The Mitsubishi A6M “Zero” is a long-range fighter aircraft, manufactured by Mitsubishi Aircraft Company, a part of Mitsubishi Heavy Industries, and operated by the Imperial Japanese Navy from 1940 to 1945. The A6M was designated as the Mitsubishi Navy Type 0 carrier fighter (rei-shiki-kanjō-sentōki), or the Mitsubishi A6M Rei-sen. The A6M was usually referred to by its pilots as the “Reisen” (zero fighter), “0” being the last digit of the imperial year 2600 (1940) when it entered service with the Imperial Navy. The official Allied reporting name was “Zeke”, although the use of the name “Zero” was later adopted by the Allies as well.
When it was introduced early in World War II, the Zero was considered the most capable carrier-based fighter in the world, combining excellent maneuverability and very long range. The Imperial Japanese Navy Air Service (IJNAS) also frequently used it as a land-based fighter.
In early combat operations, the Zero gained a legendary reputation as a dogfighter, achieving an outstanding kill ratio of 12 to 1, but by mid-1942 a combination of new tactics and the introduction of better equipment enabled Allied pilots to engage the Zero on generally equal terms. By 1943, inherent design weaknesses and the failure to develop more powerful aircraft engines meant that the Zero became less effective against newer Allied fighters, which possessed greater firepower, armour, and speed, and approached the Zero’s maneuverability. Although the Mitsubishi A6M was outdated by 1944, design delays and production difficulties of newer Japanese aircraft types meant that it continued to serve in a front line role until the end of the war. During the final year of the war in the Pacific, the Zero was also adapted for use in kamikaze operations. During the course of the war, Japan produced more Zeros than any other model of combat aircraft.
The Mitsubishi A5M fighter was just entering service in early 1937, when the Imperial Japanese Navy started looking for its eventual replacement. On October 5th, 1937, they issued “Planning Requirements for the Prototype 12-shi Carrier-based Fighter”, sending it to Nakajima and Mitsubishi. Both firms started preliminary design work while they awaited more definitive requirements to be handed over in a few months.Based on the experiences of the A5M in China, the IJN sent out updated requirements in October calling for a speed of 600 km/h (370 mph) and a climb to 3,000 m (9,800 ft) in 3.5 minutes. With drop tanks, they wanted an endurance of two hours at normal power, or six to eight hours at economical cruising speed. Armament was to consist of two 20 mm cannons, two 7.7 mm (.303 in) machine guns and two 30 kg (66 lb) or 60 kg (130 lb) bombs. A complete radio set was to be mounted in all aircraft, along with a radio direction finder for long-range navigation. The maneuverability was to be at least equal to that of the A5M, while the wingspan had to be less than 12 m (39 ft) to allow for use on aircraft carriers. All this was to be achieved with available engines, a significant design limitation.
Nakajima’s team considered the new requirements unachievable and pulled out of the competition in January. Mitsubishi’s chief designer, Jiro Horikoshi, thought that the requirements could be met, but only if the aircraft were made as light as possible. Every possible weight-saving measure was incorporated into the design. Most of the aircraft was built of a new top-secret aluminium alloy developed by Sumitomo Metal Industries in 1936. Called “extra super duralumin” (ESD), it was lighter, stronger and more ductile than other alloys (e.g. 24S alloy) used at the time, but was prone to corrosive attack, which made it brittle. This detrimental effect was countered with an anti-corrosion coating applied after fabrication. No armour protection was provided for the pilot, engine or other critical points of the aircraft, and self-sealing fuel tanks, which were becoming common at the time, were not used. This made the Zero lighter, more maneuverable, and the longest-ranged single-engine fighter of World War II, which made it capable of searching out an enemy hundreds of kilometres away, bringing them to battle, then returning to its base or aircraft carrier. However, that tradeoff in weight and construction also made it prone to catching fire and exploding when struck by enemy rounds.
With its low-wing cantilever monoplane layout, retractable, wide-set conventional landing gear and enclosed cockpit, the Zero was one of the most modern carrier based aircraft in the world at the time of its introduction. It had a fairly high-lift, low-speed wing with very low wing loading. This, combined with its light weight, resulted in a very low stalling speed of well below 60 kn (110 km/h; 69 mph). This was the main reason for its phenomenal maneuverability, allowing it to out-turn any Allied fighter of the time. Early models were fitted with servo tabs on the ailerons after pilots complained that control forces became too heavy at speeds above 300 kilometres per hour (190 mph). They were discontinued on later models after it was found that the lightened control forces were causing pilots to overstress the wings during vigorous maneuvers.
It has been claimed that the Zero’s design showed a clear influence from British and American fighter aircraft and components exported to Japan in the 1930s, and in particular on the American side, the Vought V-143 fighter. Chance Vought had sold the prototype for this aircraft and its plans to Japan in 1937. Eugene Wilson, president of Vought, claimed that when shown a captured Zero in 1943, he found that “There on the floor was the Vought V 142 or just the spitting image of it, Japanese-made”, while the “power-plant installation was distinctly Chance Vought, the wheel stowage into the wing roots came from Northrop, and the Japanese designers had even copied the Navy inspection stamp from Pratt & Whitney type parts.” While the sale of the V-143 was fully legal, Wilson later acknowledged the conflicts of interest that can arise whenever military technology is exported. Counterclaims maintain that there was no significant relationship between the V-143 (which was an unsuccessful design that had been rejected by the U.S. Army Air Corps and several export customers) and the Zero, with only a superficial similarity in layout.
The Zero resembled the 1937 British Gloster F.5/34. Performance of the Gloster F.5/34 was comparable to that of early model Zeros, with its dimensions and appearance remarkably close to the Zero. Gloster had a relationship with the Japanese between the wars, with Nakajima building the carrier-based plane, the Gloster Gambet, under license. However allegations about the Zero being a copy have been discredited by some authors.
The A6M is usually known as the “Zero” from its Japanese Navy type designation, Type 0 carrier fighter (Rei shiki Kanjō sentōki ), taken from the last digit of the Imperial year 2600 (1940), when it entered service. In Japan, it was unofficially referred to as both Rei-sen and Zero-sen; Japanese pilots most commonly called it Zero-sen, where sen is the first syllable of sentōki, Japanese for “fighter plane”.
In the official designation “A6M”, the “A” signified a carrier-based fighter, “6” meant it was the sixth such model built for the Imperial Navy, and “M” indicated the manufacturer, Mitsubishi.
The official Allied code name was “Zeke”, in keeping with the practice of giving male names to Japanese fighters, female names to bombers, bird names to gliders, and tree names to trainers. “Zeke” was part of the first batch of “hillbilly” code names assigned by Captain Frank T. McCoy of Nashville, Tennessee, (assigned to the Allied Technical Air Intelligence Unit (ATAIU) at Eagle Farm Airport in Australia), who wanted quick, distinctive, easy-to-remember names. When, in 1942, the Allied code for Japanese aircraft was introduced, he logically chose “Zeke” for the “Zero”. Later, two variants of the fighter received their own code names: the Nakajima A6M2-N (floatplane version of the Zero) was called “Rufe” and the A6M3-32 variant was initially called “Hap”. After objections from General “Hap” Arnold, commander of the USAAF, the name was changed to “Hamp”. When captured examples were examined in New Guinea, it was realized it was a variant of the Zero and finally renamed “Zeke 32”.
The first Zeros (pre-series of 15 A6M2) went into operation with the 12th Rengo Kōkūtai in July 1940. On 13th September 1940, the Zeros scored their first air-to-air victories when 13 A6M2s led by Lieutenant Saburo Shindo attacked 27 Soviet-built Polikarpov I-15s and I-16s of the Chinese Nationalist Air Force, shooting down all the fighters without loss to themselves. By the time they were redeployed a year later, the Zeros had shot down 99 Chinese aircraft (266 according to other sources).
At the time of the attack on Pearl Harbor, 521 Zeros were active in the Pacific, 328 in first-line units. The carrier-borne Model 21 was the type encountered by the Americans. Its tremendous range of over 2,600 kilometres (1,600 mi) allowed it to range farther from its carrier than expected, appearing over distant battlefronts and giving Allied commanders the impression that there were several times as many Zeros as actually existed.
( Please check out Flying Tigers previous Newsletter on the 75th Anniversary of the Attack on Pearl Harbor , by clicking the link HERE)
The Zero quickly gained a fearsome reputation. Thanks to a combination of unsurpassed maneuverability — even when compared to other contemporary Axis fighters — and excellent firepower, it easily disposed the motley collection of Allied aircraft sent against it in the Pacific in 1941. It proved a difficult opponent even for the Supermarine Spitfire. “The RAF pilots were trained in methods that were excellent against German and Italian equipment but suicide against the acrobatic Japs”, as Lt.Gen. Claire Lee Chennault had to notice. Although not as fast as the British fighter, the Mitsubishi fighter could out-turn the Spitfire with ease, sustain a climb at a very steep angle, and stay in the air for three times as long.
Allied pilots soon developed tactics to cope with the Zero. Due to its extreme agility, engaging a Zero in a traditional, turning dogfight was likely to be fatal. It was better to swoop down from above in a high-speed pass, fire a quick burst, then climb quickly back up to altitude. (A short burst of fire from heavy machine guns or cannon was often enough to bring down the fragile Zero.) Such “boom-and-zoom” tactics were used successfully in the China Burma India Theater (CBI) by the “Flying Tigers” of the American Volunteer Group (AVG) against similarly maneuverable Japanese Army aircraft such as the Nakajima Ki-27 Nate and Nakajima Ki-43 Oscar. AVG pilots were trained by their commander Claire Chennault to exploit the advantages of their P-40s, which were very sturdy, heavily armed, generally faster in a dive and level flight at low altitude, with a good rate of roll.
Another important maneuver was Lieutenant Commander John S. “Jimmy” Thach’s “Thach Weave”, in which two fighters would fly about 60 m (200 ft) apart. If a Zero latched onto the tail of one of the fighters, the two aircraft would turn toward each other. If the Zero followed his original target through the turn, he would come into a position to be fired on by the target’s wingman. This tactic was first used to good effect during the Battle of Midway and later over the Solomon Islands.
Many highly experienced Japanese aviators were lost in combat, resulting in a progressive decline in quality, which became a significant factor in Allied successes. Unexpected heavy losses of pilots at the Battles of the Coral Sea and Midway dealt the Japanese carrier air force a blow from which it never fully recovered.
Throughout the Battle of Midway Allied pilots expressed a high level of dissatisfaction with the Grumman F4F Wildcat. The Commanding Officer of USS Yorktown noted:-
“The fighter pilots are very disappointed with the performance and length of sustained fire power of the F4F-4 airplanes. The Zero fighters could easily outmaneuver and out-climb the F4F-3, and the consensus of fighter pilot opinion is that the F4F-4 is even more sluggish and slow than the F4F-3. It is also felt that it was a mistake to put 6 guns on the F4F-4 and thus to reduce the rounds per gun. Many of our fighters ran out of ammunition even before the Jap dive bombers arrived over our forces; these were experienced pilots, not novices.”
They were astounded by the Zero’s superiority:-
“In the Coral Sea, they made all their approaches from the rear or high side and did relatively little damage because of our armor. It also is desired to call attention to the fact that there was an absence of the fancy stunting during pull outs or approaches for attacks. In this battle, the Japs dove in, made the attack and then immediately pulled out, taking advantage of their superior climb and maneuverability. In attacking fighters, the Zeros usually attacked from above rear at high speed and recovered by climbing vertically until they lost some speed and then pulled on through to complete a small loop of high wing over which placed them out of reach and in position for another attack. By reversing the turn sharply after each attack the leader may get a shot at the enemy while he is climbing away or head on into a scissor if the Jap turns to meet it.”
In contrast, Allied fighters were designed with ruggedness and pilot protection in mind. The Japanese ace Saburō Sakai described how the toughness of early Grumman aircraft was a factor in preventing the Zero from attaining total domination:
“I had full confidence in my ability to destroy the Grumman and decided to finish off the enemy fighter with only my 7.7 mm machine guns. I turned the 20mm cannon switch to the ‘off’ position, and closed in. For some strange reason, even after I had poured about five or six hundred rounds of ammunition directly into the Grumman, the airplane did not fall, but kept on flying! I thought this very odd—it had never happened before—and closed the distance between the two airplanes until I could almost reach out and touch the Grumman. To my surprise, the Grumman’s rudder and tail were torn to shreds, looking like an old torn piece of rag. With his plane in such condition, no wonder the pilot was unable to continue fighting! A Zero which had taken that many bullets would have been a ball of fire by now.”
When the powerfully armed Lockheed P-38 Lightning, armed with four “light barrel” AN/M2 .50 cal. Browning machine guns and one 20 mm autocannon, and the Grumman F6F Hellcat and Vought F4U Corsair, each with six AN/M2 heavy calibre Browning guns, appeared in the Pacific theater, the A6M, with its low-powered engine and lighter armament, was hard-pressed to remain competitive. In combat with an F6F or F4U, the only positive thing that could be said of the Zero at this stage of the war was that, in the hands of a skillful pilot, it could maneuver as well as most of its opponents. Nonetheless, in competent hands, the Zero could still be deadly.
Due to shortages of high-powered aviation engines and problems with planned successor models, the Zero remained in production until 1945, with over 11,000 of all variants produced
The American military discovered many of the A6M’s unique attributes when they recovered a largely intact specimen of an A6M2, the Akutan Zero, on Akutan Island in the Aleutians. During an air raid over Dutch Harbor on June 4th, 1942, one A6M fighter was hit by ground-based anti-aircraft fire. Losing oil, Flight Petty Officer Tadayoshi Koga attempted an emergency landing on Akutan Island about 20 miles northeast of Dutch Harbor, but his Zero flipped over on soft ground in a sudden crash-landing. Koga died instantly of head injuries (his neck was broken by the tremendous impact), but the relatively-undamaged fighter was found over a month later by an American salvage team and was shipped to Naval Air Station North Island, where testing flights of the repaired A6M revealed both strengths and deficiencies in design and performance.
The experts who evaluated the captured Zero found that the plane weighed about 2,360 kg (5,200 lb) fully loaded, some 1,260 kg (2,780 lb) lighter than the Grumman F4F Wildcat, the standard United States Navy fighter of the time. The A6M’s airframe was “built like a fine watch”; the Zero was constructed with flush rivets, and even the guns were flush with the wings. The instrument panel was a “marvel of simplicity … with no superfluities to distract [the pilot].” What most impressed the experts was that the Zero’s fuselage and wings were constructed in one piece, unlike the American method that built them separately and joined the two parts together. The Japanese method was much slower, but resulted in a very strong structure and improved close maneuverability.
Captain Eric Brown, the Chief Naval Test Pilot of the Royal Navy, recalled being impressed by the Zero during tests of captured aircraft. “I don’t think I have ever flown a fighter that could match the rate of turn of the Zero. The Zero had ruled the roost totally and was the finest fighter in the world until mid-1943.” American test pilots found that the Zero’s controls were “very light” at 320 kilometres per hour (200 mph), but stiffened at faster speeds (above 348 km/h, or 216 mph) to safeguard against wing failure. The Zero could not keep up with Allied aircraft in high-speed maneuvers, and its low “never exceed speed” (VNE) made it vulnerable in a dive. While stable on the ground despite its light weight, the aircraft was designed purely for the attack role, emphasizing long range, maneuverability, and firepower at the expense of protection of its pilot. Most lacked self-sealing tanks and armour plating.
A6M2 Type 0 Model 21 (see model below)
After the delivery of the 65th aircraft, a further change was worked into the production lines, which introduced folding wingtips to allow them to fit on aircraft carriers. The resulting Model 21 would become one of the most produced versions early in the war. A feature was the improved range with 520 l (140 US gal) wing tank and 320 l (85 US gal) drop tank. When the lines switched to updated models, 740 Model 21s had been completed by Mitsubishi, and another 800 by Nakajima. Two other versions of the Model 21 were built in small numbers, the Nakajima-built A6M2-N “Rufe” floatplane (based on the Model 11 with a slightly modified tail), and the A6M2-K two-seat trainer of which a total of 508 were built by Hitachi and the Sasebo Naval Air Arsenal.
Hobbymaster BRAND NEW TOOLING 1/48th scale HA8801 Hobbymaster A6M2b Zero Fighter Type 21 “Pearl Harbor” LCDR Shigeru Itaya, Akagi Fighter Squadron, First Wave Fighter Leader, Dec 1941
Hobbymaster have announced their latest addition to their 1/48th scale Fighter Range. This model is proving very popular even before the price has been announced.
You can still pre-order your model from Flying Tigers by emailing firstname.lastname@example.org or by calling 01604 499034 , Monday to Friday 9.00 a.m. to 5.00 p.m. Answer machine also available over the weekend and out of hours.
Corgi Aviation Archive 1/72nd scale Mitsubishi A6M2 Zero, AI-I54 s/n.5289, Petty Officer 1st Class Takashi Hirano, IJN Aircraft Carrier Akagi, Pearl Harbor attack, 7th December 1941
Hobbymaster New Model Announcements !
Hobbymaster have just announced their latest model releases which can now be ordered from Flying Tigers. Apart from the new 1/48th scale A6M2b Zero Fighter, there are some great new WWII and Modern Jet subjects which are already starting to sell very well. If there is one of the following models in which you are interested , simply click on the link or image below and it will trake you straight to the model page to pre-order, or alternatively you can simply CLICK HERE to see them all..
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