1 April 1939

The first prototype Mitsubishi A6M1 Type 0, c/n 201. (Mitsubishi Kokuki K.K.)

1 April 1939: Mitsubishi Kokuki K.K. (Mitsubishi Aircraft Company) Chief Test Pilot Katsuzo Shima made the first flight of the prototype Mitsubishi A6M1 Navy Type 0 ¹ fighter at the Kagamigahara air field (now, Gifu Airbase).

Completed about ten days earlier, at the Mitsubishi Aircraft Company factory at Nagoya on the island of Honshu, the prototype fighter had been disassembled so that it could be transported by road approximately 22 miles (36 kilometers) to the airfield.

Beginning late in the afternoon with taxi tests and a brief “hop” to check control response, at 5:30 p.m., Shima took off on what would be a successful test flight.

The prototype S12, serial number 201, had been designed in response to an Imperial Japanese Navy requirement for a new, light-weight fighter for operation from aircraft carriers. The design team was led by Dr. Jiro Horikoshi, an engineering graduate from the Aviation Laboratory at the University of Tokyo.

The design team for the Mitsubishi A6M1 Type Zero. Dr. Jiro Horikoshi is second from left. His assistant, Yohtoshi Sone is in the center. (Mitsubishi)
The design team for the Mitsubishi A6M1 Type Zero. Dr. Jiro Horikoshi is at the center. His assistant, Yoshitoshi Sone, is at the left. (Mitsubishi Kokuki K.K.)

The Type 0 (best known as the “Zero”) was a single-place, single-engine, low-wing monoplane with retractable landing gear. It was of very light construction, being primarily built of a special aluminum alloy, although its control surfaces were fabric covered. The empty weight of the first prototype was just 1,565.9 kilograms (3,452.2 pounds). Its test weight on 1 April was 1,928 kilograms (4,251 pounds).

The two prototype A6M1s were powered by an air-cooled, supercharged, 28.017 liter (1,709.7 cubic inch displacement) Mitsubishi MK2C Zuisen 13, a two-row, fourteen cylinder radial engine, rated at 780 horsepower for takeoff. The engine initially drove a two-bladed variable pitch propeller, but during testing this was replaced by a three-bladed Sumitomo constant-speed propeller, which was manufactured under license from Hamilton Standard.

The combination of very light weight and relatively low power made the Zero very maneuverable and capable of long distance flights.

After the success of the A6M1’s initial flight tests, a second prototype, c/n 202, was built and testing continued. In September 1939 the Japanese Navy accepted the new fighter, the Rei Shiki Sento Ki, or “Rei-Sen,” and it was ordered into production with few changes.

A Mitsubishi A6M2 Model 21 "Zero" fighter takes off from an aircraft carrier of the Imperial Japanese Navy.
A Mitsubishi A6M2 Model 21 “Zero” fighter takes off from an aircraft carrier of the Imperial Japanese Navy.

The first production model was the A6M2 Type 0 Model 21. The Mitsubishi engine was replaced by a more powerful Nakajima NK1C Sakae 12. The fighter’s wing tips could be folded upward for a slight improvement in storage aboard aircraft carriers.

Sources vary on the exact dimensions of the Zero fighters. The National Naval Aviation Museum at NAS Pensacola, Florida, which has an A6M2 in its collection, gives the airplane’s length as 29 feet, 8.6 inches (9.058 meters). The wingspan is 39 feet, 4.5 inches (12.002 meters), and the height is 10 feet, 0 inches (3.048 meters). It has an empty weight of 1,680 kilograms (3,704 pounds), and loaded weight of 2,796 kilograms (6,164 pounds), about half the weight of its rivals, the Chance Vought F4U Corsair and Grumman F6F Hellcat.

Mitsubisshi A6M3 Model 22 "Zeke" in the Solomon Islands, 1943. (Imperial Japanese Navy)
Petty Officer 1st Class Hiroyoshi Nishizawa, a leading fighter ace of the Imperial Japanese Navy, flying a Mitsubishi A6M3 Type 0 Model 22 in the Solomon Islands, May 1943. (Imperial Japanese Navy)

The A6M2 Type 0 was powered by an air-cooled, supercharged, 27.874 liter (1,700.962 cubic inch) Nakajima Hikoki K.K. NK1C Sakae 12, a two-row, fourteen-cylinder radial engine which was rated at 925 horsepower, and drove a three-bladed Sumitomo constant-speed propeller through a 1.71:1 gear reduction.

The Model 21 had a cruise speed of 207 miles per hour (333 kilometers per hour). Its maximum speed was 277 miles per hour (446 kilometers per hour) at Sea Level and 335 miles per hour (539 kilometers per hour) at 16,000 feet (4,877 meters). The service ceiling was 37,000 feet (11,278 meters) and maximum range, 1,175 miles (1,891 kilometers).

The A6M2’s armament was manufactured by Dai Nihon Heiki K.K. Two Type 97 7.7 mm (.303-caliber) machine guns were mounted on the forward upper fuselage, synchronized and firing through the propeller arc. These were licensed versions of the Vickers Type E .303 machine gun. There were 600 rounds of ammunition per gun. A Type 99 20 mm autocannon was mounted in each wing with 100 shells per gun. The Type 99 was a licensed version of the Oerlikon FF autocannon.

The Mitsubishi A6M Zero was one of the most successful fighters of World War II. Although its light construction made it vulnerable to the heavy machine guns of American fighters, in skilled hands, the highly maneuverable Zero was a deadly opponent.

The Mitsubishi A6M Type 0 was produced from 1940 through 1945. 10,939 Zeros were built. At the end of World War II, almost all of the surviving fighters were destroyed and only a very few remain.

An A6M2 was captured near Dutch Harbor in the Aleutian Islands in June 1942. Known as the “Akutan Zero,” the fighter was extensively tested by the U.S. Navy and the National Advisory Committee for Aeronautics (NACA) at NAS Anacostia. Under extreme secrecy, the airplane was also tested in the Full Scale Wind Tunnel at NACA’s Langley Memorial Aeronautical Laboratory at Hampton, Virginia.

Lieutenant Commander Eddie Sanders, United States Navy, taxis a captured Mitsubishi A6M2 Navy Type 0 Model 21 “Zero” at NAS San Diego, California, circa September 1942. (U.S. Navy)
Mitsubishi A6M2 Navy Type 0 Model 21 fighter at NACA Langley Memorial Aeronautical Laboratory, 8 March 1943. (NASA)
Mitsubishi A6M2 Navy Type 0 Model 21 fighter at NACA Langley Memorial Aeronautical Laboratory, 8 March 1943. (NASA)
A captured Mitsubishi A6M2 Navy Type 0 Model 21 fighter during flight testing in the United States, circa 1942–1943. (U.S. Navy)
Mitsubishi A6M2 Navy Type 0 Model 21 (U.S. Navy)

¹ The 0 (the numeral zero) in the fighter’s type designation refers to the the final digit of the year 2600 of the Imperial Japanese Calendar, which was 1940 AD by the Gregorian calendar. This gave the A6M2 its most common identification, simply, “the Zero.”

© 2019 Bryan R. Swopes

1 April 1921

Adrienne Bolland, Femme Chevalier de la légion d'honneur. (1895–1975)
Adrienne Bolland, Femme Chevalier de la légion d’honneur. (1895–1975)

1 April 1921: Adrienne Bolland, a pilot employed by René Caudron to demonstrate his airplanes in South America, flew a Caudron G.3 from Mendoza, Argentina to Santiago, Chile, across the Andes Mountain Range.

Mlle Bolland’s route followed the Paso de Upsallata, passing south of Aconcagua, at 6,960.8 meters (22,837 feet), the highest mountain in the Andes, and north of Volcan Tupangato, 6,570 meters (21,580 feet). The duration of the flight was 4 hours, 17 minutes.

Adrienne Bolland is greeted on her arrival at Santaigo, Chile, 1 April 1921.
Adrienne Bolland is greeted on her arrival at Santaigo, Chile, 1 April 1921. 

Bolland was awarded a gold medal by the Argentine League of Patriots at Buenos Aires.

FLIGHT reported:

Mdlle. Bolland Crosses the Andes

From a Daily Mail report Mdlle. Bolland, the French aviatress, on April 1, left Mendoza, Argentina, at 7.30, and flew over the Andes Mountains, arriving at Santiago in Chile, just three hours later.

This the second time Mdlle. Bolland has flown over the Andes.

The distance Mdlle. Bolland covered was about 112 miles. There are heights of more than 20,000 ft. in the neighborhood of the point at which she crossed the range.

We are just wondering whether the journey was a “non-stop” one, with strong headwinds, or whether a halt was made en route, and if the latter, where.

FLIGHT The Aircraft Engineer and Airships, No. 641 (No. 14, Vol. XIII.), 7 April 1921, at Page 250, Column 2

Satellite image of the Andes Mountains in the region crossed by Adrienne Bolland. Her departure point, Mendoza, Argentina, is at the upper right edge of the image. The Upsallata Pass is in the upper center area, with Aconcagua near the top of the image, just left of center. Bolland’s destination, Santiago, Chile, is in the lower left corner. (Google Maps)

Adrienne Armande Pauline Boland was born at Arcueil, a suburb of Paris, France, 25 November 1895. She was the youngest of seven children of writer Henri André Joseph Boland and Marie Amélie Elisabeth Françoise Allonie (Marie Joséphine) Pasques. Her father died in 1909, and her mother sometime later.

At the age of 24, she decided to learn to fly and enrolled in flight training at Société des Avions Caudron (the Caudron Airplane Company), Le Crotoy. She started training 16 November 1919 and was awarded her pilot’s license 29 January 1920. An error on the certificate spelled her surname with two “l”s, and she retained the name “Bolland” for the rest of her life.

Chilean dignataries congratulate Adrienne Bolland at Santiago, Chile, 1 April 1921.
Chilean dignataries congratulate Adrienne Bolland at Santiago, Chile, 1 April 1921.

Mlle Bolland was employed by René Caudron to transport airplanes to and from the factory. She told Caudron that she wanted her own airplane. He told her that if she could perform a loop in a Caudron G.3, a pre-World War I scout plane, that she could fly it for the company. She did, and was then asked to fly it across the English Channel, which she did, 25 August 1920.

Adrienne Bolland flew this Caudron G-3 from Mendoza, Argentina to Santiago, Chile, 1 April 1921.
Adrienne Bolland flew this Caudron G.3, F-ABEW, c/n 4902, from Mendoza, Argentina to Santiago, Chile, 1 April 1921.

Caudron sent her to Argentina to demonstrate his airplanes. Once there, she planned to fly across the Cordillera de los Andes (the Andes Mountain Range) to Chile on the western coast of South America. The mountains were higher than the airplane was capable of flying, so she had to fly through valleys to find a way across. Departing Mendoza, Argentina at 6:00 a.m, she headed across the 400-kilometer (250 miles) wide mountain range. Most of the flight was at an altitude of 4,500 meters (14,764 feet) and it was extremely cold. Without maps, she succeeded: “Suddenly I saw a break in the mountains. . . and in the distance, the plain of Chile. I was saved.”

Adrienne Bolland with her Caudron G.3, 19 May 1921. (Air France)
Adrienne Bolland with a Caudron G.3, 19 May 1921. (Air France)

The airplane was sold in Santiago and Bolland returned to Buenos Aires by train.

After returning to France, Mlle Bolland was a frequent participant at air meets, displaying her skills in aerobatics. She flew two Caudron C.27s, G-AGAP (c/n 5533.7) and F-AGAQ (c/n 5534.8), both registered in her name 27 February 1924. At the Aérodrome d’Orly, Paris, on 27 May 1924, she took off at 4:12 p.m., completed 212 consecutive loops, then landed at 5:25 p.m. (The Caudron C.27 was redesignated C.127 in late 1924.)

Adrienne Bolland with her Caudron C.27, F-AGAQ (c/n 5534.8). (Unattributed)

In 1924, France named Adrienne Bolland Chevalier de la légion d’honneur for her flight across the Andes.

Ernest Jean Baptiste Charles Vinchon married Mlle Bolland in Paris, 15 March 1930.

After the surrender of France to Nazi Germany in 1940, M. and Mme Vinchon remained in occupied France and became agents of the Confrérie Notre-Dame (CND, or Brotherhood of Notre Dame, later called CND-Castile), an intelligence organization of the Forces françaises libres (Free French Forces).

For her services during World War II, in 1947 Mme Vinchon was advanced to the rank of Officier de la Légion d’honneur.

Adrienne Bolland Vinchon died at Paris, France, 18 March 1975 at the age of 79 years. She was buried in Donnery, Loiret.

Caudron G.3 (Musée de l’Air et de l’Espace)

Adrienne Bolland crossed the Andes in a Caudron G.3, c/n 4902, registered F-ABEW. The Caudron G.3 was a World War I reconnaissance airplane and flight trainer manufactured by Société des Avions Caudron. It is called a sesquiplane because the lower wing is significantly shorter than the upper. The G.3 was a single-engine aircraft that was built in single- and two-place variants. The engine and cockpit are contained in a very short fuselage, supporting the wings and landing gear. Tail control surfaces are mounted on an open framework tail boom.

The Caudron G.3 was 6,40 meters (20 feet, 11.6 inches) long with an upper wingspan of 13,40 meters (43 feet, 11.6 inches). The height of the aircraft was 2,60 meters (8 feet, 6.6 inches). The G.3 had an empty weight of 355 kilograms (783 pounds) and maximum gross weight of 630 kilograms (1,389 pounds).

Caudron G.3 two-view illustration. (Jane’s All the World’s Aircraft,at Page 87. Published 1913 by Fred T. Jane)

The G.3 was powered by an air-cooled, normally-aspirated 10.910 liter (665.791 cubic inches) Société des Moteurs Gnome et Rhône 9C nine-cylinder rotary engine with a compression ratio of 5:1. It was rated at 70 cheval vapeur (1 ch = 0.99 horsepower) at 1,100 r.p.m., and 80 cheval vapeur  at 1,200 r.p.m., but able to produce a maximum 92 cheval vapeur (90.77 horsepower) at 1,300 r.p.m. It drove a two-bladed, fixed-pitch wooden propeller. The 9C was 0.810 meters (2 feet, 7.9 inches) long, 0.930 meters (3 feet, 6.1 inches) in diameter and weighed 119 kilograms (262 pounds).

The Caudron G.3 had a cruising speed of 80 kilometers per hour (50 miles per hour) maximum speed of 95 kilometers per hour (59 miles per hour) at 100 meters (328 feet) and service ceiling of 4,300 meters (14,108 feet).

On 1 April 1921 in Santiago, French pilot Adrienne BOLLAND on board her Caudron G-3 after she succeeded in crossing the Andes. It is a signed photo: the pilot's signature is at the centre. (Getty Images/Keystone France)
“On 1 April 1921 in Santiago, French pilot Adrienne BOLLAND on board her Caudron G-3 after she succeeded in crossing the Andes. It is a signed photo: the pilot’s signature is at the centre.” (Getty Images/Keystone-France)
Aconcagua viewed from the south. (Bjørn Christian Tørrissen, via Wikipedia)
Tupungato, a 21,560-foot (6,570 meters) strato volcano, located just to the east of the Argentina/Chile border. On 2 August 1947, the British South American Airways Avro Lancastrian, R.M.A. Star Dust, crashed into the eastern slope at the 15,000 foot (4,572 meters) level. The wreck was buried by an avalanche and was discovered in 1998. The peak at the upper right may be Cerro Mercedario, 22,050 feet (6,620 meters).(Diode via Wikipedia)

© 2018, Bryan R. Swopes