Boeing B-17E Fortress

Last revised December 11, 2001




The B-17E was the first version of the Fortress to be produced in large numbers. It was originally designed to correct some of the deficiencies in the earlier Fortresses that had been brought to light as a result of combat reports coming in from Europe. The modifications which resulted in the B-17E were destined to turn an airplane which had been a relative failure into an outstanding success.

It is often written that the B-17E was the result of initial experience with the B-17C and D during the first months of combat in 1942 in the Pacific against the Japanese. Other sources report that the B-17E had its origin in the negative experience that the RAF had with the Fortress I (B-17C) over Europe in the summer of 1941. Neither view is correct, since the B-17E was first ordered on August 30, 1940, and the first prototype took to the air on its maiden flight on September 5, 1941.

The crews of early Fortresses (primarily B-17C and D) were well aware of the existence of a rather severe blind spot immediately to the rear, making it almost impossible to direct defensive firepower against an enemy fighter approaching from that direction. Early USAAC Fortress pilots had been forced to devise some rather ingenious maneuvering techniques to get around this problem--when attacked from the rear they would jink the aircraft back and forth, making it possible for the left and then the right waist gunners alternatively to get in fleeting shots at the attacker. However, in the tight formations that became de rigeur during missions over Germany during 1943-44, such maneuvering would have been downright dangerous.

In search of a better solution, the B-17E introduced a completely new rear fuselage with a manually-operated turret housing two 0.50-inch machine guns fitted in the extreme tail. In order to accommodate the tail gun, the fuselage of the B-17E was a full six feet longer than that of the D.

A Bendix electrically-powered turret containing two 0.50-inch machine guns was installed on the upper fuselage immediately behind the flight deck. This turret was usually operated by the flight engineer. The oval waist positions were replaced by rectangular apertures with removable windows. A single 0.50-inch machine gun could be mounted behind each of these windows.

A power-operated belly turret replaced the ventral "bathtub" housing of the B-17D. This turret was remotely-controlled by a system of mirror periscopic sights from a Plexiglas bubble below the waist hatches.

In order to achieve better stability during the bomb run, the span of the horizontal tailplane was increased, the vertical tail was greatly increased in area, and a long dorsal fin was fitted in front of the tail.

The first B-17E flew on September 5, 1941. It immediately superseded the B-17D on the production line, and as fast as they could leave the production line, they were issued to operational units.

The demands of American rearmament were such that far many more B-17s were required than which Boeing alone could supply, and the Army Air Forces encouraged the organization of a manufacturing pool in which Boeing, the Vega division of Lockheed, and Douglas would all participate in the building of the B-17E. The pool became rather irreverently known as "B.V.D", after the trade name for a popular line of underwear which had become a household name in America. Production of the B-17E at the main Boeing plant at Seattle was to be augmented by another Boeing plant at Wichita, Kansas. The Douglas plant at Santa Monica, California was to be joined in B-17E production by a new Douglas plant at Long Beach, California which had been built specifically for Fortress production. However, before the plan could reach fruition, the B-17F was ready for production, and the F was the first version to built jointly by all three companies. No B-17Es were actually built by either Lockheed or Douglas

The B-17E was first delivered to combat units of the 7th Bombardment Group in November of 1941. By November 30, 1941, 42 B-17Es had been delivered. Some B-17Es were actually at Pearl Harbor during the attack.

The increased weight and drag of the protruding turrets made the B-17E somewhat slower than the previous B-17D, although its ability to defend itself was greatly improved.

The periscope sight for the remotely-controlled dorsal turret proved difficult to use in practice, and starting with the 113th B-17E, the remotely-controlled turret was replaced by a Sperry ball turret, inside of which a gunner sat all curled up in the foetal position, swiveling the entire turret as he aimed the two guns. With his left eye peering through a sight, he controlled the movement of the guns by hand and foot pedals. There was precious little space inside the turret--ball turret gunners had to be very small men.

The gunner entered the ball turret via a door at its rear, which also served as an emergency exit in case of trouble. The gunner could enter the turret from inside the plane by having the turret rotated until the door opening faced the interior of the plane. However, since this required that the ball turret be positioned so that the guns were pointed downward, this meant that the turret could not be entered from inside the plane while it was on the ground. It was possible for the gunner to enter the turret from outside the plane while it was on the ground by having it rotated so that its door faced outside the plane. However, once he did this, he would have to stay inside the turret during the takeoff. Since the turret was only 15 inches off the ground, it would take a bold soul to ride inside the belly turret during take off or landing, and most ball turret gunners chose to enter the turret while the plane was in the air.

The B-17E normally carried a crew of ten--pilot, copilot, bombardier, navigator, flight engineer, radio operator, tail gunner, belly gunner, and two waist gunners. The nose gun was operated by either the navigator or the bombardier when they were not occupied by their primary duties, and the dorsal turret was normally operated by the flight engineer.

The temperature in the tail section when the side ports were open was quite frigid at high altitudes, especially in the wintertime. Plug-in points for electrically- heated flight suits were a must. Perhaps the coldest spot of all was the tail gunner's position, since a hurricane of drafts always seemed to converge on this spot.

The B-17E could be entered from three separate doors--a nose hatch located on the lower left, the main door located just in front of the right horizontal stabilizer, and the tail gunner's escape hatch situated just underneath the right elevator. Many movies depict the crew entering the Fortress via the nose hatch by swinging themselves upward into the plane. However, this mode of entrance was generally only for show, and was most often used only in Hollywood movies such as Twelve O'clock High. Since aircrew were almost always heavily encumbered with flight suits and parachutes, they generally opted for a less dramatic but less athletically-demanding entrance via the main door in the rear.

The last B-17E rolled off the production line at Boeing on May 28, 1942. A total of 512 were built before it was immediately superseded on the production line by the B-17F.

Very few B-17Es survive today. One of them is 41-2595, which had been converted in 1944 to a transport under the designation XC-108A. After the war, this plane was consigned to a junkyard where it sat forlornly in pieces for many years. In 1985, the bits and pieces of 41-2595 were recovered by an aviation antique enthusiast and moved to Galt Airport in Illinois, where they await reassembly and restoration. Another B-17E is 41-2446, which had been abandoned in Papua New Guinea in February of 1942 after crash-landing into a marsh. It was actually not badly damaged, and several American groups have begun attempts to extract the aircraft and return it to the USA for restoration and display. B-17Es 41-9101 and 41-9105 suffered a different fate-they were escorting a flight of six P-38Fs across the Atlantic to England in July of 1942 when they encountered bad weather and all aircraft were forced to land in a remote area of Greenland. The crewmen were all rescued, but the planes had to be abandoned. They were relocated underneath 260 feet of snow in 1987, and attempts were made to bring them to the surface for possible restoration. B-17E 41-9210 had been used as a testbed during the war. After the war, it was sold off as surplus on the commercial market. It went through a succession of users in both the USA and Canada, and eventually ended up with a Bolivian airline and was assigned to freight runs. It was damaged in a takeoff accident in 1976, and became a spare parts source for other B-17s serving with the airline. It sat derelict at La Paz until 1990 when recovered by Don Whittington of World Jet of Fort Lauderdale, FL. It was returned to USA under the civil registration N8WJ. It was flown in September of 1998 to Moses Lake, WA and was transferred to the Flying Heritage Museum of Bellevue, WA, where it is currently under restoration.

If you want information about the fates of some individual B-17Es, check out my serial number page.

Serials of Boeing B-17E Fortress:

41-2393/2669		Boeing B-17E Fortress
				c/n 2204/2480
				2401 converted to XB-38-VE with Allison V-1710
				 liquid-cooled engines.
41-9011/9245		Boeing B-17E Fortress
				c/n 2483/2717

Specification of Boeing B-17E Fortress:

Four Wright R-1820-65 Cyclone radials rated at 1200 hp for takeoff and 1000 hp at 25,000 feet. Performance: Maximum speed 318 mph at 25,000 feet. cruising speed 195-223 mph. Landing speed 70 mph Service ceiling 36,600 feet. Normal range 2000 miles with 4000 pounds of bombs. Maximum range 3300 miles. Initial climb rate 1430 feet per minute. An altitude of 5000 feet could be attained in 7 minutes. Dimensions: wingspan 103 feet 9 3/8 inches, length 73 feet 10 inches, height 19 feet 2 inches, wing area 1420 square feet. Weights: 32,350 pounds empty, 40,260 pounds gross, 53,000 pounds maximum. Fuel: Normal fuel load was 2490 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: one 0.30-inch machine gun which could be mounted on any one of six ball-and-socket mounts in the extreme nose. One Sperry No. 645473E power turret in the dorsal position with two 0.50 Browning M2 machine guns with 500 rounds per gun. One Sperry No. 654849-J power turret in ventral position with two 0.50-inch Browning machine guns with 500 rounds per gun. One 0.50-inch Browning M2 machine gun is each of the two waist windows, 400 rounds per gun. Two 0.50-inch M2 Browning machine guns in the tail position, with 500 rounds per gun. Maximum bomb load was 26 100-pound bombs, or 16 300-pound bombs, or 12 500-pound bombs, or 8 1000-pound bombs, or 4 2000-pound bombs.

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 Postwar B-17 Flying Fortress: The Survivors, Scott A. Thompson, Pictorial Histories Publishing Corp, 1993.