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, NX19998, left front quarter view. (North American Aviation, Inc.)
Bell Model 209, N209J, prototype of the AH-1G Huey Cobra attack helicopter, in flight with landing skids retracted. (Bell Helicopter Company)
7 September 1965: First flight of the prototype Bell Model 209 attack helicopter. Test pilot William Thomas (“Bill”) Quinlan was in command. The duration of the flight was twelve minutes.
The Model 209 was a private venture, built in just seven months and rolled out at Fort Worth, Texas, 2 September 1965. The prototype aircraft combined the drive system, rotors and tail boom of the production UH-1C gunship with a streamlined fuselage which placed the two pilots in tandem.
The prototype was equipped with retractable landing gear which gave the 209 increased speed, but the expense and complexity were enough that this feature was not included on production aircraft.
This helicopter would be developed into the famous AH-1G Huey Cobra.
N209J, the Bell Model 209 prototype, shown in camouflage colors. (Bell Helicopter Company)
The second prototype, AH-1G 66-15246, was used by the Army for flight testing at Edwards Air Force Base, California, from 3 April to 21 April 1967.
66-15246 had an overall length of 52 feet, 11.65 inches (16.146 meters) with rotors turning. The fuselage was 44 feet, 5.20 inches (13.433 meters) long, and it was 3 feet, 0 inches (0.914 meters) wide. The HueyCobra had a short “stub wing” with a span of 10 feet, 11.60 inches (3.343 meters). Its angle of incidence was 14°. The wing’s area was 27.8 square feet (2.6 square meters). 66-15426 had an empty weight of 5,516 pounds (2,502 kilograms) and maximum gross weight of 9,500 pounds (4,309 kilograms).
Bell Model 209, N209J, prototype of the AH-1G Cobra, with landing skids extended. (U.S. Army)
The two-bladed Model 540 “door-hinge” main rotor was 44 feet, 0 inches (13.411 meters) in diameter. The blades had a chord of 2 feet, 3 inches (0.686 meters) and 10° negative twist. The main rotor turned counter-clockwise when viewed from above. (The advancing blade is on the helicopter’s right.) Normal rotor r.p.m. (power on) was 314–324 r.p.m., and power off, 304–339 r.p.m. The minimum transient rotor speed, power off, was 250 r.p.m.
The two blade tail rotor assembly had a diameter of 8 feet, 6 inches (2.591 meters) with a chord of 8.41 inches (0.214 meters). There was no twist. It was mounted on the left side of the pylon in a pusher configuration and turned counter-clockwise as seen from the helicopter’s left. (The advancing blade is above the axis of rotation.) The tail rotor pylon was cambered to allow aerodynamic forces in forward flight to “unload” the tail rotor.
Bell AH-1G Cobra three-view drawing. (U.S. Army Aviation Systems Test Activity)
The AH-1G was powered by a Lycoming LTC1K-4 (T53-L-13) turboshaft engine rated at 1,400 shaft horsepower, though it was derated to the helicopter’s transmission limit. The T53-L-13 is a two-shaft free turbine with a 6-stage compressor (5 axial-flow stages, 1 centrifugal-flow stage) and a 4-stage axial-flow turbine (2 high-pressure stages, 2 low-pressure power turbine stages). The T53-L-13 is 3 feet, 11.9 inches (1.217 meters) long, 1 foot, 11.0 inches (0.584 meters) in diameter and weighs 549 pounds (249 kilograms).
The speed of the Cobra was effected by the armament configuration, whether “clean,” light or heavy scout, or “heavy hog.” At 5,000 feet (1,524 meters), the cruise speed in the clean configuration was 138.0 knots (158.8 miles per hour, 255.6 kilometers per hour); light scout, 134.0 knots (154.2 miles per hour, 248.2 kilometers per hour); and heavy hog, 127.0 knots (146.2 miles per hour, 235.2 kilometers per hour). The maximum airspeed in level flight was 149.0 knots (171.5 miles per hour, 276.0 kilometers per hour); 144.0 knots (165.7 miles per hour, 266.7 kilometers per hour); and 136.5 knots (157.1 miles per hour, 252.8 kilometers per hour), respectively.
The limiting airspeed (VNE) was 190 knots (KCAS) (219 miles per hour, 352 kilometers per hour) below 3,000 feet (914 meters) density altitude.
In autorotation, the airspeed for the minimum rate of descent was 74.0 knots (85.2 miles per hour, 137.1 kilometers per hour) with the main rotor turning 294 r.p.m., resulting in a rate of descent of 1,750 feet per minute (8.89 meters per second).
Bell AH-1G Cobra. (U.S. Army)
The basic armament for the AH-1G Cobra was an Emerson M28 turret which could be equipped with one or two General Electric M134 Miniguns, or a combination of a Minigun with a Philco Ford M129 automatic grenade launcher, or two grenade launchers. Each Minigun was supplied with 4,000 rounds of 7.62 NATO ammunition, while a grenade launcher had 300 rounds of 40 × 53 millimeter high-velocity explosive ammunition.
Four hardpoints on the stub wing could be loaded with M18 7.62 NATO Minigun pods; XM35 pods, containing a short-barreled General Electric XM195 20 millimeter Gatling gun (a variant of the M61 Vulcan); rocket pods with seven or nineteen 2.75-inch unguided rockets.
The prototype Cobra, Bell Model 209 N209J, is in the collection of the U.S. Army Aviation Museum, Fort Rucker, Alabama, as is the second prototype, 66-15246.
de Havilland DH.110 WG236. (U.S. Naval Aviation News)
6 September 1952: At the Farnborough Air Show, an annual event held at the Royal Aircraft Establishment Farnborough, Hampshire, England, de Havilland test pilot John Douglas Derry, D.F.C., with flight test observer Anthony Max (“Tony”) Richards, put the prototype DH.110, WG236, into a supersonic dive from 40,000 feet (12,182 meters), pulling out just short of the airfield and the estimated 120,000 spectators.
John Douglas Derry, D.F.C. (Photograph courtesy of Neil Corbett, Test and Research Pilots, Flight Test Engineers)Anthony Max Richards (Flight)
Derry then made a high-speed, low-level circuit of the airfield, and as he straightened out, the airplane broke apart and crashed onto Observation Hill.
Both Derry and Richards were killed, as were 29 spectators. Another 63 were injured.
Flight reported:
This melancholy affair has, inevitably, received wide publicity, and several inaccurate reports have been printed. A member of the staff of Flight who witnessed the accident describes it as follows: “Two small white puffs of cloud appeared in a clear patch of sky north of the airfield, presumably showing where the D.H.110 had exceeded Mach 1 in its dive. After about a minute there were two loud reports in split-second succession. The lower part of the dive must have been near-sonic, for the aircraft appeared overhead—at about 1,000–1,500ft—at almost the same instant; the supersonic ‘bangs’ had scarcely overtaken the 110, although they had evidently been produced at least 12 miles away. The aircraft flew out of sight to turn and line-up for a low flight above the main runway, which it made from the south-west at a speed estimated as 600–650 m.p.h. It then turned left into the circuit and flew back over the northern boundary at about 400ft. The break-up appeared to begin just before a steep 90-degree turn towards the enclosures. Small fragments came away from the 110, which gained height as the two Avons and the nose became detached from the airframe. One engine fell on a crowded slope behind the caravan parks, causing most of the casualties; the other landed harmlessly farther south. The nose, following the same path as the power-units, hit the grass just in front of the packed enclosure parallel with the runway and broke up. A number of small pieces landed on the runway itself while the airframe, minus tail-unit, nose and engines, dropped comparatively gently into the north-west corner of the airfield.”
—FLIGHT and AIRCRAFT ENGINEER, No. 2277, Vol. LXII. Friday, 12 September 1952, at Page 344, Column 1
This image shows the de Havilland DH.110 breaking up in flight. One of the engines has fallen free and is trailing smoke. (Unattributed)
Film taken from the ground showed that as the airplane came level, the starboard outboard wing separated, followed by the port outboard wing. The aircraft pitched violently upward with an acceleration of more than 12 Gs, and the cockpit, engines and tail then disintegrated.
The DH-110’s swept wings placed the ailerons well aft of the airplane’s center of gravity. When the pilot began his bank to the right, away from the crowd, he also began to climb. This caused the wing outer panels to twist, resulting in unexpected stresses. The right wing failed in torsion. The resulting roll then caused the left wing to fail.
The flight crew was not faulted.
Changes were made in the location of the spectators and maneuvering aircraft at the airshow from that time forward.
The de Havilland DH.110 prototype impact at RAE Farnborough, 6 September 1952. This photograph was taken by a spectator, Herbert Orr. (Bentley Archive/Popperfoto/Getty Images)de Havilland DH.110 crash site. (Unattributed)The scene of the 1952 Farnborough Air Show disaster. (Coventry Telegraph)
The de Havilland DH.110 was a prototype all-weather interceptor intended for operation by the Fleet Air Arm from the Royal Navy’s aircraft carriers. It was a two-place, twin-engine swept-wing fighter capable of supersonic speed. WG236 was the first prototype, which made its first flight the previous year, 26 September 1951. At the time of the accident WG236 had flown approximately 125 hours. The second prototype, WG240, had been scheduled to fly the demonstration for the air show, but had to be replaced for maintenance reasons.
The DH.110 used the twin-tailboom configuration of de Havilland’s DH.100 Vampire and DH.112 Venom fighters, but the wings were swept to 45°.
WG236 was 51 feet, 8 inches (15.748 meters) long with a wingspan of 51 feet, 0 inches (15.545 meters) and height of approximately 11 feet (3.35 meters). Its maximum takeoff weight was 35,000 pounds (15,876 kilograms).
WG236 was powered by two Rolls-Royce Avon RA.3 engines The RA.3 was a single-spool axial-flow turbojet with a 12-stage compressor section and single-stage turbine. It was rated at 6,500-pounds-thrust (28.91 kilonewtons). The second prototype used the more powerful RA.7.
The DH.110 had a maximum speed of 610 knots (0.924 Mach) at Sea Level, and 536 knots (0.936 Mach) at 40,000 feet (12,182 meters).
Planned armament for the production fighter was four 30 millimeter ADEN cannon.
De Havilland DH.110 WG236. (BAE Systems)
Both airmen were posthumously awarded the Queen’s Commendation for Valuable Service in the Air.
CENTRAL CHANCERY OF THE ORDERS OF KNIGHTHOOD
St. James’s Palace. S.W. 1
12th September, 1952
The QUEEN has been graciously pleased to give orders for the publication of the names of the persons shown below as having received an expression of Commendation for valuable service in the air:—
QUEEN’S COMMENDATIONS FOR VALUABLE SERVICE IN THE AIR.
John Douglas Derry, D.F.C. (deceased), Test Pilot, de Havilland Aircraft Company, Ltd.
Anthony Max Richards (deceased), Flight Test Observer, de Havilland Aircraft Company, Ltd.
For services when testing an experimental aircraft.
John Douglas Derry was born 5 December 1921 at Cairo, Egypt. He was one of four children of Douglas Erith Derry, M.C., M.B., Ch.B., Professor of Anatomy at the Government Medical School there, and Margaret G. Ramsay Derry.
Derry was educated at the Dragon School, a preparatory school for boys in Oxford, England, and at Charterhouse, in Surrey. In 1939, he enlisted in the Royal Air Force as an aerial gunner and radio operator. He was assigned as a crewman on Lockheed Hudson bombers with Coastal Command, before being sent to Canada for pilot training in 1943. On his return to England he was “seconded” to the Air Transport Auxiliary.
Hawker Typhoon
Derry returned to combat operations in October 1944, flying Hawker Typhoons on close air support missions with No. 182 Squadron. Shortly after, he was transferred to No. 181 Squadron as a flight commander. In March 1945, Derry returned to No. 182 as the squadron’s commanding officer.
Distinguished Flying Cross (RAF Museum)
On 29 June 1945, Acting Squadron Leader Derry was awarded the Distinguished Flying Cross. His citation, published in The London Gazette, reads:
This officer has participated in a large number of sorties as air gunner and later pilot. He has at all times displayed great determination and skill and his courage has been of the highest order. In April 1945, he led his squadron in an attack against enemy gun positions. Despite intense opposition the attack was pressed home with great accuracy. The success of this operation was due in no small measure to Squadron Leader Derry’s gallant and skillful leadership. This officer has set a fine example to all.
—Fourth Supplement to The London Gazette of Tuesday, the 26th of JUNE, 1945, Numb. 37154, at Page 3405, Column 1.
Bronzen Leeuw
Her Majesty, Wilhelmina, The Queen of The Netherlands, awarded Acting Squadron Leader Derry the Bronzen Leeuw (Bronze Lion).
After No. 182 Squadron was disbanded 30 September 1945, Squadron Leader Derry was appointed commanding officer of the Day Fighter Leader School at the Central Flying School, flying the Hawker Tempest.
After being released from service, Derry became an experimental and production test pilot for Vickers Supermarine. In October 1947, he moved to de Havilland.
On 12 April 1948, Derry flew a de Havilland DH.108 to set a Fédération Aéronautique Internationale (FAI) World Record for Speed over a Closed Circuit of 100 Kilometers without Payload, averaging 974.026 kilometers per hour (605.232 miles per hour).¹ On 6 September 1948, Derry exceeded the speed of sound in the de Havilland DH.108. He was awarded the Gold Medal of the Royal Aeronautical Club. The Royal Automobile Society awarded Derry The Segrave Trophy, “for the most outstanding demonstration of transportation by land, air or water: The Spirit of Adventure.”
The Segrave Trophy of the Royal Automobile Society. (RAS)
More than one member of Flight‘s staff was proud to know John Derry—a fine-looking young man and an inspiring personality—and on occasions to talk of flying and testing with him. We recall his cheerful unassuming manner, his completely straightforward and natural approach to any topic, and his firm opinion upon matters which he himself had studied and investigated. He was undoubtedly one of what we now call the new generation of test pilots, men who must be able to back their flying experience and skill as pilots with a full technical understanding.
—FLIGHT and AIRCRAFT ENGINEER, No. 2277, Vol. LXII. Friday, 12 September 1952, at Page 344, Column 2
The prototype Bristol Type 167, G-AGPW, takes off from Filton Aerodrome, 11:30 a.m., 4 September 1949. Hundred of Bristol employees are lining the runway. (Alfred Thompson)
4 September 1949: At 11:30 a.m., Sunday morning, the prototype Bristol Brabazon Mk.I, G-AGPW, made its first flight at Filton Aerodrome. Chief Test Pilot Arthur J. “Bill” Pegg was in command with Walter Gibb as co-pilot. An 8-man flight test crew was also aboard. A crowd of spectators, estimated at 10,000 people, were present.
The flight test crew of the Bristol Brabazon. Bill Pegg is at center. (Unattributed)
Designed as a transatlantic commercial airliner, development of the Type 167 began in 1943. The Mk.I prototype, G-AGPW, had been rolled out in December 1948. On 3 September 1949, the flight test crew performed a series of taxi tests.
The first flight lasted 26 minutes. The Brabazon had reached 3,000 feet (914 meters) and 160 miles per hour (257 kilometers per hour).
Bristol Brabazon Mk.I G-AGPW runs up its engines. (Unattributed)
The Bristol Aeroplane Company Type 167 Brabazon Mk.I was a very large low-wing monoplane, designed to carry 100 passengers on transatlantic flights. it had been named to honor John Theodore Cuthbert Moore-Brabazon 1st Baron Brabazon of Tara, was the first airplane pilot to be issued an aviator’s certificate by the Royal Aero Club of the United Kingdom. He had previously been assigned certificate number 40 of the Fédération Aéronautique Internationale. He was issued Certificate Number 1 in England. He was a very important figure in the development of the British aeronautical industry.
The Bristol Brabazon Mk.I under construction.
The Type 167 was slightly larger than the United States Air Force Convair B-36A intercontinental strategic bomber. It was 177 feet, 0 inches (53.950 meters) long with a wingspan of 230 feet, 0 inches (70.104 meters) and overall height of 50 feet, 0 inches (15.240 meters). The fuselage had a maximum diameter of 25 feet (7.62 meters).
The leading edge of the inboard section of the Brabazon’s wing was swept 4° 16′ and had no dihedral, while the outer section was swept 14° 56′ with 2° dihedral. The wings had an angle of incidence of +3° 30′. The chord narrowed from 31 feet, 0 inches (9.449 meters) at the root, to 10 feet, 0 inches (3.048 meters) at the tip. The wings’ maximum thickness was 6 feet, 6 inches (1.981 meters). The Mk.I’s wing area was 5,317 square feet (494 square meters).
The horizontal stabilizer had a span of 75 feet, 0 inches (22.860 meters). The angle of incidence was +2° and there was no dihedral. The stabilizer’s area was 692 square feet (64.3 square meters).
The airplane’s empty weight was 169,500 pounds (76,884 kilograms), and its maximum takeoff weight of 290,000 pounds (131,542 kilograms). For the first flight, its gross weight was 200,000 pounds (90,718 kilograms).
Bristol Brabazon Mk.I G-AGPW.
The prototype was powered by eight air-cooled, supercharged, 3,271.87-cubic-inch-displacement (53.62 liter) Bristol Centaurus 20 eighteen-cylinder radial engines. They had a cruise power rating of 1,640 horsepower at 22,000 feet (6,706 meters); maximum continuous power and maximum climb power rating of 2,190 horsepower at 5,000 feet (1,524 meters); and 2,500 horsepower for takeoff. Each pair of engines drove a set of coaxial counter-rotating three-bladed Rotol constant-speed wooden propellers with a diameter of 16 feet, 0 inches (4.877 meters).
“Each Bristol Centaurus engine was coupled to a propeller gearbox at a 32-degree angle.” (Airbus, Filton)
Power was transmitted from each engine by an angled drive shaft to separate beveled gears in a dual reduction gear unit. The reduction gear ratio was 0.400:1. For one-engine-out operation, the effected propeller would be feathered, while the other engine of the pair continued to power the other counter-rotating propeller. The propellers were reversible for braking on landing.
Turboprop engines were planned for the Brabazon Mk.II.
Bristol Brabazon Mk.I G-AGPW flying overhead reveals the double sweep of the wings. (BAE Systems)
Estimated performance of the Brabazon Mk.I (before flight testing was completed) was a cruise speed of 250 miles per hour (402 kilometers per hour), and maximum speed of 300 miles per hour (483 kilometers per hour), both at 25,000 feet (7,620 meters), the airplane’s service ceiling.
The maximum fuel capacity of the Mk.I was 13,650 gallons (51,671 liters), giving a maximum range at cruise speed of 5,460 miles (8,787 kilometers). This was sufficient for a flight from London to New York with the required fuel reserve.
Only one Brabazon Mk.I was built. The prototype Mk.II was never completed. The project was cancelled in 1952. The total cost of the Brabazon program was approximately £6,500,000 (estimated at £170,981,807, or $221,489,833 in 2017). G-AGPW was eventually scrapped.
Bristol Brabazon Mk. I G-AGPW landing at Farnborough, September 1950. (BAE Systems)
This British Pathé news film shows the Brabazon in flight:
Thanks to regular “This Day in Aviation” reader, Mr. Lynn Brown, for suggesting this subject.
Northrop F-5G (F-20A) Tigershark prototype 80-0062 during its first flight, 30 August 1982. (Northrop Grumman)
30 August 1982: Northrop test pilot Russell J. Scott made the first flight of the F-5G Tigershark prototype, N4416T, (Northrop serial number GG.1001) at Edwards Air Force Base, California. During the 40 minute flight the Tigershark, which would be re-designated F-20A two months later, reached an altitude of 40,000 feet and speed of Mach 1.04.
(Russ Scott, a former U.S. Air Force pilot, had been one of 11 pilots selected in 1961 to fly the Central Intelligence Agency’s ultrasecret Lockheed A-12 “Oxcart” Mach 3+ reconnaissance aircraft, though he left the program before the A-12 became operational.)
The F-5G was developed by Northrop at the request of the Department of State. U.S. policy at the time prevented the export of front line fighters, like the Grumman F-14 Tomcat and McDonnell Douglas F-15 Eagle, to Allied nations outside of NATO, with the exception of Australia, Israel, Egypt and Iran. Since the Republic of China was building the F-5E under license for its air force, the State Department had asked Northrop to design an advanced fighter based on that earlier type that could be produced in Taiwan.
Northrop F-5G (F-20A) Tigershark prototype, 82-0062. (U.S. Air Force)
Changing political administrations restricted U.S. export policies and the projected sales of the F-5G, now designated F-20A, did not materialize. The fighter competed against the General Dynamics F-16 Fighting Falcon for an Air Force contract. The F-20A was considered to be as good, and in some ways, superior to the F-16. It was also less expensive. Other factors, though, resulted in the order for the General Dynamics fighter.
The Northrop F-5G (F-20A)Tigershark prototype, N4416T, lands at Edwards Air Force Base, California. after its first flight, escorted by a Northrop F-5F Tiger II, N3139Y. (U.S. Air Force)
Developed from the earlier F-5E Tiger II, the F-5G/F-20A Tigershark was a Mach 2+ single-seat, single-engine, light-weight fighter. It was 46 feet, 6 inches (14.173 meters) long, with a wingspan of 26 feet, 8 inches (8.128 meters) with launch rails, and overall height of 13 feet, 10 inches (4.216 meters). The F-20A had an empty weight of 11,220 pounds (5,089 kilograms) and maximum takeoff weight of 26,544 pounds (12,040 kilograms).
The F-20A was powered by a single General Electric YF404-GE-100 engine. The F404 is a two-spool, axial-flow, low bypass turbofan with afterburner. It has a 3-stage fan section, 7-stage compressor and 2-stage (1 high- and 1 low-pressure stage) turbine. The the F404-GE-100 is rated at 17,000 pounds of thrust (75.62 kilonewtons) with afterburner. The engine has a maximum diameter of 2 feet, 10.8 inches (0.884 meters), is 13 feet, 2.8 inches (4.034 meters) long, and weighs 2,230 pounds (1,012 kilograms).
From a cold start, the prototype fighter could climb to 34,000 feet (10,363 meters) in 2½ minutes. It could accelerate from 0.3 mach to 0.9 Mach in 27 seconds. The F-20A had a maximum speed of Mach 2.1 at 36,000 feet (10,973 meters)—1,387 miles per hour (2,232 kilometers per hour). Its service ceiling was 55,000 feet (16,764 meters). The maximum range with external tanks was 1,715 miles (2,760 kilometers).
The Tigershark’s armament consisted of two Pontiac M39A2 20mm autocannon with 280 rounds of ammunition per gun, and two AIM-9 Sidewinder air-to-air missiles carried on the wingtips.
Only three F-20As were built. N4416T (82-0062) crashed during a demonstration flight at Suwon Air Base, Republic of South Korea, 10 October 1984. The aircraft was destroyed and Northrop pilot Darrell E. Cornell was killed. The second F-20, N3986B, crashed at Goose Bay, Newfoundland, Canada, 14 May 1985, under similar circumstances, killing David Barnes. Investigations found that both pilots had lost consciousness due to high-G maneuvers. The third Northrop F-20A, N44671 (82-0064), is on display at the California Science Center, Exposition Park, Los Angeles, California.
Northrop F-20A Tigershark 82-0062 in flight over General William J. Fox Airfield (WJF), northwest of Lancaster, California. (U.S. Air Force)
