Compiled by:- Michael Debattista
The agility of this World War II fighter aircraft can best be summed up by a quote from a Japanese fighter pilot who flew the type during the war," The Zero was to me what the sword was to the Samurai. I can manoeuvre the Zero just as if it were my body". A very agile craft, perhaps the most agile fighter of World War II, the Zero proved itself very successful against Allied air forces during the months of 1941 and 1942 in the Pacific war theatre. However, in the latter half of the war, with the introduction by the Allies of newer and better fighters as well as better tactics the Zero was swept from the skies. By 1944, the once mighty Zero became obsolete yet it still soldiered on till the end of the war.
The origins of this fighter lay in an Imperial Japanese Navy requirement, issued during the latter half of 1930s, for a Type 0 naval fighter thereby replacing the Mitsubishi A5M "Claude" which was then in service. The response from the Mitsubishi design team, led by Jiro Horikoshi was a monoplane that had a cantilever low-wing layout, having an enclosed cockpit and a retractable landing gear as well as being constructed almost entirely of metal. Powered by a 780-hp Mitsubishi MK2 Zuisei engine, the A6M1 prototype flew for the first time on 1st April 1939 and a second prototype, which was powered by a similar engine, was flown in October 1939. The prototypes submitted by Mitsubishi proved themselves slower than those of its competitors yet they clearly had superior manoeuvrability. In the event, the Imperial Japanese Navy selected the Mitsubishi design for production indicating the prevalent philosophy of Japanese military aviation at the time that what mattered most in a fighter was agility over performance. Nevertheless, the Japanese navy suggested the design should incorporate the more powerful 925-hp Nakajima NK1C Sakae radial engine. Despite the fact that the engine was somewhat heavier and larger than the powerplants of the earlier prototypes, this was successfully incorporated into the modified airframe. The resultant machine, the A6M2 prototype, flew for the first time on 18 January 1940. Extensive service trials by this and the fourth prototype proved very successful and on the 21 July 1940 the Imperial Japanese Navy requested Mitsubishi to supply 15 pre-production A6M2 models for combat evaluation over China.
Over China, the Zeros effectively proved their worth. Despite their small numbers, they were used extensively and effectively made their presence felt. When the first production aircraft became available, they were sent to China to bolster Japan's war effort there. The mighty Zeros managed to shoot down a large number of enemy aircraft while suffering only losses of two of their own numbers to ground fire. So effective was the Zero that the head of the American Volunteer Group Claire Chennault sent a report to USAAF headquarters outlining the Zero's potential. Surprisingly and as it turned out, foolishly, this report was ignored. As a matter of fact the Allies expected that, should a war break out against Japan, their air forces expected that Japan will be fielding obsolete warplanes against them. The presence of aircraft like the Ki-43 Oscar and the Mitsubishi A6M came as a disagreeable surprise to the Allies when war broke out.
Meanwhile in Japan, the production of the A6M2 model was in full swing. The Mitsubishi company, supplemented by the Nakijama company's Koizuma factory, had produced no less than 400 A6M2 by the time of Japan's attack on Pearl Harbour on 7th December 1941. These included the A6M2 Model II (which had Nakajima NK1C Sakae 12 powerplant and its armament comprising of two wing-mounted Type 99 20mm cannon and a couple of 7.7mm machine-guns in the forward fuselage) and the similar A6M2 model 22 which had a manually-folding wingtips in order to facilitate carrier stowage.
In the opening months of the war in the Pacific, the Zero dominated the skies, wiping off any opposition came up against. Most of the Allied fighters based in the Pacific proved to be no match of this supremely agile Japanese menace. Fighter planes like the Brewster Buffaloes were sitting ducks since they neither had the speed nor the agility to combat it. The Supermarine Spitfire was a rarity in the Pacific theatre at the outbreak of war against Japan since they were sorely elsewhere. In the case of the Americans, the Curtiss P-40 and the Grumann F4F Wildcat could not fight the Zero on equal terms: their agility was no match for a well-handled Zero however they had an edge over the Zero in speed, armament and ability to absorb punishment.
The Zero was certainly agile and it had a phenomenal range especially when a drop-tank was fitted, thanks to its propeller mechanism. It was well armed for its days and was certainly better armed than its compatriots at the outbreak of war: the Ki-27 "Nate" and the Ki-43 "Oscar" were armed with just a couple of machine-guns! However, it had its own flaws. When the speed of the aircraft exceeded 250mph, the Zero lost much of its agility owing to certain control surfaces were fabric-covered. If a Zero was subjected to a prolonged dive, there was the risk of shedding its wings in the process: this problem was addressed with the introduction of the A6M5 variant. The biggest flaws though were the lack of self-sealing fuel tanks and lack of armour in order to protect its pilot. This meant that a well-aimed burst from a relatively heavily- armed aircraft will easily turn a Zero into a blazing torch!
An A6M2 variant: this particular aircraft was used in the attack on Pearl Harbour and belonged to the aircraft carrier Hiryu
A floatplane version of the Zero also existed: essentially this was an A6M2 variant fitted out with floats instead of wheels. This version, known as the A6M2-N and nicknamed "Rufe" by the Allies, was built by Nakajima. The scope behind it was to use such fighter in amphibious operations where there would be no airfields available in the vicinity of the Japanese forces. This variant had a large central float, which also housed an auxiliary fuel tank and two smaller stabilising floats beneath the wings. This aircraft was extensively used throughout 1942/ early 1943 where it was found out while this aircraft retained a good measure of manoeuvrability, it was inferior in speed and consequently no match for Allied fighters.
In spring of 1942, another variant was introduced in the war scene: the A6M3 model. This variant had clipped wings, dispensing with the manual folding wingtip feature and the uprated Nakajima Sakae 21 engine which had an output of 1,130 hp (843 kW). The resulting aircraft was faster than the A6M2 but having an inferior range owing to higher fuel consumption by the uprated engine. The later variant of the A6M3, namely A6M3 model 22, re-incorporated the manual folding wingtip.
By mid-1942, the tide was clearly turning against the Japanese. New aircraft such as the P-38 Lightning, F6F Hellcat and the F4U Corsair were beating the once-mighty Zero from the sky. New tactics, which were evolved in order to beat the Zero also helped (such as the "Thatch Weave"). In the meantime, Mitsubishi was producing the A6M5 variant. This variant was built as a response to the threat imposed by the new breed of Allied fighters that were seriously challenging Japanese air superiority and also owing to Mitsubishi's failure to produce a fighter that would effectively replace the Zero namely the A7M Reppu (Thunderbolt). Furthermore, the A6M4 variant failed to enter production owing to teething problems in the development of the experimental turbocharged Sakae engine: only two A6M4 prototypes were produced.
An A6M2 model of the Mitsubishi Zero
The A6M5 was the most prolific variant: as a matter of fact it was built in quantity far greater than any other Japanese combat aircraft: however it incorporated little effective improvement over its predecessors. Basically, this variant retained the Sakae 21 engine, featured clipped non-folding wings with rounded wingtips and also introduced individual exhaust ejectors in order to give some thrust augmentation to the aircraft. Quite a number of sub-variants were also developed:
Ø The A6M5a featured a modification in the wings in order accept belt-fed cannons instead of the magazine-fed ones,
Ø The A6M5b featured armoured glass in the cockpit canopy besides a minor change in the armament configuration (incorporation of one 7.7 mm machine gun, one 13.2 mm machine gun and two 20mm cannons instead of two 7.7 mm machine guns and two 20 mm cannons),
Ø The A6M5c incorporated three 13.2 mm machine guns and 20 mm cannons
Ø The A6M5d-S was a night fighter which incorporated a 20 mm cannon mounted obliquely in the rear fuselage foe use against bombers, and
Ø A trainer variant, the A6M5-K
During 1944, development of the Zero continued with the conversion of the A6M5 airframes to A6M6 standard by the incorporation of the much awaited Sakae 31 engine with a water-methanol injection, boosting the aircraft's maximum speed to 345mph. In late 1944, the A6M6c began to enter service: this variant incorporated (as standard fitting) self-sealing fuel tanks rectifying therefore to some extent one of its most fatal flaws of the Zero: its tendency to easily catch fire when hit. This variant also introduced some field conversions, principally modifications in order to enable the Zero to carry a 250kg bomb in the centreline (instead of the drop-tank). The A6M7 was a similar variant: it was specifically used as a Kamikaze weapon and incorporated some structural reinforcement for such one-way trip mission.
The final variant, the A6M8c was an attempt by Mitsubishi to extend the capabilities of the Zero, which by 1945 was already obsolete. It incorporated the powerful 1560hp Mitsubishi MK8P Kinsei 62 radial engine. Tests revealed this aircraft as a formidable machine and some 6,300 machines were ordered. However, only a handful were built owing to the chaotic state of the Japanese industry due to the US strategic bombing.
By 1945, the Mitsubishi Zero, along with several compatriots like the Ki-43 Oscar were clearly obsolete. Such aircraft were easily shot down in droves by the superior Allied aircraft. As if the problems for Japan weren't enough, Japan was facing an acute shortage in pilots and was fighting an enemy that was superior in both equipment, pilot quality and an enemy who seemed to have an endless supply of resources. Worse than it was, many of the Japanese aces were dead and the few pilots that the Japanese fielded were mostly raw recruits that were no match for any Allied opponent they encountered. However, some few Japanese pilots managed to fight on against impossible odds. A case in point was Saburo Sakai, one of the best known Japanese aces. On one day in 1945 he was bounced on by no less than 12 Hellcats. Clearly he was at a great disadvantage: not only the Hellcat was far more superior than the Zero that Saburi was flying but also he was far outnumbered! However, he managed to evade his opponents by using the Zero's superior manoeuvrability and managed to make his way back to Iwo Jima without being hit by a single bullet!
References:
Axis Aircraft of World war II by David Mondey
The illustrated directory of Fighting Aircraft of World War II by Bill Gunston
The internet (as regarding to the pictures)
