 11 inches
Wing area 1048 square feet.
Fuel: 2910 US gallons.
Accommodation: Crew was normally four (pilot, copilot, navigator, radio operator).
Up to 25 passengers could be carried.
For ranges of 1000 miles or less, average cargo capacity was 10,000 pounds. On trans-oceanic routes, cargo capacity was 6000 pounds.
The top speed is down, but only by a few mph, and the load and cruise speeds and range are very much the same. I suppose this means that the B-24D was not that bad aerodynamically.