Mitsubishi A6M2b Type Zero Carrier Fighter Model 21 Rei-sen “Zero”

“The Zero excited me as nothing else had ever done. Even on the ground it had the cleanest lines I had ever seen in an aeroplane. it was a dream to fly.”

— Sub-Lieutenant Saburō Sakai

(坂井 三郎 )

was a Japanese naval aviator and flying ace (撃墜王) of the Imperial Japanese Navy during World War II.



Maneuverability – Nothing can outturn a Zero, horizontally, vertically or any combination.

Range – With judicious use of the throttle, the Zero can fly to any target on any map in the game.



Durability – The complete lack of pilot and fuel protection makes that the Zero the easiest plane in the game to bring down.


With the A5M Claude just starting to enter service the Japanese Navy decided to task the nation’s aircraft manufacturers with designing and building a superior replacement. Looking for a “state of the art” airplane that would exceed the performance of anything it was likely to meet, the Navy established stringent performance criteria. The new design had to be capable of a top speed of 310 mph and had to climb to 10,000 feet in 3 1/2 minutes. Armed with two cannons and two machine guns and having a range exceeding that of any current fighter, it had to be equal to or better than the Claude in maneuverability and handling. Nakajima immediately withdrew from the competition, stating that it was impossible to design such a plane. But Mitsubishi’s Jiro Hirokoshi felt that it could be done and set about the task of designing the plane.The team selected the company’s own 780 hp Zuisei 13 fourteen-cylinder radial engine, partly because it was a Mitsubishi product, but mostly because of its small diameter and light weight. Special attention was paid to weight reduction with the plane utilizing the new Extra-Super Duralumin alloy developed for aircraft use by the Sumitoma Metal Industry Company. To simplify production and maintenance, the single spar wing and center fuselage section were built as a single piece and the front and rear portions of the fuselage were removable.

The first prototype was flown on April 1, 1939 and proved an immediate success with only a few minor problems, including a tenancy to vibrate excessively. After further testing and experimentation the two-blade prop was replaced with a constant-speed, three-blade propeller, which eliminated almost all of the vibration in the plane. The Navy accepted the first prototype for testing on September 14, 1939 as the A6M1 Type 0 Carrier Fighter, which in Japanese is Rei Shiki Sento Ki and was shortened to Rei-sen, literally “Zero Fighter”. This prototype would end up making 119 flights with a total flight time of 43 hours 26 minutes!

Meanwhile, the Navy had accepted Nakajima’s new 925 hp Sakae 12 engine into service. With its similar dimensions and weight to the Zuisei, the Navy ordered Mitsubishi to install the new engine on the third prototype, which was given the designation A6M2 to distinguish it from the Zuisei powered model. Flight tests of the A6M2 began on January 18, 1940, the additional power of the engine allowing the plane to far exceed the rigid performance specifications laid out by the Navy and so fifteen machines were ordered for use in Service Trials in China.

The 12th Kokutai stationed in Hankow received the new A6M2s and immediately used them on their first combat mission on August 19, 1940. However, they saw no action until their fourth mission when they encountered a formation of Chinese I-15s and I-16s. They turned and dove into the Chinese formation, shooting down all 27 enemy planes without suffering a single loss. Over the next few months 153 Rei-sen sorties resulted in the destruction of 59 Chinese planes in the air and 101 on the ground, without a single loss. Soon the Chinese Air Force declined to engage Rei-sen escorted bomber formations and the Japanese were allowed to roam at will over the country.

Claire Chenault, then serving as the air commander for the Nationalist Chinese, reported on the ability of this plane, but American commanders ignored the implications and thus the first appearance of the plane to Western forces came as a shock and a surprise. When it did show up, Allied intelligence gave it the code-name ‘Zeke’, but by then everyone knew its Japanese code-name and it was commonly called the ‘Zero’ by Allied troops.

Production of the A6M2 Model 11 had just begun when the wing spar on the second A6M1 failed, causing a fatal crash. As a result the wing spar was redesigned for greater strength and the new wing was incorporated into the production line starting with the 22nd plane. Carrier Trials Testing revealed a problem with the wingspan being too long to safely fit on the elevators, so starting with the 64th production machine the Model 21 was introduced with the outer 20 inches of wingtip able to be manually folded upwards, which allowed sufficient clearance for elevator operations.

By the time of the Pearl Harbor attack, the Navy had 126 Model 21s assigned to carrier duties and another 213 assigned to land-based squadrons. Over the next several months a myth of invincibility surrounded the Zero that masked its shortcomings. However, this was soon to change.

On June 3, 1942 Flight Petty Officer Tadayoshi Koga took off in his brand-new A6M2 Model 21 for a raid on Dutch Harbor in the Aleutians. On the return flight he noticed he had lost too much fuel and decided to land on the small island that had been designated for emergency landings. Unfortunately the ground was soft and his plane flipped over onto its back, breaking his neck and killing him instantly. Several months later an American naval scouting party found the nearly intact plane, recovered it and shipped it back to the US for testing. This testing revealed its limitations and allowed US designers to tailor their designs to counter the Zero and the other light, highly maneuverable fighters the Japanese were fielding at the time.

Francillon, Rene J.; Japanese Aircraft of the Pacific War; Naval Institute Press, Annapolis, MD; 1979.
Green, William; Famous Fighters of the Second World War; Hanover House, Garden City, NY; 1960.
Nohara, Shigeru; A6M Zero In Action; Squadron/Signal Publications, Carrollton, TX; 1983.

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