Tag Archives: Allison Engineering Co.

9 September 1940

North American Aviation NA-73X prototype, NX19998, at Mines Field, California, 9 September 1940. (North American Aviation, Inc.)

9 September 1940: North American Aviation completed assembly of the NA-73X, the first prototype of the new Mustang Mk.I fighter for the Royal Air Force. This was just 117 days after the British Purchasing Commission had authorized the construction of the prototype. The airplane was designed by a team led by Edgar Schmued. The 1,150-horsepower Allison V-12 engine had not yet arrived, so the NA-73X was photographed with dummy exhaust stacks. The prototype’s company serial number was 73-3097. It had been assigned a civil experimental registration number, NX19998.

The NA-73X was a single-seat, single-engine, low wing monoplane with retractable landing gear. It was primarily of metal construction, though the flight control surfaces were fabric covered. The airplane was designed for the maximum reduction in aerodynamic drag.  The Mustang was the first airplane to use a laminar-flow wing. The fuselage panels were precisely designed and very smooth. Flush riveting was used. The coolant radiator with its intake and exhaust ducts was located behind and below the cockpit. As cooling air passed through the radiator it was heated and expanded, so that as it exited, it actually produced some thrust.

The prototype was 32 feet, 2⅝ inches (9.820 meters) long, with a wing span of 37 feet, 5/16 inch (11.286 meters). Empty weight of the NA-73X was 6,278 pounds (2,848 kilograms) and normal takeoff weight was 7,965 pounds (3,613 kilograms).

Aeronautical Engineer Edgar Schmued with a North American P-51-2-NA (Mustang Mk.IA), 41-37322. (San Diego Air and Space Museum Archives)

The NA-73X was powered by a liquid-cooled, supercharged, 1,710.60-cubic-inch-displacement (28.032 liter) Allison Engineering Company V-1710-F3R (V-1710-39) single overhead cam 60° V-12 engine, with four valves per cylinder and a compression ratio of 6.65:1. It used a single-stage, single-speed supercharger. This was a right-hand tractor engine (the V-1710 was built in both right-hand and left-hand configurations) which drove a 10 foot, 6 inch (3.200 meter) diameter, three-bladed, Curtiss Electric constant-speed propeller through a 2.00:1 gear reduction.

The V-1710-39 had a Normal Power rating of 880 horsepower at 2,600 r.p.m. at Sea Level; Take Off Power rating of 1,150 horsepower at 3,000 r.p.m. at Sea Level, with 44.5 inches of manifold pressure (1.51 Bar), 5 minute limit; and a War Emergency Power rating of 1,490 horsepower at 3,000 r.p.m., with 56 inches of manifold pressure (1.90 Bar). The V-1710-F3R was 7 feet, 4.38 inches (2.245 meters) long, 3 feet, 0.64 inches (0.931 meters) high, and 2 feet, 5.29 inches (0.744 meters) wide. It had a dry weight of 1,310 pounds (594 kilograms).

U.S. Army Air Corps flight tests of the fully-armed production Mustang Mk.I (XP-51 41-038), equipped with the V-1710-39 and a 10 foot, 9-inch (3.277 meters) diameter Curtiss Electric propeller, resulted in a maximum speed of 382.0 miles per hour (614.8 kilometers per hour) at 13,000 feet (3,962 meters). The service ceiling was 30,800 feet (9,388 meters) and the absolute ceiling was 31,900 feet (9,723 meters).

The Curtiss P-40D Warhawk used the same Allison V-1710-39 engine as the XP-51, as well as a three-bladed Curtiss Electric propeller. During performance testing at Wright Field, a P-40D, Air Corps serial number 40-362, weighing 7,740 pounds (3,511 kilograms), reached a maximum speed of 354 miles per hour (570 kilometers per hour) at 15,175 feet (4,625 meters). Although the Mustang’s test weight was 194 pounds (88 kilograms) heavier, at 7,934 pounds (3,599 kilograms), the Mustang was 28 miles per hour (45 kilometers per hour) faster than the Warhawk. This demonstrates the effectiveness of the Mustang’s exceptionally clean design.

Only one NA-73X was built. It made its first flight 26 October 1940 with test pilot Vance Breese. The prototype suffered significant damage when it overturned during a forced landing, 20 November 1941. NX19998 was repaired and flight testing resumed. The prototype’s final disposition is not known.

Originally ordered by Great Britain, the Mustang became the legendary U.S. Army Air Corps P-51 Mustang. A total of 15,486 Mustangs were built by North American Aviation at Inglewood, California and Dallas, Texas. Another 200 were built in Australia by the Commonwealth Aircraft Corporation.

The P-51 remained in service with the U.S. Air Force until 27 January 1957 when the last one, F-51D-30-NA 44-74936, was retired from the 167th Fighter Squadron, West Virginia Air National Guard. It was then transferred to the National Museum of the United States Air Force at Wright-Patterson Air Force Base, where it is on display.

North American Aviation NA-73X prototype, left front quarter view. (North American Aviation, Inc.)
North American Aviation NA-73X prototype, NX19998, left front quarter view. (North American Aviation, Inc.)

© 2017, Bryan R. Swopes

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26 April 1939

Curtiss-Wright’s Chief Test Pilot, H. Lloyd Child, in the cockpit of a P-40 Warhawk, circa 1940. (Rudy Arnold Collection/NASM)

26 April 1939: The United States Army Air Corps placed an order for 524 Curtiss-Wright P-40 Warhawks. This was the largest production order for any U.S.-built fighter since World War I. The total cost was $12,872,398.¹

The order was authorized by the Air Corps Expansion Act, approved by Congress 3 April, and signed by President Roosevelt on 26 April 1939.

The Curtiss-Wright Corporation Hawk 81 (P-40 Warhawk) was a single-seat, single-engine pursuit, designed by Chief Engineer Donovan Reese Berlin. It was developed from Berlin’s radial-engine P-36 Hawk. The P-40 was a low-wing monoplane of all-metal construction and used flush riveting to reduce aerodynamic drag. It had an enclosed cockpit and retractable landing gear (including the tail wheel). Extensive wind tunnel testing at the NACA Langley laboratories refined the airplane’s design, significantly increasing the top speed.

The first production Curtiss-Wright P-40 Warhawk, 39-156. (U.S. Air Force)

The new fighter was 31 feet, 8-9/16 inches (9.666 meters) long with a wingspan of 37 feet, 3½ inches (11.366 meters) and overall height of 9 feet, 7 inches (2.921 meters). The P-40’s empty weight was 5,376 pounds (2,438.5 kilograms) and gross weight was 6,787 pounds (3,078.5 kilograms).

The P-40 was powered by a liquid-cooled, supercharged, 1,710.597-cubic-inch-displacement (28.032 liter) Allison Engineering Co. V-1710-C15 (V-1710-33). This was a single overhead cam (SOHC) 60° V-12 engine designed by Harold Caminez, Allison’s chief engineer. The V-1710-33 had a compression ratio of 6.65:1. It was rated at 930 horsepower at 2,600 r.p.m. at 12,800 feet (3,901 meters), and 1,040 horsepower at 2,800 r.p.m. for takeoff, burning 100-octane gasoline. The engine turned a three-bladed Curtiss Electric constant-speed propeller through a 2:1 gear reduction. The V-1710-33 was 8 feet, 2.54 inches (2.503 meters) long, 3 feet, 5.88 inches (1.064 meters) high, and 2 feet, 5.29 inches (0.744 meters) wide. It weighed 1,340 pounds (607.8 kilograms).

Allison Engineering Co. V-1710-33 V-12 aircraft engine at the Smithsonian Institution National Air and Space Museum Steven F. Udvar-Hazy Center. (NASM)

The cruising speed of the P-40 was 272 miles per hour (438 kilometers per hour) and the maximum speed was 357 miles per hour (575 kilometers per hour) at 15,000 feet (4,572 meters). The Warhawk had a service ceiling of 30,600 feet (9,327 meters) and the absolute ceiling was 31,600 feet (9,632 meters). The range was 950 miles (1,529 kilometers) at 250 miles per hour (402 kilometers per hour).

Captain Charles W. Stark, Jr., 35th Pursuit Squadron, 8th Pursuit Group, climbing from the cockpit of a Curtiss-Wright P-40 Warhawk, 39-188, at Langley, Field, Virginia, 1941. Note the single .30-caliber machine gun visible on the left wing. (Rudy Arnold Collection/NASM)

The fighter (at the time, the Air Corps designated this type as a “pursuit”) was armed with two air-cooled Browning AN-M2 .50-caliber machine guns on the engine cowl, synchronized to fire through the propeller, with 380 rounds of ammunition per gun. Provisions were included for one Browning M2 .30-caliber aircraft machine gun, with 500 rounds of ammunition, in each wing.

The first production P-40 Warhawk, 39-156, made its first flight 4 April 1940. The 8th Pursuit Group at Langley Field, Virginia, was the first Army Air Corps unit to be equipped with the P-40.

Curtiss-Wright P-40 Warhawks of the 8th Pursuit Group at Langley Field, Virginia, 1940. (Unattributed)

After 200 P-40s were produced for the Air Corps, production was interrupted to allow Curtiss-Wright to build 100 Hawk 85A-1 export variants for the French Armée de l’air, then engaged with the invading forces of Nazi Germany. When France surrendered 22 June 1940, none of these airplanes had been delivered. The order was then assumed by the British Royal Air Force as the Tomahawk I.

U.S. Warhawk production resumed as the improved P-40B, and the remainder of the P-40 order was cancelled.

¹ Equivalent to $229,542,638.49 in 2018

© 2018, Bryan R. Swopes

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23 April 1941

North American Aviation Mustang Mk.I AG345, c/n 73-3098, prior to camouflage paint. Note the short carburetor air intake compared to the photograph of the camouflaged airplane, below. The RAF serial number, barely visible, is stenciled on the rudder just beneath the trim tab. (North American Aviation Inc. 73-0-6)

23 April 1941: At North American Aviation’s Inglewood, California factory, test pilot Louis Sanford Wait takes the very first production Mustang Mk.I, AG345, (c/n 73-3098) for its first flight.

The Royal Air Force had contracted with NAA to design and build a new fighter with a 1,200 horsepower Allison V-1710 supercharged 12-cylinder engine. The first order from the British Purchasing Commission was for 320 airplanes, and a second order for another 300 soon followed.

Mustang Mk.I AG345. (North American Aviation, Inc. 73-0-5)

The Mustang Mk.I (NAA Model NA-73) was a single-place, single-engine fighter primarily of metal construction with fabric control surfaces. It was 32 feet, 3 inches (9.830 meters) long with a wingspan of 37 feet, 5/16-inches (11.373 meters) and height of 12 feet, 2½ inches (3.721 meters). The airplane’s empty weight was 6,280 pounds (2,849 kilograms) and loaded weight was 8,400 pounds (3,810 kilograms).

North American Aviation Mustang Mk.I AG345 (North American Aviation Inc.)
North American Aviation Mustang Mk.I AG345 (North American Aviation Inc.)

The Mustang Mk.I was powered by a liquid-cooled, supercharged 1,710.597-cubic-inch-displacement (28.032 liter) Allison Engineering Company V-1710-F3R (V-1710-39) single overhead cam (SOHC) 60° V-12 engine with a compression ratio of 6.65:1. The -F3R had a Maximum Continuous Power rating of 880 horsepower at 2,600 r.p.m. at Sea level, and 1,000 horsepower at 11,000 feet (3,353 meters). It was rated at 1,150 horsepower at 3,000 r.p.m. for Take Off and Military Power. The Allison V-12 drove a 10 foot, 9 inch (3.277 meter) diameter, three-bladed Curtiss Electric constant-speed propeller through a 2.00:1 gear reduction. The V-1710-F3R was 7 feet, 4.38 inches (2.245 meters) long, 3 feet, 0.54 inches (0.928 meters) high, and 2 feet, 5.29 inches (0.734 meters) wide. It weighed 1,310 pounds (594 kilograms).

North American Aviation Mustang Mk.I AG345 (North American Aviation Inc.)

The Mustang Mk.I had a cruise speed of 311 miles per hour (500.5 kilometers per hour) at 75% power, and a maximum speed of 384 miles per hour (618 kilometers per hour) at 19,000 feet (5,791 meters). The airplane could reach 20,000 feet (6,096 meters) in 8.80 minutes. The service ceiling was 32,000 feet (9,754 meters) and its range was 640 miles (1,030 kilometers).

The Mk.I was equipped with four Browning AN-M2 .50-caliber machine guns, with one in each wing and two mounted in the nose under the engine. Four Browning .303 Mk.II machine guns were also installed, with two in each wing.

North American Aviation Mustang Mk.I AG345 (c/n 73-3098), front. (North American Aviation Inc.)
North American Aviation Mustang Mk.I AG345 (c/n 73-3098), front. (North American Aviation Inc.)

The Mk.I was 30 m.p.h. (48 kilometers per hour) faster than its contemporary, the Curtiss P-40 Warhawk, though both used the same engine. Below 15,000 feet (4,572 meters), the Mustang was also 30–35 m.p.h (48–56 kilometers per hour) faster than a Supermarine Spitfire, which had the more powerful Roll-Royce Merlin V-12.

Two Mustang Mk.Is, AG348 and AG354, were taken from the first RAF production order and sent to Wright Field for testing by the U.S. Army Air Force. These airplanes, assigned serial numbers 41-038 and 41-039, were designated XP-51. They would be developed into the legendary P-51 Mustang. In production from 1941 to 1945, a total of 16,766 Mustangs of all variants were built.

The first production Mustang Mk.I, AG345, first flight, 23 April 1941. (North American Aviation, Inc.)

Louis Sanford Wait was born 28 June 1908 at Superior, Nebraska. He was the first of two children of Dr. James Enos Wait, a dentist, and Alice Caroline Harrington Wait.

Wait enlisted in the Air Corps, United States Army, as an aviation cadet, in 1929. He trained as a pilot at March Field, near Riverside, California, and at Kelly Field, Bexar, Texas. Wait graduated 27 June 1930 and received his pilot’s wings and a commission as a second lieutenant, Air Corps Reserve. (O274973) Lieutenant Wait trained as an attack pilot and was assigned to Fort Crockett, Galveston, Texas.

From 1932 to 1935, Wait, having been released from active duty, was employed as a test pilot for the Boeing Airplane Company, Seattle, Washington.

By 1937, Lieutenant Wait was assigned to Headquarters Squadron, 2nd Bombardment Group at Langley Field, Virginia, under the command of Brigadier General Robert Olds. While on 18 days leave, on 3 December 1937, Second Lieutenant Wait married Mrs. Elsie O. Callow (née Elsie Oliver) at Amityville, New York.

Wait married Mrs. Mary Elizabeth Croxen (née Mary Elizabeth Musser), 2 November 1944, in Los Angeles, California.

In August 1946, Louis Wait entered a P-51C Mustang, NX28388, in the Bendix Trophy Race. The airplane had been purchased by Jackie Cochran. She flew it in the race and finished in second place behind Paul Mantz.

In 1951, Wait was appointed general administrator of a new North American Aviation plant at the Fresno Air Terminal, Fresno, California. The plant, which employed about 400 people, manufactured and repaired parts for the T-6/SNJ Texan flight trainers, and performed modifications to F-86 Sabre jet fighters.

Louis Sanford Wait died 3 July 1963, at the age of 55 years.

© 2019, Bryan R. Swopes

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4 April 1940

Chief test Pilot H. Lloyd Child (left, wearing goggles and flight suit) with a P-40 Warhawk. (LIFE Magazine)
Chief Test Pilot H. Lloyd Child (left, wearing goggles and flight suit) and Herbert O. Fisher, Chief Production Test Pilot, look at a Curtiss-Wright P-40 Warhawk. (Dmitri Kessel, LIFE Magazine)

4 April 1940: Curtiss-Wright’s Chief Test Pilot H. Lloyd Child took the first production P-40 Warhawk into the air for the first time at Buffalo, New York. The airplane carried the company serial number 13033, and had been assigned Air Corps serial number 39-156.

Curtiss P-40 Warhawk 39-156. (U.S. Air Force)

The Curtiss-Wright Corporation Hawk 81 (P-40 Warhawk) was a single-seat, single-engine pursuit. It was a low-wing monoplane with an enclosed cockpit and retractable landing gear (including the tail wheel). The airplane was of all-metal construction and used flush riveting to reduce aerodynamic drag. Extensive wind tunnel testing at the National Advisory Committee for Aeronautics (NACA) Langley Memorial Aeronautical Laboratory refined the airplane’s design, resulting in a significantly increased top speed.

Curtiss P-40 Warhawk 39-156. (U.S. Air Force)
Curtiss-Wright P-40 Warhawk 39-156. (U.S. Air Force)

The new fighter was 31 feet, 8-9/16 inches (9.666 meters) long with a wingspan of 37 feet, 3½ inches (11.366 meters) and overall height of 9 feet, 7 inches (2.921 meters). The P-40’s empty weight was 5,376 pounds (2,438.5 kilograms) and gross weight was 6,787 pounds (3,078.5 kilograms).

Curtiss Model 81, P-40 Warhawk 39-156. (San Diego Air & Space Museum Archive)

The P-40 was powered by a liquid-cooled, supercharged, 1,710.597-cubic-inch-displacement (28.032 liter) Allison Engineering Co. V-1710-C15 (V-1710-33), a single overhead cam (SOHC) 60° V-12 engine with a compression ratio of 6.65:1. The V-1710-33 had a continuous power rating of 930 horsepower at 2,600 r.p.m. at 12,800 feet (3,901 meters), and 1,040 horsepower at 2,800 r.p.m. for takeoff, burning 100-octane gasoline. It turned a three-bladed Curtiss Electric constant-speed propeller through a 2:1 gear reduction. The V-1710-33 was 8 feet, 2.54 inches (2.503 meters) long, 3 feet, 5.88 inches (1.064 meters) high, and 2 feet, 5.29 inches (0.744 meters) wide. It weighed 1,340 pounds (607.8 kilograms).

A 1939 Allison Engine Company V-1710-33 liquid-cooled, supercharged SOHC 60° V-12 aircraft engine at the Smithsonian Institution National Air and Space Museum. This engine weighs 1,340 pounds (607.8 kilograms) and produced 1,040 horsepower at 2,800 r.p.m. During World War II, this engine cost $19,000. (NASM)
Allison Engineering Co. V-1710-33 V-12 aircraft engine at the Smithsonian Institution National Air and Space Museum Steven F. Udvar-Hazy Center. (NASM)

The cruising speed of the P-40 was 272 miles per hour (438 kilometers per hour) and the maximum speed was 357 miles per hour (575 kilometers per hour) at 15,000 feet (4,572 meters). The Warhawk had a service ceiling of 30,600 feet (9,327 meters) and the absolute ceiling was 31,600 feet (9,632 meters). The range was 950 miles (1,529 kilometers) at 250 miles per hour (402 kilometers per hour).

Curtiss-Wright P-40 Warhawk 39-156.

The fighter (at the time, the Air Corps designated this type as a “pursuit”) was armed with two air-cooled Browning AN-M2.50-caliber machine guns on the engine cowl, synchronized to fire through the propeller arc, with 380 rounds of ammunition per gun. Provisions were included for one Browning M2 .30-caliber aircraft machine gun in each wing, with 500 rounds per gun.

Captain Charles W. Stark, Jr., 35th Pursuit Squadron, climbing from the cocpit of Curtis P-40 Warhawk 39-188, at Langley, Field, Virginia, 1941.
Captain Charles W. Stark, Jr., 35th Pursuit Squadron, 8th Pursuit Group, climbing from the cockpit of Curtis-Wright P-40 Warhawk 39-188, at Langley, Field, Virginia, 1941. (Rudy Arnold Collection/NASM))

On 26 April 1939, the U.S. Army Air Corps ordered 524 P-40 Warhawks, the largest single aircraft order up to that time. Only 200 of these aircraft were produced in the P-40 configuration. The Army deferred its order to allow Curtiss-Wright to produce Hawk 81A fighters for France, however that nation fell to enemy forces before any could be delivered. 140 of these French contract fighters were taken over by Britain’s Royal Air Force, which designated them as the Tomahawk Mk.I. Another 16 P-40s were delivered to the Soviet Air Force, having been purchased with gold.

A newly-built P-40 Warhawk is transported from the Buffalo, New York, assembly plant to the airfield, circa 1940. (Unattributed)

The 8th Pursuit Group at Langley Field, Virginia, was the first Army Air Corps unit to be equipped with the P-40.

Curtiss-Wright P-40 Warhawks of the 8th Pursuit Group at Langley Field, Virginia, 1940.

On 30 May 1942, P-40 39-156 was being flown by 2nd Lieutenant Leon Marcel Zele, 55th Fighter Squadron, 20th Fighter Group, based at Morris Field, North Carolina. At approximately 11:00 a.m., the P-40 crashed near Iron Station, North Carolina. Lieutenant Zele was killed when the airplane exploded.

Chief Test Pilot H. Lloyd Child in the cockpit of aCurtiss-Wright P-40 Warhawk, circa 1940. (Rudy Arnold Collection/NASM)

Henry Lloyd Child was born at Philadelphia, Pennsylvania, 25 May 1904, the second of two children of Edward Taggart Child, a consulting engineer in shipbuilding, and Lillian Rushmore Cornell Child. He was baptised at the Church of the  Good Shepherd, Rosemont, Pennsylvania, 22 December 1913. Child graduated from Flushing High School in Flushing, New York, then attended the Haverford School in Philadelphia.

“Skipper” Child majored in mechanical engineering at the University of Pennsylvania where he was a member of the Hexagon Senior Engineering Society and the Phi Sigma Kappa (ΦΣΚ) and Sigma Tau (ΣΤ) fraternities. He was a member of the varsity and all-state soccer team (left halfback), and also played football and tennis. Child graduated with a bachelor of science degree, 15 June 1926.

After graduation from college, Child went to work for the Curtiss-Wright Corporation as an engineer.

Child joined the United States Navy, 23 November 1927. He was trained as a pilot at Naval Air Station Hampton Roads, Norfolk, Virginia, and was commissioned as an Ensign. He was promoted to lieutenant (junior grade), 7 November 1932, and to lieutenant, 11 November 1935.

While maintaining his commission in the Navy, Child returned to Curtiss-Wright as a test pilot. He made the first flight of the P-36 Hawk.

Child became famous as the “World’s Fastest Human” when he put a Hawk 75A demonstrator into a vertical dive from 22,000 feet (6,706 meters) over Buffalo Airport, 24 January 1939. It was believed at the time that he had reached a speed in excess of 575 miles per hour (925 kilometers per hour). A contemporary news report said that the needle of the recording instrument had gone off the edge of the graph paper, and that the actual speed may have been faster than 600 miles per hour (966 kilometers per hour).

H. Lloyd Child worked for Lockheed from 1958 to 1968, when he retired. He died at Palmdale, California, 5 August 1970 at the age of 66 years.

H. Lloyd Child, Curtiss-Wright Corporation chief test pilot. (Test and Research Pilots, Flight Test Engineers)

© 2019, Bryan R. Swopes

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8 December 1945

The second prototype Douglas XB-42, 43-50225, In this photograph, the dual bubble canopies have been replaced with a single canopy to improve flight crew communication. (U.S. Air Force)
The second prototype Douglas XB-42, 43-50225, In this photograph, the dual bubble canopies have been replaced with a single canopy to improve flight crew communication. (U.S. Air Force)

8 December 1945: Lieutenant Colonel Henry E. Warden and Captain Glen W. Edwards, U.S. Army Air Corps, flew the second prototype Douglas XB-42, serial number 43-50225, from Long Beach, California to Washington, D.C., in 5 hours, 17 minutes, 34 seconds, averaging 433.6 miles per hour (697.8 kilometers per hour).

The XB-42 (originally designated as an attack aircraft, XA-42) was as unusual design. It used two engines inside the fuselage to drive counter-rotating three-bladed propellers in a pusher configuration at the tail. This created a very low-drag aircraft that was much faster than similar sized and powered aircraft.

Douglas XB-42 43-50225, the second prototype. (U.S. Air Force)
Douglas XB-42 43-50225, the second prototype. (U.S. Air Force)

A pilot and co-pilot sat side-by-side under separate bubble canopies. (This was later changed to improve communication between the crew.) The third crewman, a navigator/bombardier, occupied the nose. The co-pilot also served as a gunner and could operate four remotely-controlled .50-caliber machine guns located in two retractable power turrets inside the trailing edge of the wings. Another two .50-caliber machine guns were fixed, aimed forward. The bomber was designed to carry a 8,000 pound (3,629 kilogram) bomb load.

Douglas XB-42 43-50224 takes off from Palm Springs, California. (U.S. Air Force)

The XB-42 was powered several variants of the Allison Engineering Company E-series V-1710 engines, confiured as combined power assembles, and driving a remote propeller gear box through five Bell P-39 Airacobra driveshafts. The starboard engine turned counter-clockwise and drove the rear propeller. The port engine turned clockwise and drove the forward propeller. These engines were the V-1710-E23 (V-1710-103), V-1710-E24 (V -1710-125) and V-1710-E23B (V-1710-129). The V-1710 was a liquid-cooled, supercharged 1,710.60-cubic-inch-displacement (28.032 liter) single-overhead-camshaft (SOHC) 60° V-12 aircraft engine with four valves per cylinder. The engines used in the XB-42 had two-stage superchargers and turbosuperchargers.

The V-1710-129 was an experimental turbocompound engine, in which an exhaust-driven turbocharger is coupled to the drive shaft to provide a direct power input. It had a compression ratio of 6.65:1 and required 100/130 octane aviation gasoline. The V-1710-129 had a continuous power rating of 1,050 horsepower at 2,600 r.p.m., at Sea Level, and takeoff/military power rating of 1,675 horsepower at 3,200 r.p.m. (1,100 horsepower at 3,000 r.p.m. at 25,000 feet (7,620 meters) ). The engines turned three-bladed, counter-rotating, Curtiss Electric propellers through a 2.773:1 gear reduction. The forward propeller had a diameter of 13 feet, 2 inches (4.013 meters) and the rear diameter was 13 feet (3.962 meters). The difference was to prevent interference of the blade tip vortices.

Douglas XB-42 43-50224. (U.S. Air Force)
Douglas XB-42 43-50224. (U.S. Air Force)

The airplane was 53 feet, 8 inches long (16.358 meters), with a wingspan of 70 feet, 6 inches (21.488 meters). Empty weight was 20,888 pounds (9,475 kilograms), with a maximum gross weight of 35,702 pounds (16,194 kilograms). The prototype’s cruising speed was 310 miles per hour (499 kilometers per hour) and its maximum speed was 410 miles per hour (660 kilometers per hour) at 23,500 feet (7,163 meters). The service ceiling was 29,400 feet (8,961 meters). The XB-42’s normal range was 1,840 miles (2,961 kilometers).

Captain Glen W. Edwards, U.S. Air Force (1918–1948)
Captain Glen W. Edwards, U.S. Air Force (1918–1948)

Glen W. Edwards graduated from the University of California, Berkeley and soon after enlisted in the U.S. Army Air Corps. He was commissioned as a second lieutenant in February 1942 after completing flight training. Edwards flew 50 combat missions in the Douglas A-20 Havoc attack bomber during the North Africa and Sicily campaigns of World War II. He returned to the United States and was assigned to the Pilot Standardization Board, but was then sent to train as a test pilot at Wright Field. He tested the Northrop XB-35 flying wing and the Convair XB-46. He was recommended to fly the Bell X-1 rocket plane, but when that assignment went to Chuck Yeager, Edwards was sent to Princeton University, Princeton, New Jersey, to study aeronautical engineering.

Captain Edwards was killed along with four others while test flying the Northrop YB-49 “Flying Wing” in 1948. In 1949, Muroc Air Force Base, California, was renamed Edwards Air Force Base in his honor.

General Reuben C. Hood congratulates Captain Glen Edwards and Lieutenant Colonel Harold E. Warden after their record-setting transcontinental flight, 8 December 1945. ( © Bettman/CORBIS.)
(Left to right) Brigadier General Reuben C. Hood, Jr., congratulates Captain Glen W. Edwards and Lieutenant Colonel Harold E. Warden after their record-setting transcontinental flight, 8 December 1945. ( © Bettman/CORBIS.)

Colonel Henry E. (“Pete”) Warden (1915–2007) flew Curtiss P-40 Warhawks with the 20th Pursuit Squadron in the Philippine Islands at the beginning of World War II. He  was evacuated from Bataan to Australia, where he set up and ran the air logistics system for several years, before being sent to Wright Field.

After World War II, Warden was responsible for the development of the Convair B-36, Boeing B-47 and the Boeing B-52. He was called the “Father of the B-52.” After retiring from the Air Force, Colonel Warden went to work for North American Aviation on the B-70 Valkyrie program.

XB-42 43-50224 flew for the first time 1 August 1944. On 16 December 1945, it was on a routine flight from Bolling Field, Washington, D.C., with Lieutenant Colonel Fred J. Ascani in command, when a series of failures caused the crew to bail out. The XB-42 crashed at Oxon Hill, Maryland and was destroyed.

The second prototype, 43-50225, is in storage at the National Museum of the United States Air Force, Wright Patterson AFB, Ohio.

The first prototype XB-42, 43-50224, at Palm Springs, California, 1945. (U.S. Air Force)
The first prototype XB-42, 43-50224, at Palm Springs, California, 1945. (U.S. Air Force)

© 2016, Bryan R. Swopes

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