16 July 1935: Just over a year after design began, the Boeing Model 299, NX13372, a prototype four engine long range heavy bomber, was rolled out of its hangar at Boeing Field, Seattle, Washington for the first time. The largest land airplane built up to that time, it seemed to have defensive machine guns aimed in every direction. A Seattle Times reporter, Roland Smith, wrote that it was a “flying fortress.” Boeing quickly copyrighted the name.
After several years of testing, the Model 299 went into production as the B-17 Flying Fortress. By the end of World War II, 12,731 B-17 Flying Fortresses had been built by Boeing, Douglas and Lockheed Vega.
The Boeing Model 299 was a four-engine bomber operated by a crew of eight. It was designed to meet a U.S. Army Air Corps proposal for a multi-engine bomber that could carry a 2,000 pound (907 kilogram) bomb load a distance of 2,000 miles (3,219 kilometers) at a speed greater than 200 miles per hour (322 kilometers per hour). Design of the prototype began in June 1934 and construction was started 16 August 1934. The Air Corps designated it B-299, and later, XB-17. It did not carry a military serial number, being marked with civil registration NX13372.
The Model 299 was 68 feet, 9 inches (20.955 meters) long with a wingspan of 103 feet, 9–3/8 inches (31.633 meters) and height of 14 feet, 11–5/16 inches (4.554 meters). Its empty weight was 21,657 pounds (9,823 kilograms). The maximum gross weight was 38,053 pounds (17,261 kilograms).
The prototype was powered by four air-cooled, supercharged, 1,690.537-cubic-inch-displacement (27.703 liter) Pratt & Whitney Hornet S1E-G nine-cylinder radial engines with a compression ratio of 6.5:1. The S1E-G was rated at 750 horsepower at 2,250 r.p.m., and 875 horsepower at 2,300 r.p.m. for takeoff, using 87-octane gasoline. They turned 11 foot, 6 inch (3.505 meters) diameter, three-bladed Hamilton Standard Hydromatic constant-speed propellers through a 3:2 gear reduction. The S1E-G was 4 feet, 1.38 inches (1.254 meters) long, 4 feet, 6.44 inches (1.383 meters) in diameter and weighed 1,064 pounds (483 kilograms)
In flight testing, the Model 299 had a cruise speed of 204 miles per hour (328 kilometers per hour) and a maximum speed of 236 miles per hour (380 kilometers per hour) at 10,000 feet (3,048 meters). The service ceiling was 24,620 feet (7,504.2 meters). The maximum range was 3,101 miles (4,991 kilometers). Carrying a 2,573 pounds (1,167 kilograms) load of bombs, the range was 2,040 miles (3,283 kilometers).
The XB-17 could carry eight 500 pound (227 kilogram) bombs in an internal bomb bay. Defensive armament consisted of five air-cooled .30-caliber Browning machine guns.
NX13372 was destroyed when it crashed on takeoff at Wright Field, Dayton, Ohio, 30 October 1935. An Army Air Corps pilot making his first familiarization flight neglected to remove the control locks. This incident led directly to the creation of the “check list” which today is used by all aircraft crew members.
30 May 1942: The Boeing B-17F Flying Fortress makes its first flight. B-17F-1-BO 41-24340 was the first of a new series of the famous World War II bomber. While visually similar to the B-17E, it had more than 400 improvements based on early wartime experience with the B-17D and B-17E.
The Boeing B-17F Flying Fortress was a four-engine heavy bomber operated by a flight crew of ten. It was 74 feet, 8.90 inches (22.781 meters) long with a wingspan of 103 feet, 9.375 inches (31.633 meters) and an overall height of 19 feet, 1.00 inch (5.187 meters). The wings have 3½° angle of incidence and 4½° dihedral. The leading edge is swept aft 8¾°. The total wing area is 1,426 square feet (132.48 square meters). The horizontal stabilizer has a span of 43 feet (13.106 meters) with 0° incidence and dihedral. Its total area, including elevators, is 331.1 square feet (12.18 square meters).
The B-17F had an approximate empty weight of 36,135 pounds (16,391 kilograms), 40,437 pounds (18,342 kilograms) basic, and the maximum takeoff weight was 65,000 pounds (29,484 kilograms).
The B-17F was powered by four air-cooled, supercharged, 1,823.129-cubic-inch-displacement (29.876 liters) Wright Cyclone C9GC (R-1820-97) nine-cylinder radial engines with a compression ratio of 6.70:1. (Early production B-17Fs were equipped with the Wright Cyclone G666A (R-1820-65). Both variants had the same power ratings.) The engines were equipped with remote General Electric B-22 turbochargers capable of 24,000 r.p.m. The R-1820-97 was rated at 1,000 horsepower at 2,300 r.p.m. at Sea Level, and 1,200 horsepower at 2,500 r.p.m. for takeoff. The engine could produce 1,380 horsepower at War Emergency Power. 100-octane aviation gasoline was required. The Cyclones turned three-bladed, constant-speed, Hamilton-Standard Hydromatic propellers with a diameter of 11 feet, 7 inches (3.835 meters) through a 0.5625:1 gear reduction. The R-1820-97 engine is 47.80 inches (1.214 meters) long and 55.10 inches (1.399 meters) in diameter. It weighs 1,315 pounds (596 kilograms).
The B-17F had a cruising speed of 200 miles per hour (322 kilometers per hour). The maximum speed was 299 miles per hour (481 kilometers per hour) at 25,000 feet (7,620 meters), though with War Emergency Power, the bomber could reach 325 miles per hour (523 kilometers per hour) at 25,000 feet for short periods. The service ceiling was 37,500 feet (11,430 meters).
With a normal fuel load of 1,725 gallons (6,530 liters) the B-17F had a maximum range of 3,070 miles (4,941 kilometers). Two “Tokyo tanks” could be installed in the bomb bay, increasing capacity by 820 gallons (3,104 liters). Carrying a 6,000 pound (2,722 kilogram) bomb load, the range was 1,300 miles (2,092 kilometers).
The B-17F Flying Fortress was armed with up to 13 air-cooled Browning AN-M2 .50-caliber machine guns. Power turrets mounting two guns each were located at the dorsal and ventral positions. A pair of machine guns were mounted in the tail, and single guns on flexible mounts were placed in the nose, radio compartment, and right and left waist positions.
The maximum bomb load of the B-17F was 20,800 pounds (9434.7 kilograms) over very short ranges. Normally, 4,000–6,000 pounds (1,815–2,722 kilograms) of high explosive bombs were carried. The internal bomb bay could be loaded with a maximum of eight 1,600 pound (725.75 kilogram) bombs. Two external bomb racks mounted under the wings between the fuselage and the inboard engines could carry one 4,000 pound (1,814.4 kilogram) bomb, each, though this option was rarely used.
The B-17 Flying Fortress first flew in 1935, and was in production from 1937 to 1945. 12,731 B-17s were built by Boeing, Douglas Aircraft Company and Lockheed-Vega. (The Manufacturer Codes, -BO, -DL and -VE, follow the Block Number in each airplane’s type designation.) 3,405 of the total were B-17Fs, with 2,000 built by Boeing, 605 by Douglas and 500 by Lockheed-Vega.
Only three B-17F Flying Fortresses remain in existence.
15 April 1952: At 11:09 a.m., Boeing’s Chief of Flight Test, Alvin M. “Tex” Johnston, and Lieutenant Colonel Guy M. Townsend, U.S. Air Force, ran all eight turbojet engines to full power and released the brakes on the YB-52 Stratofortress prototype, 49-231.
With an awesome eight-engine roar, the YB-52 sprang forward, accelerating rapidly, wings curving upward as they accepted the 235,000-pound initial flight gross weight. At V2 (takeoff speed) the airplane lifted off the runway, because of the 6-degree angle of incidence of the wing, and at 11:08 a.m. we were airborne. The initial flight of the YB-52 had begun.
—Tex Johnston: Jet-Age Test Pilot, by A.M. “Tex” Johnston with Charles Barton, Smithsonian Books, Washington, D.C., 1992, Chapter 13 at Pages 397–398.
The YB-52 remained over the Seattle area for approximately 40 minutes while Johnson and Townsend ran through a series of systems checks. When completed, they climbed to 25,000 feet (7,620 meters) and flew the new bomber to Larson Air Force Base at Moses Lake, Washington, where they stayed airborne for continued testing. The Stratofortress finally touched down after 3 hours, 8 minutes—the longest first flight in Boeing’s history up to that time. Johnston radioed that the airplane performed exactly as the engineers had predicted.
The YB-52 had actually been ordered as the second of two XB-52s, but modifications and additional equipment installed during building resulted in enough differences to warrant a designation change. The first XB-52, 49-230, should have been the first to fly, but it was damaged during ground testing.
The Boeing XB-52 and YB-52 were prototypes for a very long range strategic bomber. Both were built with a tandem cockpit for the pilot and co-pilot, similar to the earlier B-47 Stratojet. The wings were swept and mounted high on the fuselage (“shoulder-mounted”). The eight turbojet engines were in in two-engine nacelles mounted on pylons, below and forward of the wings. This had the effect of preventing the airplane’s center of gravity from being too far aft, and also provided cleaner air flow across the wings. The B-52’s landing gear has four main struts with two wheels, each. They can turn to allow the airplane to face directly into the wind while the landing gear remain aligned with the runway for takeoff and landing. With the landing gear under the fuselage, the wings could be constructed with greater flexibility.
The YB-52 was 152 feet, 8 inches (46.533 meters) long with a wingspan of 185 feet, 0 inches (56.388 meters). The prototype’s overall height was 48 feet, 3.6 inches (14.722 meters). The vertical fin could be folded over to the right so that the B-52 could fit into a hangar. The total wing area was 4,000 square feet (371.6 square meters). The wings’ leading edges were swept aft to 36° 54′. Their angle of incidence was 6° and there was 2° 30′ dihedral. The YB-52 had an empty weight of 155,200 pounds (70,398 kilograms) and gross weight of 405,000 pounds (183,705 kilograms).
The YB-52 was powered by eight Pratt & Whitney Turbo Wasp YJ57-P-3 turbojet engines. The J57 was a two-spool, axial-flow turbojet developed from an experimental turboprop engine. It had 16-stage compressor section (9 low- and 7-high-pressure stages), 8 combustors and a 3-stage turbine section (1 high- and 2 low-pressure stages). The YJ57-P-3s had a continuous power rating of 8,700 pounds of thrust (38.70 kilonewtons). The YJ57-P-3 was 183.5 inches (4.661 meters) long, 41.0 inches (1.041 meters) in diameter and weighed 4,390 pounds (1,991 kilograms).
The YB-52 had a cruise speed of 519 miles per hour (835 kilometers per hour) and maximum speed of 611 miles per hour (983 kilometers per hour) at 20,000 feet (6,096 meters). Its range was 7,015 miles (11,290 kilometers).
The two prototypes were unarmed.
The B-52 was produced by Boeing at its plants in Seattle and Wichita from 1952 to 1962, with a total of 744 Stratofortresses built. The last version, the B-52H, entered service with the Strategic Air Command in 1960. The final B-52, B-52H-175-BW Stratofortress 61-0040, was rolled out at Wichita, Kansas, 26 October 1962. This airplane remains in service with the United States Air Force. The newest B-52 in service, 61-0040 is 56 years old and has flown more than 21,000 hours.
All previous versions, B-52A through B-52G, have long been retired to The Boneyard and scrapped. Of the 102 Boeing B-52H Stratofortress bombers, 76 are still in the active inventory. One, 61-007, known as Ghost Rider, was recently taken from Davis-Monthan and after an extensive restoration and update, returned to service.
The YB-52 prototype was retired to the National Museum of the United States Air Force in the late 1950s. By the mid-60s it was determined to be excess and was scrapped.
11 March 1957: The Boeing jet airliner prototype, the Model 367-80, N70700, made a transcontinental demonstration flight from Seattle’s Boeing Field (BFI) to Friendship National Airport (BWI), Baltimore, Maryland. The aircraft commander was Boeing’s Chief of Flight Test, Alvin Melvin (“Tex”) Johnston. Test pilots James Russell (“Jim”) Gannett and Samuel Lewis (“Lew”) Wallick, Jr., completed the flight crew. The flight covered 2,350 miles (3,782 kilometers) and took 3 hours, 48 minutes.
Jet Airliner Crosses U.S. At Record Clip
Seattle-To-Baltimore Flight Made In 3 Hours, 48 Minutes
WASHINGTON, March 12 (AP) A Boeing 707 jet passenger plane set a new transcontinental speed record for commercial aircraft yesterday, flying the 2,325 miles from Seattle to Baltimore in 3 hours and 48 minutes.
At one point it attained a speed of 698 miles an hour.
A.M. (Tex) Johnston, Boeing chief of flight tests, said he would fly back to Seattle tomorrow with stops at Chicago’s O’Hare Airport and at Denver. He planned a series of local flights for congressmen, Pentagon officials and experts.
The big plane averaged 612 miles an hour for its Puget Sound-to-Chesapeake Bay flight, and sliced 10 minutes off the unofficial transport plane record it set between Seattle and Washington, D.C., in 1955.
There were 52 persons aboard, all but 20 of them newsmen.
‘Jet Stream’ Helps
The 707 left Boeing Field at 10:06 a.m., EST. East of Spokane at 31,000 feet, it hit the “jet stream,” a vast windstream with speeds of up to 125 miles an hour.
These winds enabled the plane to attain supersonic speeds in relation to the ground over northwestern Montana and northern Idaho. However, the plane was actually in subsonic flight and did not break the “sound barrier.”
While in the jet stream, the plane’s peak air speed was 596 miles an hour, but at one point the stream boosted this by 102 miles an hour, for a top speed of 698 in relation to the ground.
Fighter Holds Record
The official transcontinental speed record was set by a one-place F-84F jet fighter two years ago—652½ mph for the 2,446 miles from Los Angeles to New York City. [LCOL Robert R. Scott, USAF, 9 March 1955—TDiA]
The fastest unofficial transcontinental crossing listed by the Defense Department: 715 mph for the 2,700 miles from Riverside, Calif., to Boston last Jan. 25, by a Boeing B-47 bomber.
The 707 is to be delivered to its first airline buyers—Pan American and American—late next year and early in 1959.
The plane’s cost varies from 4½ to 5½ million dollars, depending on size and range, Various models will carry from 120 to 162 passengers.
—Toledo Blade, Tuesday, 12 March 1957, Page 2 at Columns 2–4
Boeing had risked $16,000,000 in a private venture to build the Dash 80 in order to demonstrate its capabilities to potential civilian and military customers, while rivals Douglas and Lockheed were marketing their own un-built jet airliners. Put into production as the U.S. Air Force KC-135A Stratotanker air refueling tanker and C-135 Stratolifter transport, a civil variant was also produced as the Boeing 707 Stratoliner, the first successful jet airliner. Though they look very similar, the 707 is structurally different than the KC-135 and has a wider fuselage.
The prototype Boeing Model 367-80 was operated by a pilot, co-pilot and flight engineer. The airplane’s wing was mounted low on the fuselage and the engine nacelles were mounted on pylons under the wing, as they were on Boeing’s B-47 Stratojet and B-52 Stratofortress. The wings and tail surfaces were swept to 35° at 25% chord, and had 7° dihedral. The Dash 80 was 127 feet 10 inches (38.964 meters) long with a wingspan of 129 feet, 8 inches (39.522 meters) and overall height of 38 feet (11.582 meters). The tail span is 39 feet, 8 inches (12.090 meters). The empty weight of the 367-80 was 75,630 pounds (34,505 kilograms) and the gross weight, 190,000 pounds (86,183 kilograms).
N70700 was powered by four Pratt & Whitney Turbo Wasp JT3C engines. This engine is a civil variant of the military J57 series. It is a two-spool, axial-flow turbojet engine with a 16-stage compressor and 2-stage turbine. The JT3C-6 (used in the first production 707s) was rated at 11,200 pounds of thrust (49.82 kilonewtons), and 13,500 pounds (60.05 kilonewtons) with water/methanol injection). The JT3C is 11 feet, 6.6 inches (3.520 meters) long, 3 feet, 2.9 inches (0.988 meters) in diameter, and weighs 4,235 pounds (1,921 kilograms).
These gave the 367-80 a cruise speed of 550 miles per hour (885 kilometers per hour) and a maximum speed of 0.84 Mach (582 miles per hour, 937 kilometers per hour) at 25,000 feet (7,620 meters). The service ceiling was 43,000 feet (13,106 meters). Its range was 3,530 miles (5,681 kilometers).
Boeing continued to use the 367–80 for testing, finally retiring it 22 January 1970. At that time, its logbook showed 2,346 hours, 46 minutes of flight time (TTAF). It was flown to Davis-Monthan Air Force Base, Tucson, Arizona, and placed in storage. In 1990, Boeing returned it to flyable condition and flew it back it to Renton where a total restoration was completed. Many of those who had worked on the Dash 80, including Tex Johnston, were aboard.
The pioneering airplane was presented to the Smithsonian Institution and is on display at the National Air and Space Museum, Steven V. Udvar-Hazy Center. The Boeing 367-80 was designated an International Historic Mechanical Engineering Landmark by the American Society of Mechanical Engineers.
Highly recommended: Tex Johnston, Jet-Age Test Pilot, by A.M. “Tex” Johnston with Charles Barton, Smithsonian Books, Washington, D.C., 1991
18 February 1943: At 12:09 p.m., Boeing Aircraft Company Chief Test Pilot Edmund Turney (“Eddie”) Allen took off from Boeing Field, Seattle, Washington, in the Number 2 prototype XB-29 Superfortress long-range heavy bomber, serial number 41-0003. Allen’s co-pilot was engineering test pilot Robert R. Dansfield. The rest of the XB-29 flight crew were Charles Edmund Blaine, flight test engineer; Fritz Mohn, senior inspector; Vincent W. North, aerodynamicist; Harry William Ralston, radio operator; Barclay J. Henshaw, flight test analyst; Thomas R. Lankford, engineer; Robert Willis Maxfield, flight test engineer; Raymond Louis Basel, flight test engineer; Edward I. Wersebe, flight test engineer.
41-0003 had first flown on 30 December 1942, piloted by Allen. During that flight, the prototype bomber suffered a major engine fire and Eddie Allen’s performance in returning the airplane to the airport later earned him the U.S. Army’s Air Medal, awarded on the specific orders of President Harry S. Truman.
Problems with the XB-29s’ Wright R-3350-13 engines had caused major delays in the B-29 testing program. The Number 2 aircraft had its engines replaced with those from the first XB-29, 41-0002. By 18 February, 41-0003 had made only eight flights, with a total flight time of 7 hours, 27 minutes.
The ninth test flight of 41-0003 was planned to test the climb performance to 25,000 feet (7,620 meters) and to collect engine cooling data.
At 12:17 p.m., 41-0003 was climbing through 5,000 feet (1,524 meters) when the #1 engine (the outboard engine on the left wing) caught fire. The engine was shut down and CO2 fire extinguishers were activated. Eddie Allen began a descent and turned back toward Boeing Field.
The wind was out of the south at 5 miles per hour (2.24 meters per second) so it was decided to land on Runway 13, the southeast/northwest runway. At 12:24, radio operator Harry Ralston reported that the XB-29 was 4 miles (6.4 kilometers) northeast of the field at 1,200 feet (366 meters).
The airplane was in the landing pattern turning from the downwind leg to the base leg when at 12:25 an explosion occurred. Ralston was heard to say, “Allen, better get this thing down in a hurry. The wing spar is burning badly.”
In order to save weight, the crank case of the Wright R-3350 engine was made of magnesium, a flammable metal which burned at a very high temperature. With an engine on fire, the bomber’s wing structure was extremely vulnerable.
The prototype bomber was now shedding parts and left a trail behind it on the ground. The fire was now burning inside the fuselage. Three crew members bailed out but the altitude was too low and they were killed.
At 12:26 p.m., Boeing XB-29 41-0003 crashed into the Frye Meat Packing Plant, south of downtown Seattle, and exploded. Nearly 5,000 gallons (18,927 liters) of gasoline started a massive fire. The 8 men still aboard the prototype bomber were killed, as were 20 employees inside the building. A firefighter who responded was also killed.
Three XB-29 prototypes were built. The XB-29 was 98 feet, 2 inches (29.896 meters) long with a wing span of 141 feet, 3 inches (43.053 meters), and 27 feet, 9 inches (8.458 meters) high to the top of its vertical fin. The prototype bomber had a gross weight of 105,000 pounds (47,627.2 kilograms).
The XB-29 was powered by four 3,347.662-cubic-inch-displacement (54.858 liter) air-cooled, supercharged, Wright Aeronautical Division Cyclone 18 670C18H1 (R-3350-13) two-row 18-cylinder radial engines (also known as the Duplex-Cyclone) with a compression ratio of 6.85:1. The R-3350-13 had a Normal Power rating of 2,000 horsepower at 2,400 r.p.m., and 2,200 horsepower at 2,800 r.p.m. for takeoff, using 100 octane aviation gasoline. The engines turned 17-foot-diameter (5.182 meters) three-bladed Hamilton Standard Hydromatic constant-speed propellers through a 0.35:1 gear reduction. The R-3350-13 was 76.26 inches (1.937 meters) long, 55.78 inches (1.417 meters) in diameter, and weighed 2,668 pounds (1,210 kilograms).
The XB-29 had a maximum speed of 368 miles per hour (592 kilometers per hour) and cruised at 255 miles per hour (410 kilometers per hour). Its service ceiling was 32,100 feet (9,784 meters). The airplane was designed to carry 20,000 pounds (9,072 kilograms) of bombs.
The B-29 Superfortress was the most technologically advanced—and complex—aircraft of the War. It required the manufacturing capabilities of the entire nation to produce. Over 1,400,000 engineering man-hours had been required to design the prototypes. It would be manufactured by Boeing at Seattle and Renton, Washington and at Wichita, Kansas; by Glenn L. Martin Company at Omaha, Nebraska; and by Bell Aircraft Corporation, Atlanta, Georgia.
There were three XB-29 prototypes; 14 YB-29 pre-production test aircraft; 2,513 B-29; 1,119 B-29A; and 311 B-29B Superfortress aircraft. The bomber served during World War II and the Korean War and continued in active U.S. service until 1960.
The employees of the Boeing plant at Wichita, Kansas donated the money to build a B-29 to be named in honor of Eddie Allen. B-29-40-BW 42-24579 flew 24 combat missions. On its final mission over Tokyo, Japan, the Eddie Allen was so badly damaged that, though it was able to reach its base on the island of Tinian, it never flew again.