Mitsubishi Type 0 Carrier Fighter Reisen / A6M Zero, Hamp, Zeke
Technical Information

Background
Designed by Mitsubishi chief designer Jiro Horikoshi during 1937 to replace the A5M4 Claude. Officially designated the Type 0 Carrier Fighter by the Imperial Japanese Navy (IJN). Known as simply Reisen the Japanese word for the number Zero.

The Zero was well armed, lightweight fighter that could not be out-turned, and exceptional range. When the outside world learned about the new fighter aircraft, it was a surprise as previously Japanese aircraft designs were deemed to be inferior. Arguably, the Zero became the most famous and successful Japanese Navy aircraft of World War II.

Wartime History
The first Zeros entered combat on September 13, 1940 in China during the Second Sino-Japanese War. At the start of the Pacific War, the Zero helped the Japanese Navy fly long range escort missions and fighter sweeps over distant targets and was superior to every Allied fighter aircraft in the first years of the Pacific War.

Allied Code Names
To the Allies, popularly known as the "Zero". a term was often applied to any Japanese single engine fighter. The official Allied code names were "Zeke" for the A6M2 Model 21 and later A6M5 Model 52. "Hamp" for the A6M3 Model 22 or A6M3 Model 32 with square wingtips. "Rufe" for the Type 2 Float plane Fighter / A6M2-N.

By 1943, the arrival of new Allied fighter aircraft revealed deficiencies in the Zero including the lightweight construction that could sustain little damage and the lack of self-sealing fuel tanks. Despite these flaws, the Zero continued to be upgraded with a more powerful engine and increased armament and remained in use until the official surrender of Japan in September 1945.

A6M2 Model 21 Zero (Code Name: Zeke)
Built by Mitsubishi and Nakajima.

The Zeros built by Nakajima had a "dummy" numbers in their codes to deceive production totals. The first number and the second number from the right are "dummy" number that equal 10. Example: 6541 (6+4=10). By the end of September 1942, Nakajima had produced 303 A6M2 Model 21 Zeros.

During September 1943, 20mm cannon 100 round magazines came into use in A6M2 Zeros.

A6M3 Zero "Hamp"
When it was first observed by the Allies, the A6M3 was thought to be another airplane type, due to its square wingtips and assigned the code name "Hamp". When understood to be another model of Zero the name was dropped. All A6M3 Model 22 and Model 32 were built by Mitsubishi starting in June 1942. The manufacture numbers were derived by adding a "3" in front of the m/n. So the 274th A6M3 would have the coded 3274. By the end of October 1942, Mitsubishi built a total of 250. Production for the month of November 1942 was 67. Mitsubishi was producing Model 32s at the rate of 2.2 per day. 274-250=24. 24/2.2 = 10.9 days.

The Model 22 Zero had folding wingtips and adjustable trim tab on the aileron.

Type 2 Float Plane Fighter / A6M2-N Rufe
Other variants, such as the A6M2-N Rufe float plane version of the fighter existed, a modified A6M2 with a centerline float and smaller wing floats.

Field Modified Two Seat Version
A two-seater version did exist, with the second crew member serving as an observer / wireless operator.  This was a two seat field modification conceived by commander Tomoyoshi Hori. A rear facing seat for an observer was installed behind the pilot with a telegraph for transmitting long range communications during reconnaissance missions. At least two A6M2 Model 21 Zeros were field modified including A6M2 Zero 31870 and A6M2 pilot Kawato.

A6M5 Model 52 Zero
The first A6M5 flew in August of 1943. In spite of an increase in all-up weight of 440 pounds, the A6M5 was faster than the A6M3 Model 32, and could reach a maximum level speed of 351 mph at 19,685 feet. It had a more powerful engine and armament package. The general opinion is that the first manufacture number was A6M5 Zero 3904.

A6M5c Hei
Added more armor plate on the cockpit windshield and behind the pilot's seat. The wing skinning was further thickened in localized areas to allow for a further increase in dive speed. This version also had a modified armament fit of three 13.2 mm machine guns, one in the forward fuselage, and one in each wing with a rate of fire of 800 rpm plus twin 20 mm Type 99 Mark II cannons. The Zero could carry an additional fuel tank with a capacity of 367 L (97 US gal) or a single 250 kg bomb.

A6M6 Zero
Only one example was assembled.

A6M7 Model 62 Zero
Last production model of the Zero that entered production in May 1945. The A6M7 Model 62 was a a fighter-bomber that could also operate from smaller aircraft carriers. The centerline bomb rack could carry a 250 kg bomb or 500 kg bomb and was also used for kamikaze missions. For dive bombing, the A6M7 had a reinforced vertical stabilizer, and a centerline bomb rack for a 250 kg or 500 kg bomb and could mount 2 x 350 litre drop tanks and on the underside of the wings.

A6M7 Model 63 Zero
The A6M7 model 63 was equipped with Nakajima Sakae 31-B aircraft engine without methanol water injection and had a two stage supercharger.

A6M8 Model 64
The A6M8 was similar to the A6M6 but with the Sakae engine replaced by the Mitsubishi Kinsei 62 engine delivering 1,163 kW (1,560 hp) and required extensive cowling and nose modifications to fit this engine. The carburetor intake was larger with a long duct and spinner. The armament was two 13.2 mm Type 3 machine guns and two 20 mm Type 99 cannons in the wings. The Model 64 was modified to carry two 150 L ( drop tanks on either wing and could mount a single 250 kg bomb on at the centerline. During April 1945, two prototypes were completed and flown but the model did not enter production before the end of the Pacific War.

Production
A total of 10,964 were built by Mitsubishi and Nakajima including all models.

Technical Details
Crew  One (pilot)
Engine  1 x Sakae 14-cylinder air-cooled radial driving three bladed propeller
Span  12.1m
Length  9.15m
Height  3.05m
Maximum Speed  332 mph at 14,930' / 534 kmh at 4,550m
Range  1,930 miles
Armament  (upper nose cowling) 2 x Type 89 7.7mm machine guns (wings) 2 x Type 99 20mm cannon with 60/100 round magazine
Underwing  (centerline) 320 liter drop tank (wing hard points) 2 x 60 kg aerial bombs