XB-70A-1-NA 62-0001 rollout at Air Force Plant 42, 11 May 1964. (North American Aviation, Inc.)
11 May 1964: At Air Force Plant 42 near Palmdale, a small city in the high desert of southern California, the first prototype North American Aviation XB-70A-1-NA Valkyrie, 62-0001, was rolled out. More than 5,000 people were there to watch.
In August 1960, the U.S. Air Force had contracted for one XB-70 prototype and 11 pre-production YB-70 development aircraft. By 1964, however, the program had been scaled back to two XB-70As and one XB-70B. Only two were actually completed.
“Ride of the Valkyrs” by John Charles Dollman, 1909. In Norse mythology, the valkyries were immortal female figures who chose who among those who had died in battle were worthy of being taken to Valhalla.
The B-70 was designed as a Mach 3+ strategic bomber capable of flying higher than 70,000 feet (21,336 meters). Like its contemporaries, the Lockheed Blackbirds, the Valkerie was so advanced that it was beyond the state of the art. New materials and processes had to be developed, and new industrial machinery designed and built.
The XB-70A is a very large aircraft with a canard-delta configuration, built primarily of stainless steel and titanium. It has twin vertical fins combining the functions of stabilizers and rudders. The XB-70A Valkyrie prototype is 193 feet, 5 inches (58.953 meters) long, including the pitot boom, with a wingspan of 105 feet, 0 inches (32.004 meters) and overall height of 30 feet, 9 inches (9.373 meters). The canard span is 28 feet, 10 inches (8.788 meters). The canard has flaps, while the delta wing used multiple separate elevons for pitch and roll control.
North American Aviation XB-70A-1-NA Valkyrie takes off at Edwards Air Force Base, 17 August 1965. (NASA)
The delta wing has an angle of incidence of 0° and its leading edges are swept to 65.57°, with 0° sweep at the trailing edge. The wings have a maximum of -2.60° of twist. The wings of 62-001 have no dihedral, but the second B-70, 62-0207, had 5° dihedral. The total wing area is 6,297.8 square feet (585.1 square meters).
The canard also has 0° of incidence and dihedral. Its leading edge is swept aft 31.70°, while the trailing edge sweeps forward 14.91°. The canard has a total area of 415.59 square feet (38.61 square meters). The canard flaps can be lowered to 20°.
The vertical fins have a height of 15 feet (4.572 meters). The leading edges are swept 51.77° and the trailing edges, 10.89°.
The B-70 was designed to “surf” on its own supersonic shock wave (this was called “compression lift”). The outer 20 feet (6.096 meters) of each wing could be lowered to a 25° or 65° angle for high speed flight. Although this did provide additional directional stability, it actually helped increase the compression lift, which supported up to 35% of the airplane’s weight in flight.
North American Aviation XB-70A-1-NA Valkyrie 62-0001. (U.S. Air Force)
The first prototype, 62-001, had an empty weight of 231,215 pounds (104,877 kilograms), and its maximum takeoff weight was 521,056 pounds (236,347 kilograms).
The XB-70A is powered by six General Electric YJ93-GE-3 engines, grouped together in the tail. These are single-spool, axial-flow, afterburning turbojet engines, which have an 11-stage compressor section and 2-stage turbine. The YJ93-GE-3 has a normal power rating of 17,700 pounds of thrust (78.734 kilonewtons); military power, 19,900 pounds (88.520 kilonewtons); and maximum power, 28,000 pounds (124.550 kilonewtons). All ratings are at 6,825 r.p.m. and are continuous. A special high-temperature fuel, JP-6, is required. The engine is 19 feet, 8.3 inches (6.002 meters) long, 4 feet, 6.15 inches (1.375 meters) in diameter, and weighs 5,220 pounds (2,368 kilograms).
Test firing one the 62-001’s General Electric YJ93-GE-3 afterburning turbojet engines. (LIFE Magazine)
62-0001 had a cruise speed of 1,089 knots (1,253 miles per hour/2,016 kilometers per hour) at 35,000 feet (10,688 meters), and maximum speed of 1,721 knots (1,980 miles per hour/3,187 kilometers per hour) at 79,050 feet (24,094 meters)—Mach 2.97. During flight testing, the XB-70A reached a maximum of Mach 3.08 (1,777 knots) with a sustained altitude of 74,000 feet (22,555 meters).
Fuel was carried in 11 internal tanks in the wings and fuselage and the maximum capacity was 43,646 gallons (165,218 liters), giving the bomber a combat range of 3,786 nautical miles (4,357 statute miles/7,012 kilometers).
The B-70 was designed to carry two B-53 two-stage radiation-implosion thermonuclear bombs in its internal bomb bay. A maximum of fourteen smaller weapons could be carried.
XB-70A-1 62-0001 first flew 21 September 1964, and exceeded Mach 3 for the first time on its 17th flight, 14 October 1965. Its final flight was 4 February 1969.
The second prototype, XB-70A-2-NA 62-0207, was destroyed in a midair collision. The third Valkyrie, XB-70B-NA 62-0208, was cancelled before completion.
62-0001 is in the collection of the National Museum of the United States Air Force. It has made 83 flights with just 160 hours, 16 minutes, total flight time.
XB-70A-1-NA Valkyrie 62-0001 in cruise at very high altitude, 1968. (NASA)
Convair B-36J-1-CF 52-2220 at NMUSAF, Wright-Patterson AFB, Ohio.
30 April 1959: Convair B-36J-1-CF Peacemaker, serial number 52-2220, landed at Wright-Patterson Air Force Base, Dayton, Ohio, completing the very last flight ever made by one of the giant Cold War-era bombers. It is on the collection of the National Museum of the United States Air Force.
Convair B-36J 52-2220 was among the last group of 33 B-36 bombers built. It was operated by an aircraft commander/pilot, co-pilot, two navigators, bombardier, two flight engineers, two radio operators, two electronic countermeasures operators and five gunners, a total 16 crewmembers. Frequently a third pilot and other additional personnel were carried.
Crew members pose in front of a Convair B-36F-1-CF Peacemaker, 49-2669, wearing David Clark Co. S-2 capstan-type partial pressure suits and early K-1 “split shell” 2-piece helmets for protection at high altitude. Front (L-R): G.L. Whiting, B.L. Woods, I.G. Hanten, and R.L. D’Abadie. Back (L-R):A.S. Witchell, J.D. McEachern, J.G. Parker and R. D. Norvell. (Jet Pilot Overseas)
The bomber is 162 feet, 1 inch (49.403 meters) long with a wingspan of 230 feet (70.104 meters) and overall height of 46 feet, 9 inches (14.249 meters). The empty weight is 171,035 pounds (77,580 kilograms) and combat weight is 266,100 pounds (120,700 kilograms). Maximum takeoff weight is 410,000 pounds (185,973 kilograms).
The B-36J has ten engines. There are six air-cooled, supercharged 4,362.49 cubic-inch-displacement (71.49 liter) Pratt & Whitney Wasp Major C6 (R-4360-53) four-row, 28-cylinder radial engines placed inside the wings in a pusher configuration. These had a compression ratio of 6.7:1 and required 115/145 aviation gasoline. The R-4360-53 had a Normal Power rating of 2,800 horsepower at 2,600 r.p.m. Its Military Power rating was 3,500 horsepower at 2,800 r.p.m., and 3,800 horsepower at 2,800 r.p.m. with water injection—the same for Takeoff. The engines turned three-bladed Curtiss Electric constant-speed, reversible propellers with a diameter of 19 feet, 0 inches (5.791 meters) through a 0.375:1 gear reduction. The R-4360-53 is 9 feet, 9.00 inches (2.972 meters) long, 4 feet, 7.00 inches (1.397 meters) in diameter, and weighs 4,040 pounds (1,832.5 kilograms).
Four General Electric J47-GE-19 turbojet engines are suspended under the wings in two-engine pods. The J47 is a single-shaft axial-flow turbojet engine with a 12-stage compressor section, 8 combustion chambers, and single-stage turbine. The J47-GE-19 was modified to run on gasoline and was rated at 5,200 pounds of thrust (23.131 kilonewtons).
The B-36J had a cruise speed of 203 miles per hour (327 kilometers per hour) and a maximum speed of 411 miles per hour (661 kilometers per hour) at 36,400 feet (11,905 meters) . The service ceiling was 39,900 feet (12,162 meters) and its range was 6,800 miles (10,944 kilometers) with a 10,000 pound (4,536 kilogram) bomb load. The maximum range was 10,000 miles (16,093 kilometers).
Convair B-36J-1-CF Peacemaker 52-2220. (San Diego Air and Space Museum Archives)
Designed during World War II, nuclear weapons were unknown to the Consolidated-Vultee engineers. The bomber was built to carry up to 86,000 pounds (39,009 kilograms) of conventional bombs in two bomb bays. It could carry the 43,600 pound (19,776.6 kilogram) T-12 Cloudmaker, a conventional explosive earth-penetrating bomb, or several Mk.15 thermonuclear bombs. By combining the bomb bays, one Mk.17 25-megaton thermonuclear bomb could be carried.
For defense, the B-36J had six retractable defensive gun turrets and gun turrets in the nose and tail. All 16 guns were remotely operated. Each position mounted two M24A1 20 mm autocannons. 9,200 rounds of ammunition were carried.
Convair B-36 Peacemakers at Davis-Monthan AFB, Tucson, Arizona. (U.S. Air Force)
Between 1946 and 1954, 384 B-36 Peacemakers were built. They were never used in combat. Only five still exist.
Convair B-36J-1-CF 52-2220 being moved from Building 1 to Building 3 at the National Museum of the United States Air Force, October 2002. (U.S. Air Force)
The Boeing YB-52 Stratofortress, 49-231, takes off from Boeing Field at 11:08 a.m., 15 April 1952. (Robert F. Dorr Collection)
15 April 1952: At 11:08 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.
Alvin M. “Tex” Johnston, Boeing Chief of Flight Test, after the first flight of the Boeing XB-52 Stratofortress prototype, 2 October 1952. (LIFE via Jet Pilot Overseas)
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.
Boeing YB-52 Stratofortress 49-231. (Boeing)
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.
Boeing XB-52 Stratofortress 49-230. (U. S. Air Force)
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.
Boeing YB-52 Stratofortress 49-231. (U.S. Air Force)
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.
Boeing YB-52 Stratofortress 49-231. (U.S. Air Force)
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 62 years old and has flown more than 21,000 hours.
The Boeing YB-52 Stratofortress, 49-231, lands on Rogers Dry Lake, circa 1953. (U.S. Air Force 071204-F-9999J-039)
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.
Left to right: Captain William Magruder, USAF; Boeing Chief Test Pilot Alvin M. Johnston; and Lieutenant Colonel Guy M. Townsend, USAF, with the Boeing YB-52 Stratofortress, 49-231. (Boeing)
Boeing B-52H-135-BW Stratofortress 60-0006. (United States Air Force)
6 March 1961: The B-52H is the final version of the Boeing B-52 Stratofortress intercontinental strategic bomber. There are discrepancies as to the date of its first flight, with sources varying by as much as eight months. One very reliable source writes that the flight took place on 20 July 1960. A U.S. Air Force publication says that it was in March 1961, and another source (Boeing) says that it was 6 March 1961. An article in The Kansas City Times confirms the date:
B-52H IS TEST FLOWN
Initial Flight Is Made by Bomber at Wichita
Wichita, March 6.(AP)—The first of this nation’s newest missile bombers, the global B-52H, took to the air in its initial flight today.
A 6-man test crew of the Boeing Airplane company manned the production model super bomber, which is capable of flying 650 miles an hour over an 11,000-mile range.
The bomber will carry four Douglas Skybolt missiles.
—The Kansas City Times, Vol. 124, No. 56, 7 March 1961, Page 21, Columns 7–8
The U.S. Air Force contracted 62 B-52H Stratofortresses, serial numbers 60-0001 through 60-0062, on 6 May 1960. A second group of 40, serials 61-0001 through 61-0040, were ordered later. All were built at the Boeing Wichita plant.
A fourth source identifies the aircraft in the photograph above, Boeing B-52H-135-BW Stratofortress 60-0006, (Boeing serial number 464-371) as the first B-52H to fly. The existence of a nice aerial portrait suggests that this may be correct.
The B-52H, like the B-52G, is a re-engineered aircraft, structurally different from the XB-52, YB-52, and B-52A–B-52F Stratofortress variants. It is lighter, carries more internal fuel, giving it a longer unrefueled range, and is strengthened for low-altitude flight. The B-52H is also equipped with quieter, more efficient turbofan engines.
A Boeing B-52H Stratofortress carries four Douglas GAM-87 Skybolt ALBMs. (U.S. Air Force)
The B-52H was developed to carry four Douglas GAM-87 Skybolt air-launched ballistic missiles on pylons mounted under the wings, inboard of the engines. The Skybolt was armed with a 1-megaton W-59 thermonuclear warhead. The program was cancelled, however, and the North American Aviation AGM-28 Hound Dog air-launched cruise missile was used instead. (Interestingly, the Hound Dog’s Pratt & Whitney J52-P-3 turbojet engine could be used to supplement the B-52’s takeoff thrust, and then refueled from the bomber’s tanks before being air-launched.)
Boeing B-52G-105-BW Stratofortress 58-0216 armed with two North American Aviation AGM-28 Hound Dog ALCMs. (U.S. Air Force)
The B-52H is a sub-sonic, swept wing, long-range strategic bomber. It was originally operated by a crew of six: two pilots, a navigator and a radar navigator, an electronic warfare officer, and a gunner. (The gunner was eliminated after 1991). The airplane is 159 feet, 4 inches (48.565 meters) long, with a wing span of 185 feet (56.388 meters). It is 40 feet, 8 inches (12.395 meters) high to the top of the vertical fin. The B-52H uses the vertical fin developed for the B-52G, which is 22 feet, 11 inches (6.985 meters) tall. This is 7 feet, 8 inches (2.337 meters) shorter than the fin on the XB-52–B-52F aircraft. The bomber has an empty weight of 172,740 pounds (78,354 kilograms) and its Maximum Takeoff Weight (MTOW) is 488,000 pounds (221,353 kilograms).
The most significant difference between the B-52H and the earlier Stratofortresses is the replacement of the eight Pratt & Whitney J57-series turbojet engines with eight Pratt & Whitney Turbo Wasp JT3D-2 (TF33-P-3) turbofans, which are significantly more efficient. They are quieter and don’t emit the dark smoke trails of the turbojets. The TF-33 is a two-spool axial-flow turbofan engine with 2 fan stages, a 14-stage compressor section (7-stage intermediate pressure, 7-stage high-pressure) and and a 4-stage turbine (1-stage high-pressure, 3-stage low-pressure). Each engine produces a maximum of 17,000 pounds of thrust (75.620 kilonewtons). The TF33-P-3 is 11 feet, 10 inches (3.607 meters) long, 4 feet, 5.0 inches (1.346 meters) in diameter and weighs 3,900 pounds (1,769 kilograms).
The B-52H has a cruise speed of 525 miles per hour (845 kilometers per hour). It has a maximum speed of 632 miles per hour (1,017 kilometers per hour) at 23,800 feet (7,254 meters)—0.908 Mach. The service ceiling is 47,700 feet (14,539 meters). The unrefueled range is 8,000 miles (12,875 kilometers). With inflight refueling, its range is limited only by the endurance of its crew.
The B-52H was armed with a 20 mm M61A1 Vulcan 6-barreled rotary cannon in place of the four .50-caliber machine guns of the earlier variants. The gun was removed after 1991.
The B-52H was armed with a 20mm M61A1 Vulcan six-barreled rotary cannon in a remotely-operated tail turret. The gun had a rate of fire of 4,000 rounds per minute, and had a magazine capacity of 1,242 rounds. After 1991, the gun and its radar system were removed from the bomber fleet. The flight crew was reduced to five.
The B-52H can carry a wide variety of conventional free-fall or guided bombs, land-attack or anti-ship cruise missiles, and thermonuclear bombs or cruise missiles. These can be carried both in the internal bomb bay or on underwing pylons. The bomb load is approximately 70,000 pounds (31,751 kilograms).
A Boeing B-52H Stratofortress dropping forty-five M117 750-pound (340 kilogram) general purpose bombs. (Senior Airman Carlin Leslie, U.S. Air Force)
The first of 102 B-52H Stratofortresses entered service on 9 May 1961. The last one, 61-0040, was rolled out 26 October 1962. Beginning in 2009, eighteen B-52H bombers were placed in climate-controlled long term storage at Tinker Air Force Base, Oklahoma. As of December 2015, fifty-eight of the bombers remained in the active fleet of the United States Air Force and eighteen are assigned to the Air Force Reserve. In 2014, the entire fleet began a major avionics upgrade. B-52Hs remaining in the Air Force inventory will be upgraded with new engines, new radar, communications and navigation equipment, and will be redesignated B-52J. The B-52 is expected to remain in service until 2040.
An ordnance crew loads a rotary launcher with 8 cruise missiles into the bomb bay of a B-52H Stratofortress. (Senior Airman Amber Ashcraft/U.S. Air Force)
60-0006, the first B-52H to fly, crashed while making a ground-controlled (GCA) approach to Wright Patterson Air Force Base, Dayton, Ohio, at 2:07 a.m., 30 May 1974. The bomber’s rudder and elevators failed. Although 60-0006 was destroyed, all seven airmen on board, Captains Charles Brown, Robert E. Smith, William G. Heckathorn, Paul C. Hoffman, 1st Lieutenants John D. Weaver, James R. Villines, and 2nd Lieutenant Robert E. Pace, survived the accident without serious injuries.
Wreck of Boeing B-52H-135-BW Stratofortress 60-0006 at Wright-Patterson AFB, 30 May 1974. Two AGM-28 Hound Dog ACLMs are lying in the background. (Dayton Daily News Archive)A Boeing B-52H Stratofortress during a deterrent patrol near the Democratic People’s Republic of North Korea, 2016. The bomber is carrying a load of Mk.84 2,000-pound JDAM “smart” bombs. (Master Sgt. Lance Cheung, U.S. Air Force)Boeing B-52H-165-BW Stratofortress 61-0007 takes off at Tinker Air Force Base on a functional test flight, 30 August 2016. The airplane, named “Ghost Rider,” was overhauled after being stored for eight years at The Boneyard, Davis-Monthan Air Force Base, Arizona. 61-0007 is the very first B-52 to have been “regenerated.” (Kelly White/U.S. Air Force)
The first Boeing B-47A Stratojet, 49-1900. (U.S. Air Force)
1 March 1950: The first production Boeing B-47 Stratojet, B-47A 49-1900 (Boeing serial number 450001), was rolled off the assembly line at Boeing’s Wichita, Kansas, Plant II.
The Wichita Eagle reported:
“FIRST B-47A PRODUCTION MODEL SHOWN—First production model of the B-47A Stratojet bomber is shown above, surrounded by Boeing-Wichita officials as it rolled from the assembly line at the local plant Wednesday. (Other pictures on Page 4.)”
First Stratojet Rolls Off B-47 Assembly Line Here
Boeing-Wichita Puts New Model Into Production
Six-Jet Speed Bomber Even More Powerful Than Its Predecessor
Boeing-Wichita’s first B-47 Stratojet bomber rolled off final assembly Wednesday at the local plant, less than 18 months after the Air Force gave the go-ahead signal to build the big, six-jet, swept-wing bomber here.
The airplane was given to an Air Force aircraft engineering inspection board. The board will examine it for a week, alterations will be made in the shops, if any are needed, and it will be ready to fly.
The first production model of the already-famous bomber has been designated the B-47A. It is almost identical in appearance to the experimental XB-47s, which were built in the Seattle, Wash., plant of the Boeing Aircraft Company, but the resemblance ends there.
More Powerful than XB-47
This is a more powerful airplane, Boeing officials say. Instead of the six jet engines of 4,000 pounds thrust each which powered the first experimental Stratojet, this first production model is powered by six jet engines of 5,200 pounds thrust each.
Additional internal improvements have been made based on experience gained in the XB-47 flight test program, which was moved from Moses Lake, Wash., with the arrival here of the first XB-47. The second “X” came here in October.
Recently one of the experimental models got a test of rocket assisted takeoff at Municipal Airport where an expansion program costing nearly $1,000,000 has been started to accommodate the B-47 flight testing program.
Holds Speed Record
The first production model climaxes more than six years of jet bomber design study and development by Boeing. The first experimental flight was made at Moses Lake Dec. 17, 1947, more than 26 months ago.
In February, 1949, an XB-47 was piloted to an unofficial, all-time, all-type transcontinental speed record. It flew 2,289 miles from Moses lake to Andrews Air Force Base, in three hours, 46 minutes. The average speed was 607.8 miles per hour. The record-breaking airplane was equipped with the smaller jet engines.
At Boeing-Wichita, closed down following World War II when 1,644 B-29 Superforts were built there, the first production model climaxes a reactivation begun in March, 1948.
Six months later came the Air Force “letter of intent” and B-47 Stratojet production got underway in Wichita.
“ASSEMBLY LINE IS SHOWN—Part of the assembly line which produced Boeing-Wichita’s first Stratojet six engine bomber is shown above. Three more Stratojets, designated B-47A, are shown being assembled.”“CLOSE-UP OF B-47A SHOWN—Here’s a close-up of the first production model of the B-47A Stratojet bomber which rolled from the Boeing-Wichita assembly line Wednesday. In the center of the crowd, above, J. Earl Schaefer, vice president and general manager of Boeing, happily makes the rounds congratulating workers and officials who built the bomber.”
—The Wichita Eagle, Vol. 24, Number 50, Wednesday 1 March 1950, Page 1, Column 7, and Page 4, Columns 5–8
Boeing B-47A Stratojet 49-1900. (U.S. Air Force 061024-F-1234S-007)
B-47A 49-1900 made its first flight 25 June 1950.
Designed by Boeing, the Stratojet was a high-subsonic-speed strategic bomber and reconnaissance aircraft, in service from 1951 until 1977. The B-47 could fly higher and faster than jet fighters of the early 1950s, and it was also highly maneuverable. The B-47 was flown by a two pilots in a tandem cockpit. A navigator/bombardier was at a station in the nose. The crew area was pressurized.
This photograph shows Boeing B-47A Stratojet 49-1905. The single-piece plexiglas nose of 49-1900 has been replaced by four separate windows. (U.S. Air Force)
The Boeing B-47A Stratojet was the first production model of the B-47 series. The B-47A was 106 feet, 10 inches (32.563 meters) long with a wingspan of 116 feet, 0 inches (35.357 meters), and an overall height of 27 feet, 11 inches (8.509 meters). The wings were shoulder-mounted with the leading edges swept aft to 36° 37′. Their angle of incidence was 2° 45′ and there was no dihedral. (The wings were very flexible, showing marked anhedral on the ground and flexing upward when in flight.) The B-47A had an empty weight of 73,240 pounds (33,221 kilograms), and a maximum takeoff weight of 157,000 pounds (71,214 kilograms).
The B-47A was powered by six General Electric J47-GE-11 turbojet engines in four nacelles mounted on pylons below the wings. This engine had a 12-stage axial-flow compressor, eight combustion chambers, and single-stage turbine. The J47-GE-11 had a maximum power rating of 5,610 pounds of thrust (24.95 kilonewtons) at 8,030 r.p.m. (30-minute limit), and continuous power rating of 4,860 pounds (21.62 kilonewtons) at 7,450 r.p.m. It had a maximum diameter of 3 feet, 3.0 inches (0.991 meters), length of 12 feet, 0.0 inches (3.658 meters), and weighed 2,475 pounds (1,123 kilograms).
The B-47A was also equipped with 18 Aerojet 14AS1000 solid-fuel rocket engines (ATO) located in the aft fuselage. These produced a maximum 18,000 pounds of thrust (80.07 kilonewtons) for 14 seconds. (49-1901 did not have provisions for ATO.)
A Boeing B-47A Stratojet demonstrates a rocket-assisted takeoff (ATO) The configuration of windows in the nose differs from that of 49-1905, in the image above. (McMahan Photo Archive)
The B-47A Stratojet had maximum speed of 474 knots (545 statute miles per hour/878 kilometers per hour) at 35,000 feet (10,668 meters). The bomber’s speed was limited to 0.815 Mach due to buffeting. The service ceiling was 46,200 feet (14,082 meters) and the combat ceiling, 44,300 feet (13,503 meters).
The B-47A had a maximum ferry range of 2,856 nautical miles (3,287 statute miles/5,289 kilometers) at 424 knots, and a combat radius with a 10,000 pound (4,536 kilograms) bomb load of 1,350 nautical miles (1,554 statute miles/2,500 kilometers). The maximum fuel load was 9,518 gallons (36,030 liters) carried in four fuselage tanks.
The B-47A had space and provisions to mount two Browning AN-M3 .50-caliber machine guns in a remotely-operated tail turret.
Boeing B-47A Stratojet 49-1900 with its bomb bay doors open. (Mary Evans Picture Library)
The B-47A could carry a single T-14 22,000 pound (9,979 kilogram) or T-10 12,000 pound (5,443 kilogram) general purpose bomb (both were U.S. versions of the British World War II Grand Slam and Tallboy bombs); up to 16 1,000 pound (454 kilogram) general purpose bombs; or one 10,000 pound (4,536 kilogram) nuclear bomb.
The B-47As were considered as training aircraft and most were assigned to the 306th Bomb Wing (Medium) at MacDill Air Force Base, Florida.
NACA 150, the first Boeing B-47A Stratojet,49-1900, decelerates after landing at Edwards Air Force Base, California, circa 1953. (NASA Photo E-1004)
The first B-47A, 49-1900, was tested by the U.S. Air Force at Wright Field, Ohio, and then at the National Advisory Committee for Aeronautics’ Langley Memorial Aeronautical Laboratory at Hampton, Virginia, where it was identified as NACA 150. It was later transferred to the NACA High Speed Flight Research Station at Edwards Air Force Base in the high desert of southern California. It flew there from 1953 to 1957. 49-1900 was placed in storage at Davis-Monthan Air Force Base, Tucson, Arizona, 28 February 1958.
Boeing B-47A Stratojet 49-1900 as NACA 150, at Edwards AFB, California. Note the reconfigured nose. (NASA)
B-47A production ended in June 1951, as production shifted to the B-47B. Just ten B-47As were built.
A total of 2,032 B-47s were built by a consortium of three aircraft manufacturers: Boeing Airplane Company, Wichita, Kansas; Douglas Aircraft Company, Tulsa, Oklahoma; Lockheed Aircraft Company, Marietta, Georgia.
Seven Boeing B-47A Stratojets at the Boeing Airplane Co. Plant II, Wichita, Kansas, 26 June 1951. (U.S. Air Force)
