Battle Stations III
Boeing
B-17 Flying Fortress
Wing
span 31.62m (103.75ft)
Engines 4 x 1,200hp Wright Cyclone R-1820-97 radials
Armament 13 x 0.5in machine guns, 1 x 0.3in machine
gun
Bomb load Normal 2,724kg (6,000lb), maximum 5,800kg
(12,800lb)
Maximum speed 287mph
Service ceiling 10,670m (35,000ft)
Range 1,100 miles with maximum bomb load
Crew Up to 10
Evolution
The B-17 evolved from a 1934 US Army Air Force (USAAF) requirement for an experimental long-range bomber. The four-engined prototype, massive for its day but with a streamlined profile and provision for heavy defensive armament, made its first appearance in July 1935 and was dubbed the 'Flying Fortress'.
The USAAF ordered 13 pre-production models, designated Y1B-17, for evaluation trials and, in 1938, placed a production contract for 39 B-17B aircraft, the last of which was delivered in March 1940. All were equipped with the sophisticated Norden tachometric bombsight capable, its designers claimed, of dropping a bomb 'in a pickle barrel from 25,000 feet'.
A modern wonder in the crystal-clear air over the USAAF's Nevada testing grounds, the aircraft was to prove more problematic in the cloudy, flak-filled skies of wartime Europe.
A strategic bombing campaign
After the outbreak of war in Europe, the Royal Air Force took delivery of 20 B-17Cs to fly high-altitude sorties over northern Europe and North Africa. These were subsequently transferred to RAF Coastal Command with which they performed sterling work as maritime patrol aircraft.
After the United States entered the war in December 1941, the US 8th Air Force began the long task of preparing to mount a strategic bombing campaign against Nazi Germany from airfields in England. It launched its first raid on occupied Europe on 17 August 1942 when 12 B-17Fs of 97th Bombardment Group attacked rail yards at Rouen.
Heavy losses
The USAAF was confident that tight, self-defending formations of B-17s, flying fast and at high altitude, could penetrate enemy air space by day without fighter escort. After all, a combat wing of 54 aircraft, each carrying 9,000 rounds of ammunition, could bring to bear 648 0.5in-machine guns firing 14 rounds a second over an effective range of 600 yards.
However, once 8th Air Force began to make deeper penetrations into Germany itself from the spring of 1943, it sustained increasingly heavy losses at the hands of German fighters. By the autumn of 1943, German fighters, alerted by radar and deployed in depth, were destroying 8th Air Force's bombers and crews more quickly than they could be replaced.
Hurricane force
By now the B-17E had been followed by the more heavily armed B-17F, the first of which had left the production line in May 1942. Over the next 15 months, 3,405 B-17Fs were delivered, boasting some 400 technical modifications, among them more powerful engines, improved oxygen systems for the crew (flying and fighting in a B-17 was an immensely gruelling task) and better radio communications.
The B-17G, which appeared in numbers in the autumn of 1943, was equipped with a chin turret and glazed waist windows, a measure that eliminated the near hurricane-force winds that could lash the inside of the B-17's fuselage.
Turning the tide
The introduction, in the spring of 1944, of the P-51D escort fighter, capable of accompanying the bomber formations to targets deep within Germany, turned the tide in the ferocious battles for air supremacy over the Reich. By August 1944, 4,574 B-17s were in front-line service in 33 bomber groups, and the aircraft remained the backbone of the USAAF's strategic effort in Europe for the remainder of the war.
A total of 12,731 B-17s were produced between 1935 and 1945. Some 4,750 of them were lost on combat missions. The last B-17 delivery was made in April 1945.
