Boeing B-17 Flying Fortress
Technical Information

Background
The Boeing B-17 Flying Fortress was designed in the late 1930s as a four engine heavy bomber. In 1934, the U.S. Army Air Corps (USAAC) tendered a proposal for a multi engine bomber to replace the Martin B-10 that could fly at an altitude of 10,000' with a useful bomb load for a duration of ten hours and a top speed of at least 200 mph.

Model 299/XB-17
Boeing designed and submitted the prototype Model 299/XB-17 designed by a team of engineers led by E. Gifford Emery and Edward Curtis Wells. On July 28, 1935 was the first flight of the Model 299 piloted by Boeing chief test pilot Leslie Tower. The new bomber was nicknamed "Flying Fortress" by The Seattle Times reporter Richard Williams and the name was adopted by Boeing and trademarked. On August 20, 1935 the Model 299 was flown from Seattle to Wright Field with a cruising speed of 252 mph. On October 30, 1935 the prototype stalled and crashed shortly after take off and burned. Despite the crash, the USAAC was impressed by the performance and ordered thirteen YB-17s for further testing and delivery to the 2nd Bombardment Group (2nd BG) at Langley Field for flight testing. A total of 155 Boeing B-17 Flying Fortress bombers were delivered to the U.S. Army Air Force (USAAF) between January 11, 1937 until November 30 1941.

The B-17 Flying Fortress in the Pacific
Prewar, B-17s were sent across the Pacific for the defense of the Philippines and assigned to the Panama Canal Zone (CZ). Early model B-17 participated in the early Pacific War, with the famous flight of B-17s that arrived December 7, 1941 during the Japanese attack. When the United States entered World War II, production quickly accelerated, and the Flying Fortress once holding the record for the highest production rate for any large plane. The 19th Bomb Group flew Flying Fortress huge distances at great odds from bases in the Philippines, Java and Australia. During the Pacific War, the B-17 developed a reputation for being rugged and earned the affection of air crews for bringing them home despite damage. B-17s also served in the Central Pacific and South Pacific (SoPAC). By the middle of 1943, B-17s in the Pacific were were replaced by the B-24 Liberator which was faster, had a longer range and could carry a larger bomb load. Regardless, a few B-17s remained in the Pacific and were converted for use as armed transports or VIP transports assigned to senior officers. Late in the Pacific War, later G models served in non-combat duties and were converted into B-17H model for air-sea rescue.

B-17B
The B-17B model first flight was June 27, 1939. Boeing model 299M sub designation. A total of 39 were built.

B-17C
The B-17C model first flight was July 21, 1940. Boeing model 299H sub designation. A total of 38 were built including twenty Model 299T for the Royal Air Force (RAF) as Fortress Mark I models with a nose .50 caliber machine gun and ferried to the United Kingdom for use in Europe.

B-17D
The B-17D model first flight was February 3, 1941. Boeing model 299H sub designation (same as B-17C). A total of 42 were built.

B-17E
During the autumn of 1940, the U.S. Army Air Force (USAAF) ordered 512 B-17E Flying Fortresses under contract W-535 ac-15677. Built by Boeing at Seattle between September 5, 1941 until May 26, 1942.

B-17F
The B-17F model first flight was May 30, 1942. A total of 3,405 were built with the Sperry ball turret.

B-17G
The B-17G model first flight was August 13, 1943. A total of 8,680 were built by Boeing, Douglas and (a subsidiary of Lockheed Aircraft Company) with a nose chin turret and staggered waist gunner positions.

B-17H
The B-17H model were converted for the air-sea rescue role with a Higgins A-1 lifeboat attached to the lower fuselage. A total of 130 B-17G were converted into the B-17H variant.

XC-108 / C-108
Transport variant of the B-17 Flying Fortress. Four B-17s were converted into transports with all armament removed except nose and tail guns. The fuselage interior was modified with windows, cooking facilities and living space with a drop-down door with steps installed in the rear fuselage instead of the standard door. The first conversion was B-17E 41-2593 / XC-108 "Bataan" for General Douglas MacArthur.

Production
A total of 12,731 B-17s were been built by Boeing, Douglas, and Vega between July 28, 1935 until May 1945 when production ceased.

Technical Details
Crew  10 (pilot, co-pilot, navigator, bombardier, radio, engineer, ball gunner, left waist gunner, right waist gunner, tail gunner)
Engine  4 x Wright R-1820 cyclone radial engine driving a three bladed propeller
Span  103' 10"
Length  74' 4"
Height  19' 1"
Cruise Speed  170 mph
Range  1,850 miles
Armament  10–12 x .50 caliber M2 machine guns
Bomb Load  6,400 lbs