Boeing B-17B Flying Fortress

Boeing B-17B Flying Fortress (BS 34) at March Field, Riverside, California, 1940.

The B-17B (299M) was the first production model of the B-17 and was essentially a B-17A with a larger rudder, larger flaps, and a redesigned nose and 1,200 hp (895 kW) R-1820-51 engines. The small, globe-like, machine gun turret used in the Y1B-17's upper nose blister was replaced with a .30 caliber (7.62 mm) machine gun, its barrel run through a ball-socket in the ten-panel Perspex nose glazing. This was held in place by both the socket's strength combined with a flexible interior support strap, which later became an aluminum-reinforced window pane. The Y1B-17's separate triangular-shaped bombardier's aiming window, located further back in the lower nose, was eliminated, replaced with a framed window panel in the lower portion of the nose glazing; this configuration was used on all Flying Fortress airframes up through the B-17E series. All B-17B aircraft were later modified at Boeing, being brought up to the B-17C/D production standard. While the new nose glazing still used only a single .30 caliber machine gun, two additional ball-sockets were installed in the nose, one in the upper left panel and another in a lower right. This three ball-socket layout was continued up through the B-17E series. During Army Air Corps service, the bulged teardrop-shaped machine gun blisters were replaced with flush-mounted Perspex side windows of the same type used in the B-17C/D series. Various aircraft had different levels of upgrades performed. Some of the "B" series Fortresses had only their bulged side blisters replaced with slide-out flush windows, while others also had their bulged upper blister changed to a much flatter, more aerodynamic Perspex window panel. In addition, some "B" series Fortresses also had ventral "bathtub turrets" (see the "C/D" section below) installed, replacing their lower, teardrop-shaped gun blisters.

Crew locations were rearranged, and the original pneumatic brake system was replaced with more efficient hydraulic brakes.

In October 1942 all in-service B-17B aircraft were redesignated RB-17B, the "R" indicating "Restricted". These aircraft were now used only for training, transport, messenger, and liaison duties. The "R" prefix became a designation for combat obsolescence.

Many of these RB-17B aircraft, along with at least one still-airworthy YB-17, were stationed at Sebring Airfield, where the exterior scenes were filmed for the Warner Bros. war drama Air Force (1943), directed by Howard Hawks, and starring (among others) John Garfield, Arthur Kennedy, Gig Young, and Harry Carey. The film's real star, however, was an RB-17B (United States Army serial number 38-584), carrying on its upper rudder the "security-conscious" false serial number "05564". It passed as a later model B-17D Flying Fortress, having had its machine gun blisters replaced and a lower "bathtub" ventral gun turret installed. Many of these aircraft can still be seen in both ground and aerial scenes during the film.

The "B" series Flying Fortress made its maiden flight on 27 June 1939. 39 were built in a single production run, but Army Air Corps serial numbers were scattered over several batches. This was because of limited government funding: The Army Air Corps could only afford to purchase a few B-17Bs at a time.

Boeing B-17B just after takeoff; circa 1930.

Boeing B-17Bs at March Field, California, 1941, prior to Pearl Harbor.

B-17B Flying Fortress 38-270, Hendricks Army Airfield, Florida, 1942.

B-17B Flying Fortress; circa 1940.

Boeing B-17B.

Boeing B-17B, July 27, 1939.

B-17B.

B-17B.

B-17Bs.

Twelve U.S. Army Air Forces Boeing B-17B Flying Fortresses in flight; circa 1939.

Boeing B-17B at Esler Airfield, Louisiana. Aircraft was assigned to Ladd Field, Alaska; 11 June 1941.

Boeing B-17B; circa 1940.

Boeing B-17B.

The B-17B Flying Fortress set an official non-stop coast-to-coast record for airplanes in 1937 by flying from California to New York in 9 hours, 14.5 minutes.

B-17B, natural metal finish, on a test flight near Seattle.

Only 39 B-17Bs were built, They were very similar in external appearance to the Y1B-17, the main changes being turbo-supercharged Wright Cyclone engines as standard, giving a significant performance increment, a larger, re-designed rudder for greater lateral stability at high altitudes, and a revised transparent nose with an optically flat panel in front of the bombsight. Many other changes took place under the skin. It was a step in the right direction.

Twenty-nine officers and 28 enlisted men of the U.S. Army Air Corps took off from Langley Field, Virginia, 10 November 1939, on a Friendship Flight to South America.

Boeing B-17B Flying Fortress.

Three American air force personnel with a B-17B.

A rare color slide taken inside a B-17B showing the port waist gun position. On the early Fortresses the gun positions were in bulged “teardrop” blisters, the guns pivoted and rotated within. On all Fortresses the after fuselage interior was specified to remain in natural aluminum.

Boeing B-17B (40-3092) photographed in 1944 still wearing olive drab and medium green camouflage. The yellow designator is painted on the rudder, preferred position for these early Fortresses.

Boeing B-17B.

Boeing B-17B, Grand Central Air Terminal.