The Mitsubishi A6M5 Reisen
The prime contractor for the A6M5 Reisen (Allied code name Zeke a.k.a. Zero) was the Mitsubishi Jukogyo K.K. Corporation in Nagoya, Japan who co-manufactured the aeroplane with Nakajima for the Imperial Navy. This design was still secret in 1937. It used an American designed cowl, which surrounded the engine & provided a limited amount of streamlining. But it derived its speed & manoeuvrability from its lightweight. The weight reduction came at a price because Zero pilots were not provided with armoured protection. In contrast most others fighters would have used a heavy metal shield against enemy bullets. Other features were also sacrificed like self sealing fuel tanks which would have provided added safety but increased the aircraft’s weight. These omissions were made not out of any disregard for Japanese fighter pilots. Rather it was a pragmatic formula to give the A6M speed & agility. These protective devices weighed hundreds of kilograms and could not be incorporated if Mitsubishi hoped to meet the performance requirements specified by the Imperial Navy. Yet the lack of these components eventually became the Zeros undoing. Speed & agility alone were expected to increase the pilot’s chances of survival & at the same time produce a much more effective weapon. There is no doubt that the Zeros formula was successful & it did demonstrate that with some improvisation it was possible to use radial engines & still obtain high speed. The question was how could you do this in an all-metal aircraft with modern safety features.
Japanese naval aviators flew 328 combat-ready A6M2 Reisens against American forces at Pearl Harbour and in the Philippines. The Reisen totally outclassed all Allied fighter aircraft for the first six months of the war until American carrier forces stopped the Japanese in the Coral Sea and at Midway in May and June 1942. The loss of four Japanese aircraft carriers at Midway underscored a deadly trend. The Japanese were losing experienced pilots and aircraft faster than they could replace them. Yet for almost two more years the ZEKE, as the Allies code-named it, remained an ominous threat.
The Reisen was considerably lighter than American fighters. It could climb faster and out-manoeuvre them in close combat or 'dog fighting.' But as combat experience mounted and training improved, the American tactics began to change. U. S. Navy and Army pilots avoided the turning and looping dogfight and began to engage the Zeros only when they could surprise the Japanese pilots by attacking with a height or speed advantage. This type of attack consisted of a single, straight pass with guns blazing. The American pilot then continued away from the Zero using his superior speed to zoom to safety or circle around at a distance and attack again. This idea and other tactics transformed pilots flying the Grumman F4F Wildcat (once considered totally obsolete against the Zero) into formidable opponents more than capable of destroying the Japanese fighter.
The Allies began fielding aircraft superior to the Zero in 1942. Lockheed chief designer, Kelly Johnson (who also designed the SR-71 Blackbird), crafted the aeroplane that eventually destroyed more Japanese aircraft than any other, the Lockheed P-38 Lightning. U. S. Army Air Force's Lightning pilots downed the first Zeros late in 1942, using their superior speed and climbing performance. The F6F-3 Hellcat entered combat in August 1943 and the Pratt & Whitney R-2800 engine that propelled it also gave the Hellcat pilot enough speed and climb to engage or avoid the Zero without regard for the tactical situation.
Japan's aviation industry continued to develop advanced fighters but the complex process of perfecting and fielding these new aeroplanes was beset by a number of problems and only limited numbers saw action. Consequently, the Zero remained in production throughout the war. Between March 1939 and August 1945 the Japanese built a total of 11,291 Zeros (with 6,215 examples of the Mitsubishi design actually being produced under license by Nakajima) and sub-variants related to it, more than any other Japanese warplane.