25 November 1940: De Havilland Aircraft Company’s Chief Test Pilot, Geoffrey Roal de Havilland, Jr., and engineer John Walker, made the first flight of the DH.98 Mosquito prototype, E0234, at Hatfield, Hertfordshire, England. The multi-role combat aircraft was constructed primarily of layers of balsa covered with layers of birch, then a layer of doped cotton fabric. It was powered by two Rolls-Royce Merlin V-12 engines.
The construction materials took advantage of plentiful supplies of wood, and also made workers who were not in the standard metal aircraft industry able to take part.
The prototype was rolled out 19 November 1040, painted overall yellow.
The prototype had a wingspan of 54 feet, 2 inches (16.510 meters), and its gross weight was 19,670 pounds (8,922 kilograms). W4050 was powered by two liquid-cooled, supercharged, 1,648.96-cubic-inch-displacement (27.01 liter) Rolls-Royce Merlin Mk.21 single overhead camshaft (SOHC) 60° V-12 engines, producing 1,460 horsepower at 3,000 r.p.m. at 10,000 feet (3028 meters), with 10 pounds (0.69 Bar) of boost, and driving three-bladed de Havilland Hydromatic propellers through a gear reduction.
The DH.98 had been predicted to be 20 miles per hour (32 kilometers per hour) faster than the Supermarine Spitfire, but was actually much faster. In testing, the prototype reached 392 miles per hour (631 kilometers per hour) at 22,000 feet (6,706 meters). Improvements were continuously made, and with 2-stage superchargers, W4050 reached a maximum 437 miles per hour (703 kilometers per hour). The DH.98 prototype had a service ceiling of 34,000 feet (10,363 meters) and range of 2,180 miles (3,500 kilometers).
The production fighter variant, the Mosquito F. Mk.II, was 41 feet, 2 inches (12.548 meters) long with a wingspan of 54 feet, 2 inches (16.510 meters) and height of 15 feet, 3 inches (4.648 meters) in 3-point position. The wings had 1½° incidence with approxmatey 2½° dihedral. The leading edges were swept aft 2½°. The total wing area was 436.7 square feet (40.6 square meters). The fighter’s empty weight was 13,356 pounds (6,058 kilograms) and the maximum takeoff weight was 18,649 pounds (8,459 kilograms).
The Mk.II had a cruise speed of 265 miles per hour (426 kilometers per hour) at 15,000 feet (4,572 meters) and maximum speed of 380 miles per hour (612 kilometers per hour) at 21,400 feet (6,523 meters).
Mosquito bomber variants could carry four 500 pound bombs, or two 2,000 pound bombs, but were otherwise unarmed. Fighters were equipped with four Hispano Mk.II 20 mm autocannon and four Browning .303-caliber Mk.II machine guns in the nose.
6,411 DH.98 Mosquitoes were built in England, 1,134 in Canada and 212 in Australia. It was produced in bomber, fighter, night fighter, fighter bomber and photo reconnaissance versions.
W4050’s (the prototype’s Royal Air Force identification) fuselage was damaged while taxiing at Boscombe Down, 24 February 1941, and had to be replaced with one intended for a second prototype, W4051. It remained at de Havilland and was used to test different engines, armaments and versions. After a series of tests conducted in December 1943, the prototype Mosquito was permanently grounded. It was used as an instructional airframe and later placed in storage.
In September 1958, W4050 was turned over to the de Havilland Aircraft Heritage Centre. Today, the restored prototype DH.98 Mosquito is at the museum at London Colney, Hertfordshire, England.
6 November 1935: The prototype Hawker Monoplane F.36/34, K5083, first flew at the Brooklands Aerodrome, Weybridge, Surrey, with Hawker’s Chief Test Pilot, Flight Lieutenant Paul Ward Spencer (“George”) Bulman, M.C., A.F.C., Royal Air Force Reserve,¹ in the cockpit. The airplane would be named “Hurricane” and become one of the most successful fighter aircraft of World War II.
Designed by Sydney Camm to meet a Royal Air Force Specification for a high speed monoplane interceptor, the airplane was developed around the Rolls-Royce PV-12 engine.
The Hurricane was built in the traditional means of a light but strong framework covered by doped linen fabric. Rather than wood, however, the Hurricane’s framework used high strength steel tubing for the aft fuselage. A girder structure covered in sheet metal made up the forward fuselage. A primary consideration of the fighter’s designer was to provide good visibility for the pilot. The cockpit sits high in the fuselage and gives the airplane its characteristic hump back profile. The cockpit was enclosed by a sliding canopy. The landing gear was retractable.
The Rolls-Royce PV-12 (“PV” stood for Private Venture) was a developmental liquid-cooled 1,649-cubic-inch-displacement (27.022 liter) 60° V-12 that would become the legendary Merlin aircraft engine. The PV-12 first ran in 1933 and initially produced 700 horsepower.
The engine was progressively improved and by the time the Hurricane prototype first flew, it was equipped with a supercharged Rolls-Royce Merlin C, Air Ministry serial number 111144. The Merlin C had a Normal Power rating of 1,029 horsepower at 2,600 r.p.m, at an altitude of 11,000 feet (3,353 meters), with +6 pounds per square inch boost. The V-12 engine turned a Watts two-bladed fixed-pitch wooden propeller through a gear reduction drive (possibly 0.420:1).
An Aeroplane and Armament Experimental Establishment (A&AEE) test pilot, Flight Sergeant Samuel (“Sammy”) Wroath (366485), flew K5083 at the Martlesham Heath in early 1936. He wrote, “The aircraft is simple to fly and has no apparent vices.”
In early flight testing, K5083 had a maximum speed of 253 miles per hour (407 kilometers per hour) at Sea Level, an reached 315 miles per hour (507 kilometers per hour) at 16,200 feet (4,938 meters), with the Merlin turning 2,960 r.p.m., with +5.7 pounds of boost (0.39 Bar). The speed exceeded the RAF’s requirement by 5 miles per hour (8 kilometers per hour).
The prototype was able to take off in as little as 795 feet (242 meters) and to climb to 15,000 feet (4,572 meters) in just 5 minutes, 42 seconds. It reached 20,000 feet (6,096 meters) in 8 minutes, 24 seconds. The peak altitude reached was 30,000 feet (9,144 meters). The prototype’s estimated service ceiling was 34,500 feet (10,516 meters)and the estimated absolute ceiling was 35,400 feet (10,790 meters).
In May 1939 Hawker Monoplane F.36/34 K5083 was classified as a ground instruction airframe, with serial number 1112M. Reportedly, it remained in airworthy condition until 1942. Its status after that is not known.
The Hawker Hurricane Mk.I was ordered into production in the summer of 1936. The first production airplane, L1547, flew on 12 October 1937. The Hurricane Mk. I retained the wooden fixed-pitch propeller and fabric-covered wings of the prototype, though this would change with subsequent models.
The Hurricane Mk.I was 31 feet, 5 inches (9.576 meters) long with a wingspan of 40 feet, 0 inches (12.192 meters), and overall height of 13 feet, 3 inches (4.039 meters) in three-point attitude. The wings had a total area of 257.6 square feet (23.9 square meters). Their angle of incidence was 2° 0′, and the outer wing panels had 3° 30′ dihedral. The leading edges were swept aft 5° 6′. The empty weight of the Hurricane I was 5,234 pounds (2,374 kilograms) and maximum gross weight was 6,793 pounds (3,081 kilograms).
The Hurricane Mk.I was powered by a Rolls-Royce Merlin Mk.II or Mk.III. The Mk.III was rated at 1,030 horsepower at 3,000 r.p.m. at 16,250 feet (4,953 meters). The engine turned a propeller with a diameter of 11 feet, 3 inches (3.429 meters).
The Mk.I’s best economical cruising speed was 212 miles per hour (341 kilometers per hour) at 20,000 feet (6,096 meters), and its maximum speed was 316 miles per hour (509 kilometers per hour) at 17,750 feet (5,410 meters) and 6,440 pounds (2,921 kilograms). The airplane’s range was 585 miles (941 kilometers). The Hurricane Mk.I could climb to 20,000 feet in 9.7 minutes.
The fighter was armed with eight Browning .303 Mark II machine guns mounted in the wings, with 334 rounds of ammunition per gun.
Peter Townsend described the Hurricane in his book, Duel of Eagles:
“. . . By December  we had our full initial equipment of sixteen aircraft. The Fury had been a delightful play-thing; the Hurricane was a thoroughly war-like machine, rock solid as a platform for eight Browning machine-guns, highly manoeuvrable despite its large proportions and with an excellent view from the cockpit. The Hurricane lacked the speed and glamour of the Spitfire and was slower than the Me. 109, whose pilots were to develop contempt for it and a snobbish preference for being shot down by Spitfires. But figures were to prove that during the Battle of Britain, machine for machine, the Hurricane would acquit itself every bit as well as the Spitfire and in the aggregate (there were more than three Hurricanes to two Spitfires) do greater damage among the Luftwaffe.”
—Duel of Eagles, Group Captain Peter Wooldridge Townsend, CVO, DSO, DFC and Bar, RAF. Cassell Publishers Limited, London, Chapter 13 at Pages 153–154.
At the beginning of World War II, 497 Hurricanes had been delivered to the Royal Air Force, enough to equip 18 squadrons. During the Battle of Britain, the Hurricane accounted for 55% of all enemy aircraft destroyed. Continuously upgraded throughout the war, it remained in production until July 1944. The final Hurrican, a Mk.IIc, PZ865, was flown for the first time by P.W.S. Bulman on 24 July 1944. A total of 14,503 were built by Hawker Aircraft Ltd., Gloster Aircraft Company, Austin Motor Company, and the Canadian Car and Foundry Company.
¹ Later, Group Captain Paul Ward Spencer Bulman, C.B.E., M.C., A.F.C. and Bar.
The KING has been graciously pleased to confer the Victoria Cross on the undermentioned officer in recognition of most conspicuous bravery : —
Flight Lieutenant James Brindley NICOLSON (39329) — No. 249 Squadron.
During an engagement with the enemy near Southampton on 16th August, 1940, Flight Lieutenant Nicolson’s aircraft was hit by four cannon shells, two of which wounded him whilst another set fire to the gravity tank. When about to abandon his aircraft owing to flames in the cockpit he sighted an enemy fighter. This he attacked and shot down, although as a result of staying in his burning aircraft he sustained serious burns to his hands, face, neck and legs.
Flight Lieutenant Nicolson has always displayed great enthusiasm for air fighting and this incident shows that he possesses courage and determination of a high order. By continuing to engage the enemy after he had been wounded and his aircraft set on fire, he displayed exceptional gallantry and disregard for the safety of his own life.
—The London Gazette, Number 34993, Friday, 15 November 1940, at Page 6569, Column 1
Peter Townsend wrote about Nick Nicolson’s battle in his history of the Battle of Britain, Duel of Eagles:
“Flight Lieutenant J.B. Nicolson of 249 Squadron was patrolling in his Hurricane west of Tangmere at seventeen thousand feet. He dived on some Ju. 88s when suddenly his Hurricane staggered. From somewhere behind bullets and cannon shells ripped through the hood, hit him in the foot and pierced his centre-tank. A searing mass of flame filled the cockpit. As he whipped into a steep turn he saw the offender, a Me. 110, slide below, diving hard. A wild resolve, stronger than reason, seized Nicolson. The cockpit a furnace, his dashboard ‘dripping like treacle’ and his hands fused by heat onto throttle and stick, he yelled, ‘I’ll get you, you Hun.’ And he went firing until the Me. 110 fell, until the frightful agony of his burns had passed the threshold of feeling. Then he struggled out of the cockpit and still wreathed in flames fell until the rush of cold air extinguished them. Only then did his mutilated hand fumble for the ripcord and somehow find strength to pull it. As if his sufferings were not already enough, some imbecile of a Home Guard fired at Nicolson and hit him fifty feet above the village of Millbrook in Hampshire.
“The gallant Nicolson was awarded the Victoria Cross. Of three thousand fighter pilots who fought in the battle ‘to defend the cause of civilization’ Nicolson alone among the defenders received the supreme award for valour. It was enough. The twenty-three-year-old pilot was typical of his young comrades. Alone in their tiny cockpits miles above the earth, there courage was of a peculiar kind which no medal, no material standard, could ever properly measure.”
— Duel of Eagles, Group Captain Peter Wooldridge Townsend, CVO, DSO, DFC and Bar, RAF. Cassell Publishers Limited, London, Chapter 23 at Pages 328–329.
Nick Nicolson’s fighter was a Hawker Hurricane Mk.I, P3576, with squadron markings GN A. It was in the third production block of 544 Hurricanes built by Hawker Aircraft Limited, Brooklands, between February and July 1940.
The Hurricane Mk.I was ordered into production in the summer of 1936. The first production airplane flew on 12 October 1937. The early production Hurricane Mk. I retained the wooden fixed-pitch propeller and fabric-covered wings of the prototype, though this would change with subsequent models. It was 31 feet, 4 inches (9.550 meters) long with a wingspan of 40 feet (12.192 meters) and overall height of 13 feet, 3 inches (4.039 meters). Its empty weight was 4,982 pounds (2,260 kilograms) and gross weight was 6,750 pounds (3,062 kilograms).
The Mk.I’s engine was a liquid-cooled, supercharged, 27.01 liter (1,648.96 cubic inches) Rolls-Royce R.M.1.S. Merlin Mk.III single-overhead-cam 60° V-12, rated at 990 horsepower at 2,600 r.p.m. at 12,250 feet (3,734 meters), and 1,030 horsepower at 3,000 r.p.m., at 10,250 feet (3,124 meters), using 87 octane aviation gasoline. The Merlin III drove the propeller through a 0.477:1 gear reduction ratio. It weighed 1,375 pounds (624 kilograms).
The fixed-pitch propeller was soon replaced with a three-bladed, two-pitch propeller, and then a three-bladed constant-speed propeller. Speed trials of a Mk.I equipped with a 10 foot, 9 inch (3.277 meters) diameter Rotol constant-speed propeller achieved a maximum True Air Speed in level flight of 316 miles per hour (509 kilometers per hour) at 17,750 feet (5,410 meters) at 3,000 r.p.m. The service ceiling was 33,750 feet (10,287 meters). The Mk.I’s range was 600 miles (966 kilometers) at 175 miles per hour (282 kilometers per hour).
The fighter was armed with eight Browning .303-caliber Mark II machine guns mounted in the wings.
At the beginning of World War II, 497 Hurricanes had been delivered to the Royal Air Force, enough to equip 18 squadrons. During the Battle of Britain, the Hurricane accounted for 55% of the enemy aircraft destroyed. Continuously upgraded throughout the war, it remained in production until 1944. A total of 14,503 were built by Hawker, Gloster and the Canadian Car and Foundry Company.
Eric James Brindley Nicolson was born 29 April 1917 at Hampstead, London, England. His parents were Leslie Gibson Nicolson and Dorothea Hilda Ellen Brindley. He was educated at the Tonbridge School in Kent, a private school which was founded in 1553. Nicolson was employed as an experimental engineer at Sir Henry Ricardo’s Engine Patents, Ltd., Shoreham, West Sussex, until joining the Royal Air Force in October 1936. On 21 December 1936, he was commissioned as a Pilot Officer. After flight training, P/O Nicolson served with No. 72 Squadron at RAF Church Fenton, North Yorkshire, August 1937–May 1940. He was promoted to Flying Officer, 12 May 1939.
On 29 July 1939, Eric Nicolson was married to Miss Muriel Caroline Kendall of Kirby Wharfe, Yorkshire.
Flying Officer Nicolson was assigned to No. 249 Squadron at RAF Leconfield, East Riding of Yorkshire, 15 May 1940, as an acting flight commander, and then promoted to Flight Lieutenant, 3 September 1940.
Following the action of 16 November, Flight Lieutenant Nicolson was hospitalized at the burn unit of Princess Mary’s Hospital, RAF Halton, Buckinghamshire, and then sent to a convalescent facility at Torquay, Devon. On 12 January 1941, he was promoted to Squadron Leader.
Nicolson returned to duty 24 February 1941, with 54 Operational Training Unit. From 21 September 1941 to 16 March 1942, he commanded No. 1459 Flight at RAF Hibaldstow, Lincolnshire. This was a night fighter unit, flying the Douglas Boston (P-70 Havoc). He was next assigned as a staff officer at Headquarters, 293 Wing, Royal Air Force, Alipore, West Bengal, India. After another staff assignment, Squadron Leader Nicolson was given command of 27 Squadron, a de Havilland Mosquito squadron at Agartala, in northeast India.
Nick Nicolson was promoted to Wing Commander 11 August 1944 and assigned to 3rd Tactical Air Force Headquarters in the Comilla Cantonment, East Bengal.
Wing Commander Eric James Brindley Nicolson, V.C., D.F.C., died 2 May 1945, while flying as an observer aboard a No. 355 Squadron Consolidated Liberator B Mk.VI, KH210, “R” (B-24J-85-CF 44-44071). At approximately 0250 hours, two engines caught fire. The bomber, piloted by Squadron Leader G.A. De Souza, RAF, and Flight Sergeant Michael Henry Pullen, Royal Australian Air Force, ditched in the Bay of Bengal, approximately 130 miles (209 kilometers) south of Calcutta. Of the eleven on board, only Pullen and one of the gunners survived.
Nicolson was the only RAF Fighter Command pilot awarded the Victoria Cross during World War II.
2 June 1941: Great Britain had been at war with Germany for 21 months. Its need for military equipment far exceeded the capacity of British industry, so the Empire looked across the North Atlantic Ocean to its former colonies, the United States of America.
The Royal Air Force ordered 140 Liberator B Mk.II bombers from Consolidated Aircraft Corporation of San Diego, California. The Consolidated Model LB-30 was a variant of the U.S. Army Air Corps B-24 four-engine long-range heavy bomber, but was built expressly for the RAF and had no direct Air Corps equivalent.
AL503 was the first Liberator Mk.II. It had made its first flight 26 May 1941, and was ready to be turned over to the Royal Air Force.
AL503 crashed on its acceptance flight, 2 June 1941. The aircraft was destroyed and all five on board were killed.
The Associated Press reported the accident:
Big Bomber Made for Britain Crashes in San Diego Bay; Four Members of Crew Perish
SAN DIEGO, Calif., June 2—(AP)—A $250,000 four-motored Consolidated bomber crashed and sank in San Diego Bay today, shortly after taking off from Lindbergh Field. Consolidated Aircraft Corp. officials said four of the crew members apparently perished.
The 25-ton craft was camouflaged and ready for delivery to Great Britain.
William B. Wheatley, 39, Chester, N.Y., chief test pilot for the Consolidated Aircraft Corp., apparently was at the controls. The Navy had taken over rescue operations, and details and names of crew members were not immediately available.
Witnesses said the huge plane left the airport on what appeared to be a normal takeoff, but that the bomber pulled up steep into a vertical climb instead of leveling off. At about 500 feet the plane apparently was in a stall.
The bomber then fell off to the left, and nosed down and the pilot, using the throttle appeared to have recovered. This difficulty was experienced over the airport, but by the time the pilot apparently had regained control of the craft it was flying over the water an an altitude of about 100 feet, the bomber again fell off to the left and the wing struck the water.
A Consolidated spokesman said the crash had “evidence of sabotage.”
The spokesman said the $250,000, 25-ton land bomber had been “thoroughly tested, and things like that just don’t happen.”
Believed dead were:
William Wheatley, 39, Chester, N.Y., chief test pilot for the company.
Allen T. Austen, 28, Kansas City, Mo., assistant test pilot.
Bruce K. Craig, 27, Chicago, engineer.
William H. Rieser, 33, Cambridge, Mass.
Lewis M. McAannon, 25, Woodstock, Ill., chief mechanic, was seriously injured. ¹
The bodies of Wheatley, Craig and Austin had not been recovered from the shattered bomber.
The impact with the water shattered the bomber, witnesses said, and it sank. Navy and small fishing vessels went to the rescue. The plane went down in an area between the San Diego shoreline and the naval air station.
The bomber, called “Liberator” by the Royal Air Force, was of all-metal construction, and its type is regarded as one of the most advanced military weapons. The Liberator can travel 230 miles an hour with a full bomb load over a 3,000 mile range. Orders for the huge land bomber originally were placed by the French, then taken over by the British.
The first B-24 was delivered to the British last Feb. 15 when the craft Consolidated Aircraft officials said established a record non-stop transcontinental flight of 9 hours, 57 minutes for planes of more than 5,000 pounds gross weight.
—The Eugene Guard, Vol. 50, No. 152, Monday, June 2, 1941, at Page 1 Column 6 and Page 2, Column 2
The Consolidated B-24 had first flown 29 December 1939. Chief Test Pilot Bill Wheatley was in command. Designed as a long-range heavy bomber for the U.S. Army Air Corps, it was a high-wing, four-engine monoplane with dual vertical fins and rudders. It had retractable tricycle landing gear. The bomber was flown by two pilots, with the crew including a navigator, bombardier, radio operator and several gunners.
The Royal Air Force Liberator B. Mk.I was essentially a B-24A. The Liberator Mk.II, though, was lengthened by extending the nose in front of the cockpit by 3 feet (0.914 meters). It was equipped with two power-operated gun turrets, one at the top of the fuselage, just aft of the wing, and a second at the tail.
The Liberator Mk.II was 66 feet, 4 inches (20.218 meters) long with a wingspan of 110 feet, 0 inches (33.528 meters) and overall height of 18 feet, 0 inches (5.486 meters). It was heavier than the Mk.I as a result of the longer fuselage and the heavy power turrets. The maximum gross weight was 64,250 pounds (29,143 kilograms).
The LB-30/Mk.II was powered by four air-cooled, supercharged 1,829.4-cubic-inch-displacement (29.978 liter) Pratt & Whitney Twin Wasp S3C4-G (R-1830-33) two-row fourteen-cylinder radial engines. These had a normal power rating of 1,100 horsepower at 2,550 r.p.m. to 6,100 feet (1,859 meters) and 1,000 horsepower at 2,700 r.p.m at 14,500 feet. The takeoff/military power rating was 1,200 horsepower at 2,700 r.p.m. to 5,000 feet (1,524 meters). The engines drove three-bladed Curtiss Electric variable-pitch propellers through a 2:1 gear reduction. The R-1830-33 was 4 feet, 0.06 inches (1.221 meters) in diameter and 5 feet, 3.48 inches (1.612 meters) long. It weighed 1,480 pounds (671 kilograms).
The Liberator Mk.II had a maximum speed of 263 miles per hour (423 kilometers per hour) at 15,000 feet (4,572 meters). Its service ceiling was 24,000 feet (7315 meters).
As was common with British bombers, the Liberator Mk.II was defended by Browning .303 Mk.II (7.7 × 56 mm) machine guns. Four were installed in the upper power turret and another four guns in the tail turret. Left and right waist positions each had two guns. One gun was mounted at the nose and one in the belly of the aircraft. This was a total of fourteen. The tail turret carried 2,200 rounds of ammunition and the top turret had 600 rounds.
The second Liberator Mk.II, AL504, became the personal transport of Prime Minister Winston Churchill, who named it Commando. In 1944, the aircraft was modified to the single vertical fin configuration of the PB4Y-2 Privateer. Commando disappeared over the Atlantic in 1945.
William Ballantine Wheatley was born at Chester, New York, 17 December 1902, the first of three children of William A. Wheatley, a public school superintendent, and Mabel Ballantine Wheatley. He was twice married, first, about 1927, to Esther C. Wheatley, of Massachussetts. His second marriage was to Miss Grace Lenore Ray, 18 April 1935, at Washington, D.C. They would have a son and two daughters.
After two years of college, Wheatley joined the U.S. Army Air Corps as an aviation cadet, 3 March 1925. He trained as a pilot at Brooks Field, Texas, and was commissioned as a 2nd lieutenant, 13 March 1926. On 4 May 1927, Lieutenant Wheatley was assigned to the 118th Observation Squadron, 43rd Division, Air Service, at Hartford, Connecticut, as a pilot and observer. He served in the Air Corps Reserve until 1937.
In 1928, Wheatley went to work for the Pratt & Whitney Aircraft Company as a test pilot. He was an air mail pilot in 1928-1929, and then, in February 1929, he became a test pilot for Reuben H. Fleet’s Consolidated Aircraft Corporation at Buffalo, New York. In 1935, Consolidated moved to its new headquarters at Lindbergh Field, San Diego, California. Wheatley moved with it. He and his family lived in a 3 bedroom home about three miles northeast of the airport. In 1940, his salary as chief test pilot of Consolidated was $50,000 per year. ²
Following Wheatley’s death, Beryl Arthur Erickson was assigned as chief test pilot for Consolidated.
¹ Lewis McCannon also died as a result of the crash.
20 May 1941: North American Aviation, Inc., test pilot Robert Creed Chilton took the first XP-51 for its maiden flight at Mines Field, Los Angeles, California. The XP-51 was the fourth production Mustang Mk.I built for the Royal Air Force, (North American serial number 73-3101) and assigned registration number AG348 .
The Mustang was reassigned to the U.S. Army Air Force, designated as XP-51, serial number 41-038, and sent to Wright Field, Dayton, Ohio, for evaluation.
Later, the XP-51 was extensively tested by the National Advisory Committee for Aeronautics (N.A.C.A.) at the Langley Memorial Aeronautical Laboratory, Langley Field, Hampton, Virginia.
Today, the restored XP-51 is in the collection of the E.A.A. AirVenture Museum at Oshkosh, Wisconsin.
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).
The Mustang 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 Normal Power rating of 880 horsepower at 2,600 r.p.m., at Sea Level, and 1,000 horsepower at 2,600 r.p.m. at 11,000 feet (3,353 meters). It had a Takeoff and Military Power rating of 1,150 horsepower at 3,000 r.p.m., to 11,800 feet (3,597 meters). The engine turned 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 (0.744 meters) wide. It weighed 1,310 pounds (594 kilograms).
The Mustang Mk.I had a maximum speed of 382 miles per hour (615 kilometers per hour) at 13,700 feet (4,176 meters), the Allison’s critical altitude, and cruise speed of 300 miles per hour (483 kilometers per hour). The service ceiling was 30,800 feet (9,388 meters) and range was 750 miles (1,207 kilometers).
The Mustang Mk.I was armed with four air-cooled Browning .303 Mk.II aircraft machine guns, two in each wing, and four Browning AN-M2 .50-caliber machine guns, with one in each wing and two mounted in the nose under the engine.
The Mk.I was 30 m.p.h. faster than its contemporary, the Curtiss P-40 Warhawk, though both used the same engine. Below 15,000 feet, the Mustang was also 30–35 m.p.h faster than a Supermarine Spitfire, which had a more powerful Roll-Royce Merlin V-12.
The XP-51 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.
Robert Creed Chilton was born 6 February 1912 at Eugene, Oregon, the third of five children of Leo Wesley Chilton, a physician, and Edith Gertrude Gray. He attended Boise High School in Idaho, graduating in 1931. Chilton participated in football, track and basketball, and also competed in the state music contest. After high school, Chilton attended the University of Oregon where he was a member of the Sigma Chi fraternity (ΣΧ). He was also a member of the Reserve Officers Training Corps (ROTC).
Bob Chilton enlisted as an Aviation Cadet in the U.S. Army Air Corps, 25 June 1937. He was trained as a fighter pilot at Randolph Field and Kelly Field in Texas, and was commissioned as a Second Lieutenant in 1938. Lieutenant Chilton was assigned to fly the Curtiss P-36 Hawk with the 79th Pursuit Squadron, 20th Pursuit Group, at Barksdale Field, Louisiana. Because of a medical condition, he was released from active duty, 1 April 1939.
At some time prior to 1940, Bob Chilton, married his first wife, Catherine. They lived in Santa Maria, California, where he worked as a pilot at the local airport.
In January 1941, Chilton went to work as a production test pilot for North American Aviation, Inc., Inglewood, California. After just a few months, he was assigned to the NA-73X.
Chilton married his second wife, Betty W. Shoemaker, 15 November 1951.
On 10 April 1952, Bob Chilton returned to active duty with the U.S. Air Force, with the rank of lieutenant colonel. He served as Chief of the Republic F-84 and F-105 Weapons System Project Office, Air Material Command, at Wright-Patterson Air Force Base, Dayton, Ohio, until 9 March 1957.
From 1958, Chilton was a vice president for Horkey-Moore Associates, an engineering research and development company in Torrance, California, founded by former North American aerodynamacist Edward J. Horkey. In 1961, he followed Horkey to the Space Equipment Corporation, parent company of Thompson Industries and Kerr Products, also located in Torrance. Chilton served as corporate secretary and contracts administrator.
Chilton married his third wife, Wilhelmina E. Redding (Billie E. Johnson) at Los Angeles, 26 July 1964. They divorced in 1972.
In 1965, Bob Chilton returned to North American Aviation as a flight test program manager. He retired in 1977.
Robert Creed Chilton died at Eugene, Oregon, 31 December 1994, at the age of 82 years.