Mitsubishi A6M Zero

The Mitsubishi Navy Type 0 Carrier Fighter also designated as the 'Mitsubishi A6M Rei-sen' and 'Mitsubishi Navy 12-shi Carrier Fighter', was a long range fighter aircraft operated by the Imperial Japanese Navy Air Service from 1940 to 1945. The A6M was usually referred to by the Allies as the "Zero", from the 'Navy Type 0 Carrier Fighter' designation. The official Allied reporting codename was Zeke.

When it was introduced early in World War II, the Zero was the best carrier-based fighter in the world, combining excellent maneuverability and very long range. In early combat operations, the Zero gained a legendary reputation as a "dogfighter", achieving the outstanding kill ratio of 12 to 1, but by 1942 a combination of new tactics and the introduction of better equipment enabled the Allied pilots to engage the Zero on more equal terms. The Imperial Japanese Naval Air Service also frequently used the type as a land-based fighter. By 1943, inherent design weaknesses and the increasing lack of more powerful aircraft engines meant that the Zero became less effective against newer enemy fighters that possessed greater firepower, armor, and speed, and approached the Zero's maneuverability. Although the Mitsubishi A6M was outdated by 1944, it was never totally supplanted by the newer Japanese aircraft types. During the final years of the War in the Pacific, the Zero was used in kamikaze operations. In the course of the war, more Zeros were built than any other Japanese aircraft.




The Mitsubishi A5M fighter was just entering service in early 1937, when the Imperial Japanese Navy started looking for its eventual replacement. In May they issued specification 12-Shi for a new 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.



Mitsubishi's chief designer, Jiro Horikoshi, felt that the requirements could be met, but only if the aircraft could be made as light as possible. Every weight-saving method was used. Most of the aircraft was built of T-7178 aluminum, a top-secret aluminum alloy developed by the Japanese just for this aircraft. It was lighter and stronger than the normal aluminum used at the time, but was more brittle. In addition, no armor was provided for the pilot, engine or other critical points of the aircraft, and the self-sealing fuel tanks that were becoming common at the time were also left off. This made the Zero lighter and more agile than most other aircraft at the start of the war, but also made it prone to catching fire and exploding when struck by enemy rounds.

With its low-wing cantilever monoplane layout, retractable wide-set landing gear and enclosed cockpit, the design was one of the most modern in the world. The Zero had a fairly high-lift, low-speed wing with a very low wing loading; combined with the light weight, this gave it a very low stalling speed of well below 60 kn (110 km/h; 69 mph). This is the reason for the phenomenal turning ability, allowing it to turn more sharply than any Allied fighter of the time. Roll rate is enhanced by servo tabs on the ailerons which deflect opposite to the ailerons and make the control force much lighter. The disadvantage is that they reduce the maximum roll effect at full travel. At 160 mph (260 km/h) the A6M2 had a roll rate of 56° per second. Because of wing flexibility, roll effectiveness dropped to near zero at about 483 km/h (300 mph) indicated airspeed.

The A6M is universally known as the Zero from its Japanese Navy type designation, Type 0 Carrier Fighter 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 their plane Zero-sen. The meaning of the A6M official designation was that "A" signified a carrier-based fighter, "6" for the sixth such model built for the Imperial Navy, and "M" for the manufacturer, Mitsubishi.

The first Zeros (preseries A6M2) went operational in July 1940. On 13 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 for no losses. Before they were redeployed a year later, the Zeros had shot down 99 Chinese aircraft (266 according to other sources).

At the time of Pearl Harbor 420 Zeros were active in the Pacific. The carrier-borne Model 21 was the type encountered by the Americans, often much further from its carrier than expected, with a mission range of over 2,600 km (1,600 mi). Thanks to a combination of excellent maneuverability and firepower, the Zero easily disposed of the motley collection of Allied aircraft sent against it in the Pacific in 1941, while its tremendous range allowed it to appear over distant battlefronts and give Allied commanders the belief there must be several times as many Zeros as there actually were. The Zero quickly gained a fearsome reputation. However, it eventually lost air superiority due to the gradual development of suitable tactics and new aircraft by the Allies. During World War II, the Zero destroyed at least 1,550 American aircraft.

Designed for attack, the Zero gave precedence to long range, maneuverability, and firepower at the expense of protection most had neither self-sealing tanks nor armor plate - and many Zeros and their pilots were too easily lost in combat. During the initial phases of the Pacific conflict, the Japanese trained their aviators far more strenuously than their Allied counterparts. Thus, unexpectedly heavy pilot losses at the Coral Sea and Midway made them difficult to replace.

Nonetheless, until the end of the war, in competent hands the Zero could still be deadly. Due to the scarcity 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.


General characteristics

• Crew: 1
• Length: 9.06 m (29 ft 9 in)
• Wingspan: 12.0 m (39 ft 4 in)
• Height: 3.05 m (10 ft 0 in)
• Wing area: 22.44 m² (241.5 ft²)
• Empty weight: 1,680 kg (3,704 lb)
• Loaded weight: 2,410 kg (5,313 lb)
• Powerplant: 1× Nakajima Sakae 12 radial engine, 709 kW (950 hp)
• Aspect ratio: 6.4

Performance

• Never exceed speed: 660 km/h (356 kn, 410 mph)
• Maximum speed: 533 km/h (287 kn, 331 mph) at 4,550 m (14,930 ft)
• Range: 3,105 km (1,675 nmi, 1,929 mi)
• Service ceiling: 10,000 m (33,000 ft)
• Rate of climb: 15.7 m/s (3,100 ft/min)
• Wing loading: 107.4 kg/m² (22.0 lb/ft²)
• Power/mass: 294 W/kg (0.18 hp/lb)

Armament

• 2× 7.7 mm (0.303 in) Type 97 machine guns in the engine cowling
• 2× 20 mm Type 99 cannons in the wings, with 60 rounds
• 2× 60 kg (132 lb) bombs or
• 1× fixed 250 kg (551 lb) bombs for kamikaze attacks

* Mitsubishi A6M Zero