Tag Archives: General Electric YJ93-GE-3

21 September 1964

North American Aviation XB70A-1-NA 62-001 takes off for the first time, 21 September 1964. (U.S. Air Force)
North American Aviation XB70A-1-NA 62-0001 takes off for the first time, 21 September 1964. (U.S. Air Force)

21 September 1964: The first prototype North American Aviation XB-70A-1-NA Valkyrie, serial number 62-0001, flown by Chief Test Pilot Alvin S. White and Colonel Joseph F. Cotton, U.S. Air Force, made its first flight from Air Force Plant 42, Palmdale, California, to Edwards Air Force Base.

Originally a prototype Mach 3 strategic bomber, 62-0001 (also known as AV-1) and it’s sister ship, XB-70A-2-NA, 62-0207, (AV-2), were built and used by the Air Force and NASA as high-speed research aircraft. The third Valkyrie, XB-70B-NA 62-0208 (AV-3), was never completed.

Major Joseph F. Cotton, USAF, and Alvin S. White, North American Aviation, with the XB-70A Valkyrie. (Autographed photograph courtesy of Neil Corbett, TEST & RESEARCH PILOTS, FLIGHT TEST ENGINEERS)
Colonel Joseph F. Cotton, USAF, and Alvin S. White, North American Aviation, with an XB-70A Valkyrie. (Autographed photograph courtesy of Neil Corbett, TEST & RESEARCH PILOTS, FLIGHT TEST ENGINEERS)

62-0001 was the first of three prototype Mach 3+ strategic bombers. (The third prototype, XB-70B 62-0208, was not completed.) The Valkyrie utilized the most advanced technology available. Materials and manufacturing techniques had to be developed specifically to build this airplane. It is a large delta wing airplane with a forward canard and two vertical fins. 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.

The XB-70A is 185 feet, 10 inches (56.642 meters) long with a wingspan of 105 feet (32.004 meters) and overall height of 30 feet, 9 inches (9.373 meters). The delta wing had 0° angle of incidence and 0° dihedral. (The second XB-70A had 5° dihedral.) The wing has 3.0° negative twist. At 25% chord, the wing has 58.0° sweepback. Total wing area is 6,297 square feet (585 square meters). The Valkyrie has a empty weight of 231,215 pounds (104,877 kilograms), and maximum takeoff weight (MTOW) of 521,056 pounds (2236,347 kilograms).

It is powered by six General Electric YJ93-GE-3 turbojet engines. The J93 is an afterburning single-shaft axial-flow turbojet with an 11-stage compressor section and two-stage turbine. It has a Normal Power rating of 17,700 pounds of thrust (78.73 kilonewtons), 19,900 pounds (88.52 kilonewtons), Military, and 28,000 pounds (124.55 kilonewtons) Maximum. (All ratings are continuous, at 6,825 r.p.m.) The YJ93-GE-3 is 236.3 inches (6.002 meters) long, 54.15 inches (1.375 meters) in diameter, and weighs 5,220 pounds (2,368 kilograms).

A Boeing B-52 Stratofortress flies formation with North American Aviation XB-70A Valkyrie 62-0001, approaching the runway at Edwards Air Force Base, California. (U.S. Air Force)

The maximum speed achieved was Mach 3.1 (1,787 knots/2,056 miles per hour, or 3,309 kilometers per hour) at 73,000 feet (22,250 meters). Its mission maximum speed is 1,721 knots (1,980 miles per hour/3,187 kilometers per hour) at 79,050 feet (29,094 meters). The XB-70A has a rate of climb of 33,000 feet per minute (168 meters per second). The service ceiling is 79,000 feet (24,079 meters).

The Valkyrie has a maximum fuel capacity of 43,646 gallons (165,218 liters) JP-5 or JP-6, carried in 11 tanks throughout the fuselage and wings. It also carries 42.4 gallons (161 liters) of engine oil. The maximum range is 2,969 nautical miles (3,417 statute miles/5,499 kilometers).

North American Aviation XB-70A Valkyrie 62-0001 made 83 flights with a total of 160 hours, 16 minutes flight time. 62-0001 is on display at the National Museum of the United States Air Force, Wright-Patterson Air Force Base, Ohio.

North American Aviation XB-70A Valkyrie 62-0001 lands at Edwards Air Force Base at the end of its first flight, 21 September 1964. (U.S. Air Force)
North American Aviation XB-70A-1-NA Valkyrie 62-0001 just before landing at Runway 4 Right, Edwards Air Force Base, ending of its first flight, 21 September 1964. A Piasecki HH-21B rescue helicopter hovers over the adjacent taxiway. (U.S. Air Force)

© 2024, Bryan R. Swopes

11 May 1964

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)
XB-70A-1-NA Valkyrie 62-0001 in cruise at very high altitude, 1968. (NASA)

© 2019, Bryan R. Swopes

4 February 1969

North American Aviation XB-70A-1-NA Valkyrie 62-0001. (U.S. Air Force)

4 February 1969: The North American Aviation XB-70A-1-NA Valkyrie, 62-0001, made its very last flight from Edwards Air Force Base, California, to Wright-Patterson Air Force Base, Ohio. NASA Research Test Pilot Fitzhugh L. Fulton, Jr., Lieutenant Colonel, U.S. Air Force (Retired), and Lieutenant Colonel Emil Sturmthal, U.S. Air Force, were the flight crew for this final flight.

On arrival at Wright-Patterson, Fulton closed out the log book and handed it over to the curator of the National Museum of the United States Air Force.

The Mach 3+ prototype strategic bomber and high-speed, high-altitude research airplane made its first flight 21 September 1964. It completed 83 flights for a total of 160 hours, 16 minutes of flight time.

Lieutenant Colonel Emil Sturmthal, USAF and Fitzhugh Fulton, NASA, with the North American Aviation XB-70A-1-NA 62-0001 at Edwards AFB, California. (Chris Walmsley/Rockwell International)
Lieutenant Colonel Emil Sturmthal, USAF and Fitzhugh Fulton, NASA, with the North American Aviation XB-70A-1-NA 62-0001 at Edwards AFB, California. (Chris Walmsley/Rockwell International)

62-0001 was the first of three prototype Mach 3+ strategic bombers. (The third prototype, XB-70B 62-0208, was not completed.) The Valkyrie utilized the most advanced technology available. Materials and manufacturing techniques had to be developed specifically to build this airplane. It is a large delta wing airplane with a forward canard and two vertical fins. 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.

The XB-70A is 185 feet, 10 inches (56.642 meters) long with a wingspan of 105 feet (32.004 meters) and overall height of 30 feet, 9 inches (9.373 meters). The delta wing had 0° angle of incidence and 0° dihedral. (The second XB-70A had 5° dihedral.) The wing has 3.0° negative twist. At 25% chord, the wing has 58.0° sweepback. Total wing area is 6,297 square feet (585 square meters). The Valkyrie has a empty weight of 231,215 pounds (104,877 kilograms), and maximum takeoff weight (MTOW) of 521,056 pounds (236,347 kilograms).

It is powered by six General Electric YJ93-GE-3 turbojet engines. The J93 is an afterburning single-shaft axial-flow turbojet with an 11-stage compressor section and two-stage turbine. It has a Normal Power rating of 17,700 pounds of thrust (78.73 kilonewtons), 19,900 pounds (88.52 kilonewtons), Military, and 28,000 pounds (124.55 kilonewtons) Maximum. (All ratings are continuous, at 6,825 r.p.m.) The YJ93-GE-3 is 236.3 inches (6.002 meters) long, 54.15 inches (1.375 meters) in diameter, and weighs 5,220 pounds (2,368 kilograms).

The maximum speed achieved was Mach 3.1 (1,787 knots/2,056 miles per hour, or 3,309 kilometers per hour) at 73,000 feet (22,250 meters). Its mission maximum speed is 1,721 knots (1,980 miles per hour/3,187 kilometers per hour) at 79,050 feet (29,094 meters). The XB-70A has a rate of  climb of 33,000 feet per minute (168 meters per second). The service ceiling is 79,000 feet (24,079 meters).

The Valkyrie has a maximum fuel capacity of 43,646 gallons (165,218 liters) JP-5 or JP-6, carried in 11 tanks throughout the fuselage and wings. It also carries 42.4 gallons (161 liters) of engine oil. The maximum range is 2,969 nautical miles (3,417 statute miles/5,499 kilometers).

The second Valkyrie, XB-70A-2-NA 62-0207, was destroyed when it crashed after a mid-air collision with a Lockheed F-104N Starfighter flown by NASA Chief Research Test Pilot Joseph A. Walker, 8 June 1966. Both Walker and the B-70’s co-pilot, Major Carl S. Cross, U.S. Air Force, were killed.

XB-70A Valkyrie 62-0001 is in the collection of the National Museum of the United States Air Force.

North American Aviation XB-70A-1-NA Valkyrie 62-0001 at Wright-Patterson Air Force Base, Ohio. (U.S. Air Force)
North American Aviation XB-70A-1-NA Valkyrie 62-0001 at Wright-Patterson Air Force Base, Ohio. (U.S. Air Force)
 North American Aviation XB-70A-1-NA Valkyrie 62-0001 at Wright-Patterson Air Force Base, Ohio. This photograph shows the twelve elevons that act as elevators, flaps and ailerons, the swiveling action of the vertical fins, open drag chute doors and the variable exhaust outlets. (U.S. Air Force).
North American Aviation XB-70A-1-NA Valkyrie 62-0001 at Wright-Patterson Air Force Base, Ohio. This photograph shows the twelve elevons that act as elevators, flaps and ailerons, the swiveling action of the vertical fins, open drag chute doors and the variable exhaust outlets. (U.S. Air Force).

© 2024, Bryan R. Swopes