Tag Archives: Prototype

1 June 1939

Focke-Wulf Fw 190 V1, D-OPZE, the first prototype. (Focke-Wulf Flugzeugbau AG)
Focke-Wulf Fw 190 V1, W.Nr. 0001, D-OPZE, the first prototype. (Focke-Wulf Flugzeugbau AG)

1 June 1939: At Bremen, Germany, Focke-Wulf Flugzeugbau AG chief test pilot Hans Sander took the first prototype of a new fighter, Fw 190 V1, W.Nr. 0001, registration D-OPZE, for its first flight.

Dipl. Ing. Hans Sander

The Fw 190 was designed as a fast, light-weight fighter with a powerful engine, easy to maintain under field conditions and able to absorb a reasonable amount of combat damage. The landing gear had a wide track which improved ground handling and was an advantage when operating on unimproved airfields. The mechanism used the gear’s own weight to lower it into place. Another interesting feature was to use of pushrods and bearings in place of the common cables and pulleys used to operate the flight controls. This gave a more precise, responsive operation. Also, the recent introduction of vacuum forming allowed a large one-piece “bubble” canopy to be used rather than the acrylic plastic/metal framework which was used in other fighters, such as the Messerschmitt Bf 109.

V-1 near completion.
The prototype Focke-Wulf Fw 190 V1 W.Nr. 0001. (Focke-Wulf Flugzeugbau AG)

Focke-Wulf frequently named its airplanes after birds. The Fw 190 was known as the Würger, or Shrike.

Fw 190 V1 (Versuchsflugzeug 1) was 8.730 meters (28 feet, 7¾ inches) long with a wingspan of 9.500 meters (31 feet, 2 inches). It weighed approximately 3,000 kilograms (6,615 pounds).

Focke-Wulf Fw 190 V1, D-OPZE, the first prototype. (Focke-Wulf Flugzeugbau AG)
Focke-Wulf Fw 190 V1, D-OPZE, the first prototype, during flight. The long landing gear struts were made necessary by the use of a large diameter propeller. (Focke-Wulf Flugzeugbau AG)

D-OPZE was powered by an experimental air-cooled, supercharged 55.4-liter (3,380.4 cubic inch) BMW 139 two-row, 18-cylinder, radial engine which produced 1,529 horsepower. This engine had been developed from the nine-cylinder Pratt & Whitney Hornet (R-1690) which Bayerische Motoren Werke AG (BMW) built under license. (A redesign of the BMW 139 engine resulted in the 14-cylinder BMW 801 which was used in the production Fw 190.)

The propeller was a three-bladed Vereingite Deutsche Metallwerke (VDM) variable-pitch unit with a diameter of 3.460 meters (11 feet, 4¼ inches). It was driven at 54% of engine speed through a gear reduction unit.

To minimize aerodynamic drag, the large radial engine was tightly cowled and a large propeller spinner used. Cooling air entered through an opening at the center of the spinner and a fan between the propeller and the front of the engine circulated air. This was unsatisfactory and was significantly changed with the second prototype.

Focke-Wulf Fw 190 V1 W.Nr. 0001, D-OPZE. (Focke-Wulf Flugzeugbau AG)

After testing by Focke-Wulf at Bremen, Fw 190 V1 was flown to the Luftwaffe test site at Rechlin-Lärz Airfield. Its identification markings were changed to FO+LY. Later, they were changed again, to RM+CA. V1 continued to be used for testing until 29 March 1943.

Fw 190 V1 after the original spinner was replaced. The cooling fan behind the propeller is visible. The prototype is now marked FO+LY. (Focke-Wulf Flugzeugbau AG)
Focke-Wulf Fw 190 V1 W.Nr. 0001 with modified engine cowling. The prototype is now camouflaged and marked with the Luftwaffe Balkenkruz and the swastika of the Deutsches Reich. The identification marks have been changed to  FO+LY. (Focke-Wulf Flugzeugbau AG)

The Fw 190 was the most effective of Germany’s world War II fighters. More than 20,000 were built in 16 variants. The Focke-Wulf factory at Marienburg and the AGO Flugzeugwerke at Oschersleben were frequently attacked by Allied bombers.

A captured Focke-Wulf Fw 190 in flight. (U.S. Air Force)
A captured Focke-Wulf Fw 190 G-3 DN+FP, W.Nr. 160016, in flight near Wright Field, Ohio, 26 May 1944. (U.S. Air Force)

A Focke-Wulf Fw 190 G-3 fighter bomber, W.Nr. 160016, which had been captured in Italy, was flight tested by the U.S. Army Air Force at Wright Field, Ohio, from 25 March to 15 April 1944, flown by Major Gustav Edward Lundquist, U.S. Army Air Force. In a report dated 26 May 1944, it was described as having a length of 29.1 feet (8.87 meters) and wingspan of 34.5 feet (10.52 meters), and was tested with maximum gross weight of 8,535 pounds (3,871 kilograms).

This aircraft was powered by an air-cooled, supercharged and fuel-injected 41.744 liter (2,547.4 cubic inch) BMW 801-D two-row, fourteen-cylinder radial engine which produced 1,750 horsepower at 2,700 r.p.m. with 41.1 inches of manifold pressure (1.39 bar). It could climb at 4,000 feet per minute (20.32 meters per second) and reach 20,000 feet (6,096 meters) in 7.3 minutes. 160016 had a maximum airspeed of 415 miles per hour (668 kilometers per hour) at 22,000 feet (6,706 meters). The service ceiling was 36,100 feet (11,003 meters).

The fighter was described to have performance “definitely weaker than standard AAF fighters at altitudes above 28,000 feet.”  [8,534 meters]

The Fw 190 G-3 was armed with two Waffenfabrik Mauser AG MG151/20 20 mm autocannon with 550 rounds of ammunition.

Focke-Wulf Fw 190 G-3 DN+FP, W.Nr. 160016, in flight near Wright Field, Ohio, May 1946. (U.S. Air Force)

(Two months later, Major Lundquist was in Europe, flying with the 486th Fighter Squadron, 352nd Fighter Group. On 29 July 1944, his North American Aviation P-51D-5-NA Mustang, 44-13395, was shot down by a Messerschmiit Bf 109 G-6 near Merseberg, Germany. Lundquist was captured and remained a Prisoner of War until the end of World War II. He was officially credited with 2 enemy aircraft destroyed. After the war, he returned to Wright Field and flight test. On 2 September 1946, Major Lundquist won the Thompson Trophy Race (J Division) while flying a Lockheed P-80A Shooting Star. Remaining in the Air Force for 29 years, he rose to the rank of brigadier general.)

Focke-Wulf-Fw-190-WNr-50046-in-flight-01
Focke-Wulf Fw 190 G-3 DN+FP, W.Nr. 160016, from above and behind. (U.S. Air Force)

© 2018, Bryan R. Swopes

30 May 1958

Douglas DC-8-11 N8008D takes of from Long Beach Airport, 10:10 a.m., 30 May 1958.
Douglas DC-8-11 N8008D takes of from Long Beach Airport, 10:10 a.m., 30 May 1958. The heavy exhaust smoke is a result of water injection. (Los Angeles Public Library)

30 May 1958: Douglas Aircraft Company Flight Operations Manager and engineering test pilot Arnold G. Heimerdinger, with co-pilot William M. Magruder and systems engineer Paul H. Patten, were scheduled to take off from Long Beach Airport (LGB) on the coast of southern California, at 10:00 a.m., to make the first flight of the new Douglas DC-8 jet airliner, c/n 45252, FAA registration N8008D.

Crowds of spectators, estimated as many as 50,000 people, were surrounding the airport. For this first test flight, the Federal Aviation Administration required a minimum of five miles visibility. Typical Southern California coastal low clouds and fog caused a ten minute delay.

Taking off at 10:10 a.m., N8008D climbed out to the south over the Pacific Ocean. Escorted by a company-owned Douglas DC-7 engineering and photo plane and a Lockheed T-33A Shooting Star chase, the DC-8 climbed to 11,000 feet (3,353 meters) and went through a series of pre-planned flight maneuvers and systems checks. Heimerdinger took the airliner north to Edwards Air Force Base in the high desert of southern California, where the full flight test program would be carried out. The total duration of the first flight was 2 hours, 10 minutes.

In an article written the following year, Heimerdinger said that the DC-8 was easy to fly and never presented any difficulties during the test program.

Douglas DC-8 N8008D accompanied by a Cessna T-37. (Douglas Aircraft Company)
Douglas DC-8 N8008D accompanied by a U.S. Air Force Cessna T-37 chase plane during a test flight near Edwards Air Force Base, California. (Douglas Aircraft Company)

The Douglas DC-8 Jetliner is a commercial airliner, a contemporary of the Boeing 707 and Convair 880. It was operated by a flight crew of three and could carry up to 177 passengers. It was powered by four turbojet engines mounted on pylons suspended below the wings. The wings’ leading edges were swept to 30° as were the vertical fin and horizontal tailplane. The airplane is 150 feet, 6 inches (45.872 meters) long with a wingspan of 142 feet, 5 inches (43.409 meters) and overall height of 42 feet, 4 inches (12.903 meters). N8008D was a Series 10 version. It had an empty weight of 119,767 pounds (54,325 kilograms) and maximum takeoff weight of 273,000 pounds (123,831 kilograms).

N8008D was originally powered by four Pratt & Whitney JT3C-6 turbojet engines, the same engines which powered its Boeing rival. It is a two-spool, axial-flow turbojet engine with a 16-stage compressor and 2-stage turbine. The JT3C-6 was rated at 11,200 pounds of thrust (49.82 kilonewtons), and 13,500 pounds (60.05 kilonewtons) with water/methanol injection). The JT3C is 11 feet, 6.6 inches (3.520 meters) long, 3 feet, 2.9 inches (0.988 meters) in diameter, and weighs 4,235 pounds (1,921 kilograms). The engines were later upgraded to JT3D-1 turbofan engines which produced 17,000 pounds of thrust.

The DC-8-10 series had a cruising speed of 0.82 Mach (542 miles per hour/872 kilometers per hour) at 35,000 feet (10,668 meters). Its maximum range was 5,092 miles (8,195 kilometers).

Douglas DC-8 N9604Z. (Long Beach Public Library)

On 21 August 1961, a Douglas DC-8-43, N9604Z, c/n 45623, Line Number 130, flown by Chief Test Pilot William Magruder, Paul Patten, Joseph Tomich and Richard Edwards, climbed to 50,090 feet (15,267 meters) near Edwards Air Force Base. Magruder put the DC-8 into a dive, and the airplane reached Mach 1.012 (668 miles per hour/1,075 kilometers per hour) while descending through 41,088 feet (12,524 meters). The airliner maintained this supersonic speed for 16 seconds.

This was the first time that a civil airliner had “broken the Sound Barrier.” An Air Force F-100 Super Sabre and F-104 Starfighter were chase planes for this flight. Reportedly, the F-104 was flown by the legendary test pilot, Colonel Chuck Yeager.

Douglas DC-8-43 N9604Z is accopmanied by a U.S. Air Force Lockheed F-104A Starfighter, near Edwards Air Force base, California.
Douglas DC-8-43 N9604Z, in Canadian Pacific livery, is accompanied by a U.S. Air Force Lockheed F-104A-10-LO Starfighter, 56-0749, near Edwards Air Force Base, California. The dark sky suggests that the airplanes are at a very high altitude. (Unattributed)

N9604Z was powered by four Rolls-Royce Conway RCo.12 Mk 509 two-shaft axial-flow turbofan engines, rated at 17,500 pounds of thrust (77.844 kilonewtons) at 9,990 r.p.m. The 509 is 11 feet, 3.9 inches (3.452 meters) long, 3 feet, 6.2 inches (1.072 meters) in diameter, and weighs 4,542 pounds (2,060 kilograms).

N9604Z was delivered to Canadian Pacific Airlines, 15 November 1961, registered CF-CPG, and named Empress of Montreal. It later flew under CP Air as Empress of Buenos Aires. It was scrapped at Opa Locka Municipal Airport, north of Miami, Florida, in May 1981.

In 1960, N8008D was converted to the DC-8-51 configuration. With a change to the more powerful JT3D-1 turbofan engines, the airliners maximum takeoff weight was increased to 276,000 pounds (125,191 kilograms).

After the flight test and commercial certification program was completed, on 21 June 1961, Douglas leased N8008D to National Airlines, based at Miami, Florida. One year later, 20 June 1961, it was sold to Trans International Airlines. TIA leased the DC-8 to Lufthansa, 11 May 1965, and to Canadian Pacific, 1 October 1966. It was re-registered CF-CPN and named Empress of Santiago.

Douglas DC-8-51 N8008D, owned by Trans International Airways, was photographed at London Gatwick Airport, 23 July 1966. (RuthAS)
Douglas DC-8-51 N8008D, owned by Trans International Airways, was photographed at London Gatwick Airport, 23 July 1966. (RuthAS)

TIA sold the DC-8 to Delta Airlines, Atlanta, Georgia, 1 October 1967. It reverted to its FAA-assigned registration, N8008D. Delta gave it fleet number 800.

In March 1979, Delta sold N8008D to F.B. Myers and Associates. On 1 April, F.B. Myers leased the it to Aerovias de México, S.A. de C.V. (Aeroméxico). The DC-8 was assigned Mexican registration XA-DOE and named Quintana Roo.

The first Douglas DC-8 was placed in storage at Marana-Pinal Airpark, north of Tucson, Arizona, 7 January 1982. In May 1989, it was sold to Agro Air, a Caribbean regional cargo airline. It remained at Marana and was used as a source of parts. In 2001, c/n 45252 it was scrapped.

Between 1959 and 1972, Douglas produced 556 DC-8s in passenger and freighter configurations.

A.G. Heimerdinger
Arnold George Heimerdinger, Flight Operations Manager, Douglas Aircraft Company. (Photograph courtesy of Neil Corbett, Test and Research Pilots, Flight Test Engineers)

Arnold George Heimerdinger was born in Manchester Township, Michigan, 7 December 1910. His parents were Charles and Minnie L. Uphaus Heimerdinger. He studied electrical engineering at the University of Michigan. Heimerdinger married Miss Mary Aileen Eggert 19 August 1935.

A.G. Heimerdinger was commissioned as an ensign in the United States Navy, 27 November 1942 and served as a Naval Aviator until he was released from active duty, 14 October 1945.

Heimerdinger worked as an engineering test pilot for the Federal Aviation Administration, and he flew certification tests of the Boeing 377 Stratocruiser, Convair 240 and 340 Metroliner, and the Lockheed L-640 and L-1049 Constellation.

He joined the Douglas Aircraft Company at Santa Monica, California, in 1952 and remained with the company until he retired in 1974. He was the project test pilot for the Douglas DC-6B and the DC-7. Transferring to Douglas’ Long Beach Division, a few miles southeast, he was project test pilot for the DC-8 and DC-9 jet airliners.

Arnold G. “Heimie” Heimerdinger died at Santa Monica, California, 17 July 1975.

© 2018, Bryan R. Swopes

29 May 1940

Vought-Sikorsky Aircraft Division XF4U-1 Corsair prototype, Bu. No. 1443, in flight. (Rudy Arnold Collection/NASM)

29 May 1940: Vought-Sikorsky Aircraft Division test pilot Lyman A. Bullard, Jr. took the U.S. Navy’s new prototype fighter, the XF4U-1, Bu. No. 1443, for its first flight at the Bridgeport Municipal Airport, Bridgeport, Connecticut. Designed by Rex Buren Beisel, the prototype would be developed into the famous F4U Corsair.¹

Rex Buren Beisel, designer of the F4U-1 Corsair, at left, with Corsair pilot Major Gregory Boyington, USMCR, circa 1942. (Unattributed)

The F4U Corsair is a single-place, single-engine fighter, designed for operation from the U.S. Navy’s aircraft carriers. The XF4U-1 prototype was 30 feet (9.144 meters) long with a wing span of 41 feet (12.497 meters) and overall height of 15 feet, 7 inches (4.750 meters). It had an empty weight of 7,576 pounds (3,436 kilograms) and gross weight of 9,374 pounds (4,252 kilograms).

Vought-Sikorsky XF4U-1 Corsair, Bu. No. 1443
Vought-Sikorsky XF4U-1 Corsair, Bu. No. 1443. The airplane’s wings are painted yellow. (Vought-Sikorsky Aircraft Division)

The XF4U-1 was first powered by an experimental air-cooled, supercharged, 2,804.4-cubic-inch-displacement (45.956 liters) Pratt & Whitney R-2800 X-2 (Double Wasp A2-G), and then an R-2800 X-4 (Double Wasp SSA5-G), both two-row 18-cylinder radial engines. The R-2800 X-4 was an X-2 with an A5-G supercharger. The R-2800 X-2 had a compression ratio of 6.65:1 and was rated at 1,500 horsepower at 2,400 r.p.m. at 7,500 feet (2,286 meters). The X-4 was rated at 1,600 horsepower at 2,400 r.p.m. at 3,500 feet (1,067 meters); 1,540 horsepower at 2,400 r.p.m. at 13,500 feet (4,115 meters); 1,460 horsepower at 2,400 r.p.m. at 21,500 feet (6,553 meters); and 1,850 horsepower at 2,600 r.p.m for takeoff. The engine drove a 13 foot, 4 inch (4.064 meter) diameter, three-bladed, Hamilton Standard Hydromatic constant-speed propeller through a 2:1 gear reduction. The X-4 had a compression ratio of 6.66:1 and used a two-speed, two-stage supercharger. This was the most powerful engine and largest propeller used on any single engine fighter up to that time. The R-2800 X-4 was 4 feet, 4.50 inches (1.334 meters) in diameter and 7 feet, 4.81 inches (2.256 meters) long. It weighed 2,500 pounds (1,134 kilograms).

The size of the propeller was responsible for the Corsair’s most distinctive feature: the inverted gull wing. The width of the wing (chord) limited the length of the main landing gear struts. By placing the gear at the bend, the necessary propeller clearance was gained. The angle at which the wing met the fuselage was also aerodynamically cleaner.

Vought Aircraft Division XF4U-1, front. (Vought Sikorsky VS-2612)
Vought-Sikorsky XF4U-1 Corsair, front, 19 April 1941. (Vought-Sikorsky VS-2612)
Vought Aircraft Division XF4U-1, right front quarter view. (Vought-Sikorsky VS-2618)
Vought-Sikorsky XF4U-1 Corsair, right front quarter view, 19 April 1941. (Vought-Sikorsky VS-2618)
Vought Aircraft Division XF4U-1, right profile (Vought-Sikorsky VS-2619)
Vought-Sikorsky XF4U-1 Corsair, right profile, 19 April 1941. (Vought-Sikorsky VS-2619)
Vought-Sikorsky XF4U-1, right rear quarter, 26 May 1940. (Vought-Sikorsky VS-1414/ cropped image from Connecticut Air & Space Center)
Vought Aircraft Division XF4U-1, rear, 26 May 1940. (Vought-Sikorsky VS-1407)
Vought-Sikorsky XF4U-1 Corsair, rear, 26 May 1940. (Vought-Sikorsky VS-1407)
Vought Aircraft Division XF4U-1, left side, wings folded, 26 May 1940. (Vought-Sikorsky VS-1416)
Vought-Sikorsky XF4U-1, left side, wings folded, 26 May 1940. (Vought-Sikorsky VS-1416)

The XF4U-1 prototype had a maximum speed of 378 miles per hour (608 kilometers per hour) at 23,500 feet (7,163 meters). Although it has been widely reported that it was the first U.S. single-engine fighter to exceed 400 miles per hour (643.7 kilometers per hour) in level flight, this is actually not the case. During a flight between Stratford and Hartford, Connecticut, the prototype averaged a ground speed 405 miles per hour (652 kilometers per hour). This was not a record flight, and did not meet the requirements of any official speed record.

Several changes were made before the design was finalized for production. Fuel tanks were removed from the wings to make room for six Browning AN-M2 .50-caliber machine guns and ammunition. A new tank was placed in the fuselage ahead of the cockpit. This moved the cockpit rearward and lengthened the nose.

On 11 July 1940, the XF4U-1 was low on fuel. Rather than returning to Bridgeport, test pilot Boone Tarleton Guyton made a precautionary landing on a golf course at Norwich, Connecticut. The grass was wet from rain and the prototype ran into the surrounding trees. Guyton was not injured, but 1443 was seriously damaged. Vought-Sikorsky repaired it and it returned to flight testing about two months later.

Vought-Sikorsky F4U-1 Corsair, Bu. No. 2170, with test pilot Willard Bartlett Boothby, 24 October 1942. (Rudy Arnold Collection/National Air and Space Museum NASM-XRA-1294)

The production F4U-1 Corsair had a length of 33 feet, 4.125 inches (10.163 meters), wingspan of 40 feet, 11.726 inches (12.490 meters) and overall height (to top of propeller arc) of 15 feet, 0.21 inches (4.577 meters). The wing had 2° incidence at the root. The outer wing had a dihedral of 8.5°, and the leading edges were swept back 4°10′. With its wings folded, the width of the F4U-1 was 17 feet, 0.61 inches (5.197 meters), and gave it a maximum height of 16 feet, 2.3 inches (4.935 meters). When parked, the Corsair’s 13 foot, 4 inch (4.064 meter) propeller had 2 feet, 1.93 inches (65.862 centimeters) ground clearance, but with the fighter’s thrust line level, this decreased to just 9.1 inches (23.1 centimeters).

Vought-Sikorsky F4U-1 Corsair, 1942. (U.S. Navy)

During fight testing of a production F4U-1 Corsair with a Pratt & Whitney R-2800-8 (Double Wasp SSB2-G) engine installed, armed with machine guns with 360 rounds of ammunition per gun, the fighter reached a maximum speed of 395 miles per hour (635.7 kilometers per hour) in level flight at 22,800 feet (6,949 meters), using Military Power. The service ceiling was 38,400 feet (11,704 meters).

A total of 12,571 Corsairs were manufactured the Vought-Sikorsky Aircraft Division (F4U-1), Goodyear Aircraft Corporation (FG-1D) and Brewster Aeronautical Corporation (F3A-1). The Corsair served the U.S. Navy and Marine Corps in World War II and the Korean War. Corsairs also served in other countries’ armed forces. Its last known use in combat was in Central America in 1969.

Vought-Sikorsky F4U-1 Corsair, 1942. (U.S. Navy)

¹ corsair: noun, cor-sair. A pirate, or privateer (especially along the Barbary Coast of the Mediterranean Sea); a fast ship used for piracy.

© 2018, Bryan R. Swopes

28 May 1935

Bayerische Flugzeugwerke Bf 109 V1, D-IABI, Werk-Nr. 758, with engine running. (National Air and Space Museum)

28 May 1935: Bayerische Flugzeugwerke Aktiengesellschaft (BFW) test pilot Hans-Dietrich Knoetzsch took the prototype Bf 109 V1 fighter, civil registration D-IABI, on its first flight at Haunstetten, near Augsburg, Germany. The duration of the flight was twenty minutes.

The new fighter was designed by Wilhelm Emil Messerschmitt, Walter Rethel and Robert Lusser. It was a light weight, single-seat, single-engine, low-wing monoplane with retractable landing gear.

BKW Bf 109 V! D-IABI prototype, left profile. (National Air and Space Museum)
BFW Bf 109 V1 D-IABI prototype, left profile. (National Air and Space Museum)

The first prototype, Versuchsflugzeug 1, was 8.884 meters (29.147 feet) long with a wingspan of 9.890 meters (32.448 feet). The empty weight was 1,404 kilograms (3,095 pounds) and the maximum weight was 1,800 kilograms (3,968 pounds).

Because the Junkers Jumo 210 inverted V-12 engines planned for the new fighter were not yet available, a liquid-cooled, supercharged, 1,295.91-cubic-inch-displacement (21.24 liter) Rolls-Royce Kestrel VI single overhead cam (SOHC) 60° V-12 was installed. This British engine had four valves per cylinder and a compression ratio of 6.00:1. It produced 695 horsepower at 2,500 r.p.m., and turned a two-bladed, fixed-pitch Propellerwerk Gustav Schwarz laminated composite propeller through a 0.553:1 gear reduction. The Kestrel was 6 feet, 0.35 inches (1.838 meters) long, 2 feet, 11.00 inches (0.889 meters) high and 2 feet, 0.40 inches (0.620 meters) wide. It weighed 955 pounds (433 kilograms).

This photograph shows teh two-bladed wooden Schwarz propeller installed on D-IAGI. The position of the exhaust ports high on teh engine cowling indicated the use of a Rolls-Royce Kestrel V-12 engine. (National Air and Space Museum)
This photograph shows the two-bladed laminated composite Schwarz propeller installed on D-IAGI. The position of the exhaust ports high on the engine cowling and the large radiator intake indicate the use of the Rolls-Royce Kestrel V-12 engine. (National Air and Space Museum)

V1’s maximum airspeed was 470 kilometers per hour (292 miles per hour) and its maximum altitude was 8,000 meters (26,247 feet).

No armament was installed on the prototype.

The Bf 109 V1 was tested for several months before being sent to the Luftwaffe test center at Rechlin for acceptance trials. The prototype’s landing gear collapsed while landing there.

Bf 109 V1 D-IABI after the landing gear collapsed at Rechlin. (National Air and Space Museum).
Bf 109 V1 D-IABI after the landing gear collapsed at Rechlin. (National Air and Space Museum).

The prototype Bf 109 was revealed to the public when D-IABI flew at the Games of the XI Olympiad (the 1936 Summer Olympics, held at Berlin, Germany).

The Bf 109 (also known as the Me 109, following Willy Messerschmitt’s acquisition of BFW) was produced from 1937 to 1945. Total production was 33,894 aircraft, which amounted to 57% of total fighter production for Germany. Seven plants produced the Bf 109 during World War II.

After the war ended, Czechoslovakia produced a variant until 1948. Another Spanish-built variant remained in production until 1958.

This recently-restored Messerschmitt Bf 109G-4 is a very fine example ofthe World War II German fighter. (© Photoz by Liza. Image courtesy of Liza Eckardt)
This Messerschmitt Bf 109G-4 was recently restored by the Fighter Factory, Virginia Beach, Virginia. It is a very fine example of the classic World War II German fighter. (Image courtesy of Liza Eckardt © Photoz by Liza)

© 2018, Bryan R. Swopes

26 May 1942

Northrop Corporation XP-61 Black Widow at Hawthorne.
Northrop Corporation XP-61 prototype 41-19509 at Northrop Field, 1942. (U.S. Air Force)

26 May 1942: The prototype Northrop XP-61-NO Black Widow, 41-19509, made its first flight at Northrop Field, Hawthorne, California, with free-lance test pilot Vance Breese at the controls. (Breese had taken the North American Aviation NA-73X, prototype of the Mustang, for its first flight, 20 October 1940.)

Northrop XP-61 41-19509 taking off from Northrop Field. (U.S. Air Force)

The first American airplane designed specifically as a night fighter, the XP-61 was the same size as a medium bomber: 48 feet, 11.2 inches (14.915 meters) long with a wingspan of 66 feet (20.117 meters) and overall height of 14 feet, 8.2 inches (4.475 meters). The prototype was equipped with a mockup of the top turret. Its empty weight was 22,392 pounds (10,157 kilograms), gross weight of 25,150 pounds (11,408 kilograms) and maximum takeoff weight of 29,673 pounds (13,459 kilograms).

Northrop XP-61 41-19509 retracts its landing gear after takeoff. (U.S. Air Force)

The XP-61 was powered by two air-cooled, supercharged, 2,804.4-cubic-inch-displacement (45.956 liter) Pratt & Whitney Double Wasp SSB2-G (R-2800-10) two-row, 18-cylinder radial engines with a compression ratio of 6.65:1. The R-2800-10 had a Normal Power rating of 1,550 horsepower at 2,550 r.p.m. at 21,500 feet (6,553 meters), and 2,000 horsepower at 2,700 r.p.m. for takeoff, burning 100-octane gasoline. The R-2800-10 had a 2:1 gear reduction and drove four-bladed Curtiss Electric constant-speed propellers which had a 12 foot, 2 inch (3.708 meter) diameter. The R-2800-10 was 4 feet, 4.50 inches (1.334 meters) in diameter, 7 feet, 4.47 inches (2.247 meters) long, and weighed 2,480 pounds (1,125 kilograms), each.

The prototype Black Widow had a top speed of 370 miles per hour (595 kilometers per hour) at 29,900 feet (9,114 meters) and a service ceiling of 33,100 feet (10,089 meters). The maximum range was 1,450 miles (2,334 kilometers).

Prototype Northrop XP-61 Black Widow 41-19509 in camouflage. (U.S. Air Force)

The night fighter was crewed by a pilot, a gunner and a radar operator. A large Bell Laboratories-developed, Western Electric-built SCR-720 air search radar was mounted in the airplane’s nose. The gunner sat above and behind the pilot and the radar operator was in the rear fuselage.

SCR-720 Air Search Radar mounted in nose of a Northrop P-61 Black Widow night fighter. (NOAA)

The Black Widow was armed with four Browning AN-M2 .50-caliber machine guns in a remotely-operated upper turret, and four AN-M2 20 mm aircraft automatic cannons, grouped close together in the lower fuselage and aimed directly ahead. This was a superior arrangement to the convergent aiming required for guns mounted in the wings. The fire control system was similar to that used by the B-29 Superfortress. The guns could be fired by either the gunner or the radar operator. The Black Widow carried 200 rounds of ammunition for each cannon,

Northrop P-61A-1-NO Black Widow 42-5507 in olive green camouflage. (U.S. Air Force)
Northrop P-61A-1-NO Black Widow 42-5507 in olive green camouflage. (U.S. Air Force)

The XP-61 was built with a center “gondola” for the crew, radar and weapons, with the engines outboard in a twin-boom configuration, similar the the Lockheed P-38 Lightning. The Black Widow did not use ailerons. Instead, it had spoilers mounted on the upper wing surface outboard of the engines. Roll control was achieved by raising a spoiler, decreasing lift on that wing and causing it to drop. A similar system was employed on the Boeing B-52 Stratofortress ten years later.

Northrop P-61A three-view illustration with dimensions. (U.S. Army Air Forces)

The P-61 got its nickname, Black Widow, from the glossy black paint scheme that scientists at the Massachusetts Institute of Technology (M.I.T.) had determined was the best camouflage for a night fighter. Over 700 P-61s were built, with 36 built as the F-15 photo reconnaissance variant. They served in both the Pacific and European Theaters during World War II, and were also used during the Korean War. After the war, the radar-equipped fighter was used for thunderstorm penetration research.

Northrop P-61C-1-NO Black Widow 43-8353 at the National Museum of the United States Air Force. (U.S. Air Force)
Northrop P-61C-1-NO Black Widow 43-8353 at the National Museum of the United States Air Force. (U.S. Air Force)
Northrop P-61C-1-NO Black Widow 43-8353 at the National Museum of the United States Air Force. (U.S. Air Force)

© 2018, Bryan R. Swopes