Boeing B-17G Fortress

Last revised January 14, 2020



The B-17G was introduced onto the Fortress production line in July of 1943, and was destined to be produced in larger numbers than any other Fortress variant. The most readily-noticeable innovation introduced by the B-17G was the power-operated Bendix turret mounted in a chin-type installation underneath the nose. This turret was equipped with two 0.50-inch machine guns. This installation had first been tested in combat by the YB-40 and was found to be the only viable innovation introduced by the unsuccessful escort Fortress. Originally, the Bendix turret was to be introduced on the Boeing production line with F-135, but the changes were sufficient to justify a new series letter, and the F-135s became G-1. However, the Bendix chin turret was actually first used on some late-model B-17Fs.

Another feature introduced by the G was having the waist guns being permanently enclosed behind windows instead of being mounted behind removeable hatches. This made the rear fuselage somewhat less drafty.

The cheek nose guns introduced on the late B-17F were retained, but were staggered so that the left gun was in the forward side window and the right gun was in the middle side window, which reversed the positions used on the late Fs. The cheek gun mounts bulged somewhat outward into the airstream, which helped to improve the forward view from the cheek gun positions. The forward chin installation and the associated cheek guns were first tested out on B-17F-115-BO 42-30631.

The B-17G now had the defensive firepower of no less than thirteen 0.50-inch machine guns--two chin guns, two "cheek" guns, two guns in the dorsal turret, two guns in the ventral turret, two guns in the waist, two guns in the tail, and one gun in the roof of the radio operator's position.

B-17Gs were built by all three members of the "BVD" production pool, with the Boeing lots ranging from production blocks G-1 to G-110, the Douglas blocks ranging from 5 to 95, and the Lockheed-Vega blocks ranging from 1 to 110.

The B-17G entered service with the Eighth and Fifteenth Air Forces in late 1943.

Camouflage paint was deleted from production B-17Gs starting in January of 1944. B-17Gs were delivered in natural metal finish starting in (but not at the beginning) of production blocks G-35-BO (Boeing), G-20-VE (Lockheed-Vega), and G-35-DL (Douglas-Long Beach).

The so-called "Cheyenne" tail gun mounting modifications were incorporated in the B-17G-80-BO, -45-DL, -55-VE and subsequent batches. These tail gun mountings also had a reflector gunsight instead of the previous ring and bead. With this installation, these B-17Gs were five inches shorter than the earlier versions.

On later production versions, it was found necessary to stagger the waist gun positions so that the two gunners would not get in each other's way.

On the last production batches (B-17G-105 and -110-BO, B-17G-75 to -85-DL, and B-17G-85 to -110-VE), the raddio compartment gun was not installed. The ammunition capacity of the waist guns was increased to 600 rpg.

When production finally terminated in 1945, a total of 4035 B-17Gs had been built by Boeing, 2395 by Douglas, and 2250 by Lockheed-Vega. The last Boeing-built B-17G was delivered on April 13, 1945.

B-17G-1-VE 42-39840 was redesignated XB-17G when assigned to test work. It was not a prototype.

If you want to know the fates of some individual B-17Gs, check out my serial number page.

B-17G serial numbers:

42-31032/31131	Boeing B-17G-1-BO Fortress
				c/n 6146/6245
42-31132/31231	Boeing B-17G-5-BO Fortress
				c/n 6246/6345
42-31232/31331	Boeing B-17G-10-BO Fortress
				c/n 6346/6445
42-31332/31431	Boeing B-17G-15-BO Fortress
				c/n 6446/6545
42-31432/31631	Boeing B-17G-20-BO Fortress
				c/n 6546/6745
42-31632/31731	Boeing B-17G-25-BO Fortress
				c/n 6746/6845
42-31732/31931	Boeing B-17G-30-BO Fortress
				c/n 6846/7045
42-31932/32116	Boeing B-17G-35-BO Fortress
				c/n 7046/7230
42-37716		Douglas-Long Beach B-17G-10-DL Fortress
				c/n 8502
42-37721/37803	Douglas-Long Beach B-17G-10-DL Fortress
				c/n 8507/8589
42-37804/37893	Douglas-Long Beach B-17G-15-DL Fortress
				c/n 8590/8679
42-37894/37988	Douglas-Long Beach B-17G-20-DL Fortress
				c/n 8680/8774
42-37989/38083	Douglas-Long Beach B-17G-25-DL Fortress
				c/n 8775/8869
42-38084/38213	Douglas-Long Beach B-17G-30-DL Fortress
				c/n 8870/8999
42-39758/39857  	Lockheed/Vega B-17G-1-VE Fortress
				c/n 6501/6600
42-39858/39957  	Lockheed/Vega B-17G-5-VE Fortress
				c/n 6601/6700
42-39958/40057  	Lockheed/Vega B-17G-10-VE Fortress
				c/n 6701/6800
				39974 captured by Luftwaffe
42-97058/97172	Boeing B-17G-40-BO Fortress
				c/n 7531/7645
42-97173/97407	Boeing B-17G-45-BO Fortress
				c/n 7646/7880
42-97436/97535	Lockheed/Vega B-17G-15-VE Fortress
				c/n 6801/6900
42-97536/97635	Lockheed/Vega B-17G-20-VE Fortress
				c/n 6901/7000
42-97636/97735	Lockheed/Vega B-17G-25-VE Fortress
				c/n 7001/7100
42-97736/97835	Lockheed/Vega B-17G-30-VE Fortress
				c/n 7101/7200
				97825 converted to SB-17G.
42-97836/97935	Lockheed/Vega B-17G-35-VE Fortress
				c/n 7201/7300
42-97936/98035	Lockheed/Vega B-17G-40-VE Fortress
				c/n 7301/7400
42-102379/102543	Boeing B-17G-50-BO Fortress
				c/n 7881/8045
42-102544/102743	Boeing B-17G-55-BO Fortress
				c/n 8046/8245
42-102744/102978	Boeing B-17G-60-BO Fortress
				c/n 8246/8480
42-106984/107233	Douglas-Long Beach B-17G-35-DL Fortress
				c/n 21899/22148
43-37509/37673	Boeing B-17G-65-BO Fortress
				c/n 8487/8651
43-37674/37873	Boeing B-17G-70-BO Fortress
				c/n 8652/8851
43-37874/38073	Boeing B-17G-75-BO Fortress
				c/n 8852/9051
43-38074/38273	Boeing B-17G-80-BO Fortress
				c/n 9052/9251
43-38274/38473	Boeing B-17G-85-BO Fortress
				c/n 9252/9451
43-38474/38673	Boeing B-17G-90-BO Fortress
				c/n 9452/9651
43-38674/38873	Boeing B-17G-95-BO Fortress
				c/n 9652/9851
43-38874/39073	Boeing B-17G-100-BO Fortress
				c/n 9852/10051
43-39074/39273	Boeing B-17G-105-BO Fortress
				c/n 10052/10251
43-39274/39508	Boeing B-17G-110-BO Fortress
				c/n 10252/10486
44-6001/6125		Douglas/Long Beach B-17G-40-DL Fortress
				c/n 22224/22348
44-6126/6250		Douglas/Long Beach B-17G-45-DL Fortress
				c/n 22349/22473
44-6251/6500		Douglas/Long Beach B-17G-50-DL Fortress
				c/n 22474/22723
44-6501/6625		Douglas/Long Beach B-17G-55-DL Fortress
				c/n 22724/22848
44-6626/6750		Douglas/Long Beach B-17G-60-DL Fortress
				c/n 22849/22973
44-6751/6875		Douglas/Long Beach B-17G-65-DL Fortress
				c/n 22974/23098
44-6876/7000		Douglas/Long Beach B-17G-70-DL Fortress
				c/n 23099/23223
44-8001/8100		Lockheed/Vega B-17G-45-VE Fortress
				c/n 7401/7500
44-8101/8200		Lockheed/Vega B-17G-50-VE Fortress
				c/n 7501/7600
44-8201/8300		Lockheed/Vega B-17G-55-VE Fortress
				c/n 7601/7700
44-8301/8400		Lockheed/Vega B-17G-60-VE Fortress
				c/n 7701/7800
44-8401/8500		Lockheed/Vega B-17G-65-VE Fortress
				c/n 7801/7900
44-8501/8600		Lockheed/Vega B-17G-70-VE Fortress
				c/n 7901/8000
44-8601/8700		Lockheed/Vega B-17G-75-VE Fortress
				c/n 8001/8100
44-8701/8800		Lockheed/Vega B-17G-80-VE Fortress
				c/n 8101/8200
44-8801/8900		Lockheed/Vega B-17G-85-VE Fortress
				c/n 8201/8300
44-8901/9000		Lockheed/Vega B-17G-90-VE Fortress
				c/n 8301/8400
44-83236/83360	Douglas/Long Beach B-17G-75-DL Fortress
				c/n 31877/32001
44-83361/83485	Douglas/Long Beach B-17G-80-DL Fortress
				c/n 32002/32126
44-83486/83585	Douglas/Long Beach B-17G-85-DL Fortress
				c/n 32127/32226
44-83586/83685	Douglas/Long Beach B-17G-90-DL Fortress
				c/n 32227/32326
44-83686/83863	Douglas/Long Beach B-17G-95-DL Fortress
				c/n 32327/32504
44-83864/83885	Douglas/Long Beach B-17G-95-DL Fortress
				c/n 32505/32526
44-85492/85591	Lockheed/Vega B-17G-95-VE Fortress
				c/n 8401/8500
44-85592/85691	Lockheed/Vega B-17G-100-VE Fortress
				c/n 8501/8600
44-85692/85791	Lockheed/Vega B-17G-105-VE Fortress
				c/n 8601/8700
44-85792/85841	Lockheed/Vega B-17G-110-VE Fortress
				c/n 8701/8750

Specification of B-17G:

Engines: Four Wright R-1820-97 Cyclone radials with General Electric B-22 turbosuperchargers, each rated at 1200 hp for takeoff and 1000 hp at 25,000 feet, with a war emergency power of 1380 hp at 26,700 feet. Performance: Maximum speed 263 mph at 25,000 feet, 300 mph at 30,000 feet (war emergency). Cruising speed 150 mph at 25,000 feet. Landing speed 90 mph Initial climb rate 900 feet per minute. An altitude of 20,000 feet could be attained in 37 minutes. Service ceiling 35,000 feet. Range 1850 miles with 4000 pounds of bombs at 25,000 feet with 2810 gallons of fuel. Dimensions: Wingspan 103 feet 9 3/8 inches, length 74 feet 9 inches, height 19 feet 1 inches, wing area 1420 square feet. Weights: 32,720 pounds empty, 55,000 pounds normal loaded, 72,000 pounds maximum. Fuel: Normal fuel load was 2520 US gallons, but extra fuel tanks could be installed which raised total fuel capacity to 3612 US gallons. Armament: Specified defensive armament was as follows: Thirteen 0.5-inch Browning machine guns in chin, nose, dorsal, center- fuselage, ventral, waist, and tail positions. Maximum short-range bombload was 17,600 pounds.

Sources:



  1. Flying Fortress, Edward Jablonski, Doubleday, 1965.

  2. Famous Bombers of the Second World War, Volume One, William Green, Doubleday, 1959.

  3. Boeing Aircraft Since 1916, Peter M. Bowers, Naval Institute Press, 1989.

  4. United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.

  5. Lockheed Aircraft Since 1913, Rene J. Francillon, Naval Institute Press, 1987.

  6. Boeing B-17E and F Flying Fortress, Charles D. Thompson, Profile Publications, 1966.

  7. American Combat Planes, Ray Wagner, Third Edition, Doubleday, 1982.

  8. Jane's Fighting Aircraft of World War II, Military Press, 1989.

  9. Final Cut: The Post-War B-17 Flying Fortress: The Survivors, Scott A. Thompson, Pictorial Histories Publishing Co., 1990.

  10. E-mail from Ewo van Houten on 42-38940 being XB-17G.

  11. E-mail from Phil Marchese on Vega tail gun changeover being block G-55-VE is the correct point