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18 December 1941

First Lieutenant Boyd D. Wagner, USAAC. (U.S. Air Force)
First Lieutenant Boyd David Wagner, United States Army Air Corps. (U.S. Air Force)

18 December 1941: First Lieutenant Boyd David (“Buzz”) Wagner, United States Army Air Corps, commanding officer of the 17th Pursuit Squadron (Interceptor) at Nichols Field, Pasay City, Commonwealth of the Philippines, shot down his fifth Japanese airplane, a Mitsubishi A6M2 Type Zero fighter, with his Curtiss-Wright P-40B Warhawk, near Vigan, Luzon. He became the first U.S. Army “ace” of World War II.

On 12 December 1941, “Buzz” Wagner was flying a lone reconnaissance mission over the airfield at Aparri, which had been captured by the invading Japanese. He was attacked by several Zero fighters but he evaded them, then returned and shot down two of them.  As he strafed the airfield he was attacked by more Zeros and shot down two more, bringing his score for the mission to four enemy airplanes shot down.

On 18 December, Lieutenant Wagner lead a flight of four P-40s to attack the enemy-held airfield at Vigan. He and Lieutenant Russell M. Church strafed and bombed the field while two other P-40s covered from overhead. Wagner destroyed nine Japanese aircraft on the ground, but as he passed over the field a Zero took off. Wagner rolled inverted to locate the Zero, then after spotting him, chopped his throttle and allowed the Zero to pass him. This left Wagner in a good position and he shot down his fifth enemy fighter. Lieutenant Church was shot down by ground fire and killed.

Mitsubishi A6M3 Model 22 "Zeke" in the Solomon Islands, 1943. (Imperial Japanese Navy)
A Mitsubishi A6M3 Navy Type 0 Model 22, UI 105, (Allied reporting name “Zeke”, but better known simply as “the Zero”) in the Solomon Islands, May 1943. This fighter is flown by Petty Officer 1st Class Hiroyoshi Nishizawa, 251st Kōkūtai, Imperial Japanese Navy Air Service. (Imperial Japanese Navy)

This fifth shoot down made Buzz Wagner the first U.S. Army Air Corps ace of World War II. He was awarded the Distinguished Service Cross, the Distinguished Flying Cross, and the Purple Heart for injuries sustained in an air battle, 22 December 1941. He was evacuated to Australia in January 1942.

2nd Lieutenant Boyd D. Wagner, Air Corps, United States Army.

Boyd David Wagner was born 26 October 1916 at Emeigh, Pennsylvania. He was the first of two children of Boyd Matthew Wagner, a laborer, and Elizabeth Moody Wagner. After graduating from high school, Wagner enrolled in the University of Pittsburgh, where he majored in aeronautical engineering.

After three years of college, Boyd Wagner enlisted as a flying cadet in the U.S. Army Air Corps, at Pittsburgh, Pennsylvania, 26 June 1937. He was commissioned as a Second Lieutenant, Air Corps Reserve, 16 June 1938. Lieutenant Wagner received advanced flight training and pursuit training, and on 1 October 1938 his commission as a reserve officer was changed to Second Lieutenant, Army Air Corps.

Wagner was promoted to First Lieutenant, Army of the United States, on 9 September 1940. Lieutenant Wagner was assigned to the 24th Pursuit Group in the Philippine Islands, 5 December 1940.

1st Lieutenant Boyd David Wagner, United States Army Air Corps, Philippine Islands, 1 December 1941. (Photograph by Carl Mydans/TIME & LIFE Pictures/Getty Images)
Lt. Col. Boyd D. Wagner

Lieutenant Wagner was promoted to the rank of Captain, A.U.S., 30 January 1942. On 11 April 1942, Captain Wagner was again promoted, bypassing the rank of Major, to Lieutenant Colonel, A.U.S. He was assigned to the 8th Fighter Group in New Guinea. On 30 April 1942, while flying a Bell P-39 Airacobra, Wagner shot down another three enemy airplanes. In September 1942, Colonel Wagner was sent back to the United States to train new fighter pilots.

On 29 November 1942, Colonel Wagner disappeared while on a routine flight from Eglin Field, Florida, to Maxwell Field, Alabama, in a Curtiss-Wright P-40K Warhawk, 42-10271. Six weeks later, the wreck of his fighter was found, approximately 4 miles north of Freeport, Florida. Lieutenant Colonel Boyd David Wagner, United States Army Air Corps, had been killed in the crash. His remains are buried at Grandview Cemetery, Johnstown, Pennsylvania.

Curtiss P-40B Warhawks at Clark Field, Philippine Islands, early December 1941.
Curtiss-Wright P-40B Warhawks of the 17th Pursuit Squadron, Nichols Field, Luzon, Philippine Islands, early December 1941. This squadron was under the command of 1st Lieutenant Buzz Wagner. (U.S. Air Force)

The Curtiss-Wright Corporation Hawk 81B (P-40B Warhawk) was a single-seat, single-engine pursuit. It 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. Extensive wind tunnel testing at the NACA Langley laboratories refined the airplane’s design, significantly increasing the top speed.

The P-40B Warhawk was 31 feet, 8¾ inches (9.671 meters) long, with a wingspan of 37 feet, 4 inches (11.379 meters) and overall height of 10 feet, 7 inches (3.226 meters). Its empty weight was 5,590 pounds (2,536 kilograms), and 7,326 pounds (3,323 kilograms) gross. The maximum takeoff weight was 7,600 pounds (3,447 kilograms).

Curtiss-Wright P-40B or C Warhawk, circa 1942. ¹ (Niagara Aerospace Museum)

The P-40B 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, which had a Continuous Power Rating of 930 horsepower at 2,600 r.p.m., from Sea Level to 12,800 feet (3,901 meters), and 1,150 horsepower at 3,000 r.p.m. to 14,300 feet  (4,359 meters) for Take Off and Military Power. The engine drove 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)
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)

Heavier than the initial production P-40, the P-40B was slightly slower, with a maximum speed of 352 miles per hour (567 kilometers per hour) at 15,000 feet (4,572 meters). It had a service ceiling of 32,400 feet (9,876 meters). Its range was 730 miles (1,175 kilometers).

Armament consisted of two air-cooled Browning AN-M2 .50-caliber machine guns mounted in the cowling and synchronized to fire forward through the propeller arc, with 380 rounds of ammunition per gun, and four Browning AN-M2 .30-caliber aircraft machine guns, with two in each wing.

Curtiss-Wright produced 13,738 P-40s between 1939 and 1944. 131 of those were P-40B Warhawks.

These Curtiss P-40B Warhawks of the 44th Pursuit Squadron, 18th Pursuit Group, are the same type aircraft flown by Buzz Wagner. (U.S. Air Force)
These Curtiss P-40B Warhawks of the 44th Pursuit Squadron, 18th Pursuit Group, are the same type aircraft flown by Buzz Wagner in combat over the Philippine Islands. (U.S. Air Force)

¹ The Warhawk in the photograph may be P-40C 41-13471, s/n 16351.

© 2018, Bryan R. Swopes

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17 December 1944

Major Richard Ira Bong, Air Corps, United States Army, Leyte, 12 December 1944. Major Bong is wearing the Medal of Honor. (U.S. Air Force)

17 December 1944: Major Richard Ira Bong, United States Army Air Corps, flying a Lockheed P-38 Lighting over San José on the Island of Mindoro, Commonwealth of the Philippines, shot down an enemy Nakajima Ki-43 Hayabusa (Allied reporting name, “Oscar”).

This was Bong’s 40th confirmed aerial victory and made him the leading American fighter ace of World War II. He is officially credited with 40 aircraft destroyed, 8 probably destroyed and 7 damaged.

Five days earlier, 12 December, during a ceremony at an American airfield on the Island of Leyte, Philippine Islands, General Douglas MacArthur, United States Army, had presented Major Bong the Medal of Honor.

An Associated Press reporter quoted the General:

“Of all military attributes, that one which arouses the greatest admiration is courage. It is the basis of all successful military ventures. our forces possess it to a high degree and various awards are provided to show the public’s appreciation. The Congress of the United States has reserved to itself the honor of decorating those amongst all who stand out as the bravest of the brave. It’s this high and noble category, Bong, that you now enter as I pin upon your tunic the Medal of Honor. Wear it as a symbol of the invincible courage you have displayed so often in mortal combat. My dear boy, may a merciful God continue to protect you is the constant prayer of your commander in chief.”

[On 18 December 1944, Douglas MacArthur was promoted to General of the Army, a five-star rank held by only nine other U.S. military officers. General MacArthur was the son of a Medal of Honor recipient, and had himself been twice nominated for the Medal for his actions during the occupation of Vera Cruz (1914) and the Meuse-Argonne Offensive (1918). He was awarded the Medal of Honor for his defense of the Philippines, 1941–42.]

General Douglas MacArthur talks with Major Richard I. Bong, 12 December 1944. (U.S. Air Force)
General Douglas MacArthur talks with Major Richard I. Bong, Leyte, Philippine Islands, 12 December 1944. (U.S. Air Force)

Richard Bong’s citation reads:

MEDAL OF HONOR

The President of the United States of America, in the name of Congress, takes pleasure in presenting the Medal of Honor to Major (Air Corps) Richard Ira Bong, United States Army Air Forces, for conspicuous gallantry and intrepidity in action above and beyond the call of duty while serving with the 49th Fighter Group, V Fighter Command, Fifth Air Force, in action in the Southwest Pacific area from 10 October to 15 November 1944.

Though assigned to duty as gunnery instructor and neither required nor expected to perform combat duty, Major Bong voluntarily and at his own urgent request engaged in repeated combat missions, including unusually hazardous sorties over Balikpapan, Borneo, and in the Leyte area of the Philippines. His aggressiveness and daring resulted in his shooting down eight enemy airplanes during this period.

General Orders: War Department, General Orders No. 90, December 8, 1944
Action Date: October 10 – November 15, 1944
Service: Army Air Forces
Rank: Major
Regiment: 49th Fighter Group, V Fighter Command
Division: 5th Air Force.

Dick Bong poses with "Marge," his Lockheed P-38J Lightning. A large photograph of his fiancee, Miss Marjorie Vattendahl, is glued to the fighter's nose.
Dick Bong poses with “Marge,” his Lockheed P-38J-15-LO Lightning, 42-103993, Lockheed serial number 2827. A large photograph of his fiancée, Miss Marjorie Ann Vattendahl, is affixed to the fighter’s nose.

Major Bong flew a number of different Lockheed P-38s in combat. He is most associated, though, with P-38J-15-LO 42-103993, which he named Marge after his fiancée, Miss Marjorie Ann Vattendahl, a school teacher from Poplar, Wisconsin.

Richard Bong had flown 146 combat missions. General George C. Kenney, commanding the Far East Air Forces, relieved him from combat and ordered that he return to the United States. He was assigned to test new production P-80 Shooting Stars jet fighters being built at Lockheed Aircraft Corporation’s Burbank, California plant.

On 6 August 1945, the fuel pump of the new P-80 Bong was flying failed just after takeoff. The engine failed from fuel starvation and the airplane crashed into a residential area of North Hollywood, California. Major Richard Ira Bong was killed.

Nakajima Ki-43 Type 1 Army Fighter (AvionsLegendaires.net)

The Nakajima Ki-43 Type 1 Hayabusa was a single-place, single-engine fighter manufactured by Nakajima Hikoki K.K. for the Imperial Japanese Army Air Service. The light weight fighter was very maneuverable and was a deadly opponent. It was identified as “Oscar” by Allied forces. The Ki-43 shot down more Allied airplanes during World War II than any other Japanese fighter.

The Ki-43 was 29.2 feet (8.90 meters) long, with a wingspan of 35.6 feet (10.85 meters) and height of 9 feet (2.74 meters). Its empty weight was 4,170 pounds (1,878 kilograms) and gross weight  was 5,500 pounds (2,495 kilograms).

The Ki-43 Type 1 Army Fighter was powered by an air-cooled, supercharged Nakajima Ha-115 Toku two-row, 14-cylinder radial engine which produced 925 horsepower at 9,350 feet (2,850 meters), 800 horsepower  at 20,000 feet (6,096 meters), and 1,105 horsepower at Sea Level for takeoff. The engine drove a three-bladed constant-speed propeller with a diameter of 9.2 feet (2.80 meters).

Nakajima Ki-43 Type 1 Army Fighter, called “Oscar” by the Allied forces. (The Java Gold’s Blog)

Compared to American fighters, the Oscar was lightly armed with just two synchronized 7.7 mm × 58 mm Type 89 or 12.7 mm × 81 mm Type 1 machine guns, or a combination of one 7.7 mm and one 12.7 mm gun. The 12.7 machine gun could fire explosive ammunition. (The Type 89 was a licensed version of the Vickers .303-caliber machine gun, while the design of the Type 1 was based on the Browning M1921 .50-caliber machine gun.)

The Oscar’s maximum speed was 295 miles per hour (475 kilometers per hour) at Sea Level, and 347 miles per hour (558 kilometers per hour) at 20,000 feet (6,096 meters). Its service ceiling was 37,100 feet (11,308 meters). The maximum range with a normal fuel load of 149 U.S. gallons (564 liters) was 1,180 miles (1,899 kilometers) at 1,500 feet (457 meters).

Lockheed P-38J-10-LO Lightning 42-68008, Lockheed serial number 2519. (Lockheed Martin)

The Lockheed P-38 lightning is a single-place, mid-wing, twin-engine fighter. It is an unusual configuration, with the cockpit, weapons and nose landing gear in a central nacelle, and engines, turbochargers, cooling system and main landing gear in outer “booms.” The airplane was originally designed by Clarence L. “Kelly” Johnson.

The P-38J is 37 feet, 10 inches (11.532 meters) long, with a wingspan of 52 feet, 0 inches (15.850 meters) and overall height of 9 feet, 9-11/16 inches (2.989 meters). The fighter has an empty weight of 12,700 pounds (5,761 kilograms) and maximum gross weight of 21,600 pounds (9,798 kilograms).

The P-38J was powered by two liquid-cooled, turbosupercharged 1,710.597-cubic-inch displacement (28.032 liter) Allison Engineering Company V-1710-F-17R and -F17L (V-1710-89 and -91, respectively) single overhead cam (SOHC) 60° V-12 engines with a continuous power rating of 1,100 horsepower at 2,600 r,p.m., to 30,000 feet (9,144 meters), and a takeoff/military power rating of 1,425 horsepower at 3,000 r.p.m. The counter-rotating engines drove 11 feet, 6 inches (3.505 meters) diameter, three-bladed Curtiss Electric full-feathering constant-speed propellers through a 2.00:1 gear reduction. The engines were 7 feet, 1.34 inches (2.168 meters) long, 3 feet, 0.75 inches (0.933 meters) high, 2 feet, 5.28 inches (0.744 meters) wide, and weighed 1,350 pounds (612 kilograms).

A flight of two camouflaged Lockheed P-38J Lightnings, circa 1943. Dick Bong is flying the closer airplane, P-38J-5-LO 42-67183. (Lockheed Martin)

The P-38J had a maximum speed of 420 miles per hour (676 kilometers per hour) at 26,500 feet (8,077 meters). The service ceiling was 44,000 feet (13,411 meters). Carrying external fuel tanks, the Lightning had a maximum range of 2,260 miles (3,637 kilometers).

P-38s were armed with one 20 mm Hispano M2 aircraft autocannon with 150 rounds of ammunition, and four air-cooled Browning AN-M2 .50-caliber machine guns with 500 rounds per gun. All guns are grouped close together in the nose and aimed straight ahead.

A Lockheed P-38 Lighning test fires its guns. (Lockheed Martin)

Between 1939 and 1945, Lockheed Aircraft Corporation built 10,037 P-38 Lightnings at Burbank, California. 2,970 of these were P-38Js.

Major Richard Ira Bong, Air Corps, United States Army. (Richard I. Bong Veterans Historical Center/National Endowment for the Humanities)

© 2018, Bryan R. Swopes

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4 November 1941

Lockheed YP-38 Lightning 39-689, manufacturer's serial number 122-2202. (Lockheed)
Lockheed YP-38 Lightning 39-689, manufacturer’s serial number 122-2202. (Lockheed Martin)
Ralph Burwell. Virden (Los Angeles Times)

4 November 1941: Lockheed test pilot Ralph Burwell Virden was conducting high speed dive tests in the first Lockheed YP-38 Lightning, Air Corps serial number 39-689 (Lockheed’s serial number 122-2202).

As the airplane’s speed increased, it approached what is now known as its Critical Mach Number. Air flowing across the wings accelerated to transonic speeds and began to form shock waves. This interrupted lift and caused a portion of the wing to stall. Air no longer flowed smoothly along the airplane and the tail surfaces became ineffective. The YP-38 pitched down into a steeper dive and its speed increased even more.

Designed by famed aeronautical engineer Clarence L. “Kelly” Johnson, the YP-38 had servo tabs on the elevator that were intended to help the pilot maintain or regain control under these conditions. But they increased the elevator’s effectiveness too well.

The Los Angeles Times described the accident:

      Witnesses said the twin-engined, double-fuselaged ship was booming westward at near maximum speed (unofficially reported to be between 400 and 500 miles an hour) when the duralumin tail assembly “simply floated away.”

     A moment afterward the seven-ton craft seemed to put on a burst of speed, the the high whine of its engines rising.

     It then went into a downward glide to about 1500 feet, then into a flat spin, flipped over on its back and shot earthward.

     Several persons said that they thought they had heard an explosion during the dive, but qualified observers doubted it. . .

     . . . Fellow pilots at Lockheed said, “Ralph was the best we had, especially in power dives.”

      Robert E. Gross, president of Lockheed, said, “Ralph Virden was a great pilot but an even greater man. If anyone ever had national defense at heart it was he, who every day was carrying the science of aviation into new and higher fields.”

     Various witnesses said the ill-fated ship’s tail assembly could be followed easily as its bright surfaces glinted in the sun during its drop to earth. It landed several blocks from the scene of the crash.

     Mrs. Jack Davenport of 1334 Elm Ave., left her ironing board when she heard the unfamiliar roar of the plunging plane’s engines.

     “I ran out and saw it passing over us, very low. It disappeared among the trees and then zoomed back into sight just before crashing in the next block,” she said. “It looked just like a toy airplane. I knew the pilot didn’t have a chance, as the ship was too low and going too fast.”

Los Angeles Times, Vol. LX, Wednesday, 5 November 1941, Page 1, Column 6, and Page 2, Column 5.

The YP-38 crashed into the kitchen of Jack Jensen’s home at 1147 Elm Street, Glendale, California. Fire erupted. Ralph Virden was killed. The airplane’s tail section was located several blocks away.

Another view of Lockheed YP-38 Lightning 39-689. It's factory serial number, "2202," is stenciled on the nose. (Lockheed Martin)
Another photograph of Lockheed YP-38 Lightning 39-689. The factory serial number, “2202,” is stenciled on the nose. (Lockheed Martin)

39-689 was the first of thirteen YP-38 service test aircraft that had been ordered by the U.S. Army Air Corps shortly after the XP-38 prototype, 37-457, had crashed on a transcontinental speed record attempt, 11 February 1939. 39-689 made its first flight 16 September 1940 with test pilot Marshall Headle at the controls. With hundreds of production P-38s being built, Lockheed continued to use the YP-38 for testing.

Newspaper phototograph of the wreckage of Lockheed YP-38 Lightning 39-689 at 1147 Elm Street, Glendale, California. (Los Angeles Times)
Newspaper photograph of the wreckage of Lockheed YP-38 Lightning 39-689 at 1147 Elm Street, Glendale, California. (Los Angeles Times)

The YP-38s were service test prototypes of a single-place, twin engine long range fighter with a unique configuration. There was not a fuselage in the normal sense. The cockpit, nose landing gear, and armament were contained in a central nacelle mounted to the wing. Two engines and their turbochargers, cooling systems and main landing gear were in two parallel booms. The booms end with vertical fins and rudders, with the horizontal stabilizer and elevator between them. The P-38 was 37 feet, 9–15/16 inches (11.530 meters) long, with a wingspan of 52 feet, 0 inches (15.850 meters) and height of 12 feet, 10 inches (3.952 meters).

The P-38’s wings had a total area of 327.50 square feet (30.43 square meters). Their angle of incidence was 2° and there was 5° 40′ dihedral. The leading edges were swept aft 5° 10′.

The YP-38 had an empty weight 11,171 pounds (5,067 kilograms). The gross weight was 13,500 pounds (6,123 kilograms) and the maximum takeoff weight 14,348 pounds (6,508 kilograms).

The YP-38 was powered by two counter-rotating, liquid-cooled, turbosupercharged 1,710.597-cubic-inch displacement (28.032 liter) Allison V-1710-27 right-hand tractor and V-1710-29 left-hand tractor, single overhead cam (SOHC) 60° V-12 engines (Allison Engineering Co. Models F2R and F2L) with a Normal Power rating of 1,000 horsepower at 2,600 r.p.m., and 1,150 horsepower at 3,000 r.p.m. for takeoff. They drove three-bladed Curtiss Electric constant-speed propellers with a diameter of 11 feet, 6 inches (3.505 meters) through a 2.00:1 gear reduction. In a change from the XP-38, the propellers rotated outboard at the top of their arc. The V-1710-27/-29 engines were 7 feet, 1-5/8 inches (2.175 meters) long, 2 feet, 5-9/32 inches (0.744 meters) wide and 3 feet, 0-17/32 inches (0.928 meters) high. The V-1710-27/-29 weighed 1,305 pounds (592 kilograms)

The YP-38 had a maximum speed of 405 miles per hour (651.8 kilometers per hour) at 10,000 feet (3,048 meters) and it could climb  from the surface to 20,000 feet (6,096 meters) in six minutes. Normal range 650 miles (1,046 kilometers).

Lockheed built one XP-38, thirteen YP-38s, and more than 10,000 production fighter and reconnaissance airplanes. At the end of World War II, orders for nearly 2,000 more P-38 Lightnings were cancelled.

Lockheed YP-38 39-692 in flight.(Hans Groenhoff Photographic Collection, Smithsonian Institution National Air and Space Museum NASM-HGC-967)

Ralph Burwell Virden was born 11 June 1898, at Audobon Township, Illinois. He was the second child of Hiram R. Virden, a farmer, and Nancy Carrie Ivy Virden.

Virden attended Bradley Polytechnic Institute at Peoria, Illinois. At the age of 17, 15 October 1918, Ralph Virden enlisted in the U.S. Army. With the end of World War I less than one month later, he was quickly discharged, 7 December 1918.

In 1919, Ralph Virden married Miss Florence I. McCullers. They would have two children, Kathryn and Ralph, Jr. Kathryn died in 1930 at the age of ten years.

Ralph Burwell Virden with a Boeing Model 40 mail plane, circa late 1920s. As a U.S. Air Mail pilot, Virden is armed with a .45-caliber Colt M1911 semi-automatic pistol. (San Diego Air and Space Museum Archives)
Boeing Airplane Company President Clairmont L. Egvtedt and United Air Lines Captain Ralph B. Virden examine a scale model of the Boeing 247D airliner. (Boeing)

During the mid-1920s, Virden flew as a contract mail pilot. He held Airline Transport Pilot Certificate No. 628, and was employed by Gilmore Aviation and Pacific Air Transport. For thirteen years, Virden was a pilot for United Air Lines. He joined Lockheed Aircraft Company as a test pilot in 1939. He had flown more than 15,000 hours.

Virden lived at 4511 Ben Ave., North Hollywood, California, with his  family. Ralph, Jr., now 19 years of age, was also employed at Lockheed. (Following his father’s death, the younger Virden enlisted in the United States Navy.)

After the accident, Lockheed, the Air Corps and the National Advisory Committee on Aeronautics (NACA) undertook an extensive test program of the P-38.

The Lockheed YP-38 Lightning, 39-690, was sent to the NACA Research Center at Langley Field, Virginia. This photograph is dated 4 February 1942. (NASA)
The second Lockheed YP-38 Lightning, 39-690, was sent to the NACA Langley Research Center at Langley Field, Virginia. This photograph is dated 4 February 1942. (NASA)
Lockheed YP-38 39-690 in the NACA Full Scale Tunnel, December 1944. (NASA)
Lockheed YP-38 39-690 in the NACA Full Scale Tunnel, December 1944. (NASA)
Lockheed YP-38 Lightning 39-690, serial number 122-2203. (NASA)
Lockheed YP-38 Lightning 39-690, serial number 122-2203. (NASA)
Lockheed YP-38 #2 in the NACA full-scale wind tunnel at Langley, Virginia. (NASA)
Lockheed YP-38 Lightning, 39-690 (122-2203), in the NACA Langley Research Center’s full-scale wind tunnel at Langley Field, Virginia, December 1944. (NASA)
Lockheed YP-38 Lightning 39-690. (NASA)
Lockheed YP-38 Lightning 39-690. (NASA)
Lockheed YP-38 Lightning 39-690. (NASA)
Lockheed YP-38 Lightning 39-690. (NASA)
Lockheed YP-38 Lightning 39-690. (NASA)
Lockheed YP-38 Lightning 39-690. (NASA)
Lockheed YP-38 Lightning 39-690, 122-2203. (NASA)
Lockheed YP-38 Lightning 39-690, 122-2203. (NASA)

© 2018, Bryan R. Swopes

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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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6 May 1941

Republic XP-47B 40-3051 prototype in flight. (Republic Aircraft Corporation)

6 May 1941: Just eight months after a prototype for a new single-engine fighter was ordered by the U.S. Army Air Forces, test pilot Lowery Lawson Brabham took off from the Republic Aviation Corporation factory airfield at Farmingdale, New York, and flew the prototype XP-47B Thunderbolt, serial number 40-3051, to Mitchel Field, New York.

During the flight, oil which had collected in the exhaust duct began burning. There was so much smoke that Brabham considered bailing out. He stayed with the prototype, though, and when he arrived at Mitchel Field, he exclaimed, “I think we’ve hit the jackpot!”

Alexander Kartveli

The prototype was designed by Alexander Kartveli, a Georgian immigrant and former chief engineer for the Seversky Aircraft Corporation, which became the Republic Aviation Corporation in 1939.

Alexander Kartveli (née Kartvelishvili, ალექსანდრე ქართველი) was born in Tbilisi, in the Kutais Governorate of the Russian Empire, (what is now, Georgia). After World War I, during which he was wounded, Kartvelishvili was sent to study at the Paris Aviation Higher College of Engineering in France by the government of the Democratic Republic of Georgia. He graduated in 1922. Kartvelishvili did not return to his country, which had fallen to the Red Army in the Soviet-Georgian War. He worked for Blériot Aéronautique S.A. until 1928, when he was employed by the Fokker American Company (also known as Atlantic Aircraft, or Atlantic-Fokker) which was headquartered at Passaic, New Jersey, in the United States. In 1931, he became chief engineer for the Seversky Aircraft Company in Farmingdale.

Republic XP-47B Thunderbolt prototype 40-3051 at Farmingdale, New York, 1941. The pilot standing in front of the airplane gives a scale reference. (Republic Aviation Corporation)

The XP-47B was the largest single-engine fighter that had yet been built. The production P-47B was 34 feet, 10 inches (10.617 meters) long with a wingspan of 40 feet, 9-5/16 inches (12.429 meters), and height of 12 feet, 8 inches (3.861 meters).¹ The wing area was 300 square feet (27.9 square meters). At a gross weight of 12,086 pounds (5,482 kilograms), it was nearly twice as heavy as any of its contemporaries.

Republic XP-47B Thunderbolt 40-3051 at Wright Field, Dayton, Ohio.(Ray Wagner Collection, San Diego Air & Space Museum Archives )

The XP-47B was powered by an air-cooled, supercharged and turbocharged, 2,804.4-cubic-inch-displacement (45.956 liter) Pratt & Whitney R-2800-21 (Double Wasp TSB1-G) two-row, 18-cylinder radial with a compression ratio of 6.65:1 had a normal power rating of 1,625 horsepower at 2,550 r.p.m., to an altitude of 25,000 feet (7,620 meters), and a takeoff/military power rating of 2,000 horsepower at 2,700 r.p.m. at 25,000 feet (7,620 meters). The engine drove a 12-foot, 2 inch (3.708 meter) diameter, four-bladed Curtiss Electric constant-speed propeller through a 2:1 gear reduction. The R-2800-21 was 4 feet, 4.50 inches (1.340 meters) in diameter and 6 feet, 3.72 inches (1.923 meters) long. The engine weighed 2,265 pounds (1,027 kilograms). Approximately 80% of these engines were produced by the Ford Motor Company. It was also used as a commercial aircraft engine, with optional propeller gear reduction ratios.

A large General Electric turbosupercharger was mounted in the rear of the fuselage. Internal ducts carried exhaust gases from the engine to drive the turbocharger. This supercharged air was then carried forward through an intercooler and then on to the carburetor to supply the engine. The engine’s mechanical supercharger further pressurized the air-fuel charge.

Republic XP-47B 40-3051. The pilot enters the cockpit through a hinged canopy segment. (Ray Wagner Collection Catalog, San Diego Air and Space Museum)

During flight testing, the XP-47B Thunderbolt demonstrated speeds of 344.5 miles per hour (554.4 kilometers per hour) at 5,425 feet (1,654 meters), and 382 miles per hour (615 kilometers per hour) at 15,600 feet (4,745 meters). Its maximum speed was 412 miles per hour (663 kilometers per hour) at 25,800 feet (7,864 meters). The test pilot reported that the engine was unable to produce full power during these tests. It was determined that it had a cracked cylinder head, resulting in a loss of 2.5–4% of its maximum rated power. Also, the XP-47B was painted in camouflage, resulting in a slight loss of speed.

It could climb to 15,000 feet (4,572 meters) in just five minutes.

The Thunderbolt was armed with eight Browning AN-M2 .50-caliber machine guns, four in each wing, with 3,400 rounds of ammunition. It could also carry external fuel tanks, rockets and bombs. The structure of the P-47 could be described as “robust” and it was heavily armored. The amount of damage that the airplane could absorb and still return was remarkable.

 

Republic XP-47B Thunderbolt 40-3051, 4 May 1941. (U.S. Air Force)
Republic XP-47B Thunderbolt 40-3051, 4 May 1941. (Republic Aviation Corporation)

During a test flight, 4 August 1942, the XP-47B’s tail wheel was left down. The extreme heat of the turbocharger’s exhaust set fire to the tire, which then spread to the airplane’s fabric-covered control surfaces. Unable to control the airplane, test pilot Filmore L. Gilmer bailed out. The prototype Thunderbolt crashed into Long Island Sound and was destroyed.

The third production Republic P-47B Thunderbolt, 41-5897, at Langley Field, Virginia, 24 March 1942. The door-hinged canopy of the XP-47B has been replaced by a rearward-sliding canopy, requiring that the radio antenna mast be moved.(NASA)
A Republic P-47B Thunderbolt in the NACA Full Scale Tunnel, 31 July 1942. (NASA LMAL 29051)

A total of 15,683 Thunderbolts were built; more than any other Allied fighter type. In aerial combat, it had a kill-to-loss ratio of 4.6:1. The P-47, though, really made its name as a ground attack fighter, destroying aircraft, locomotives, rail cars, and tanks by the many thousands. It was one of the most successful aircraft of World War II.

¹ Data from Pilot’s Flight Operating Instructions, Technical Order No. 01-65BC-1, 20 January 1943

© 2018, Bryan R. Swopes

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