The famous Mitsubishi A6M, popularly
known as the 'Zero', was the first carrierborne
fighter in the world capable
of outperforming any contemporary
land-based fighter it was likely to confront.
Because of inept Allied intelligence
it was able to achieve immediate
air superiority over the East Indies
and South East Asia from the day Japan
entered the war. Designed under the
leadership of Jiro Honkoshi in 1937 as a
replacement for the neat but obsolescent
A5M, the prototype A6M1 was
first flown on 1 April 1939 with a 582kW Mitsubishi Zuisei 13 radial;
production A6M2 fighters with
two wing-mounted 20mm guns and
two nose-mounted 7.7mm guns were fitted with the 708kW Nakajima Sakae 12 radial, and
it was with this version that the
Japanese navy escorted the raiding
force sent against Pearl Harbor, and
gained air superiority over Malaya, the
Philippines and Burma. In the spring of
1942 the A6M3 with two-stage supercharged
Sakae 21 entered service, later
aircraft having their folding wing
tips removed. The Battle of Midway
represented the Zero's combat zenith;
thereafter the agile Japanese fighter
found itself ever more outclassed by
the American F6F Hellcat and P-38
Lightning. To counter the new American
fighters the A6M5 was rushed to
front-line units; this version, with Sakae
21 engine and improved exhaust system,
possessed a top speed of 565km/h, more A6M5s (and subvariants)
being produced than any
other Japanese aircraft. It was five
A6M5s of the Shikishima kamikaze unit
that sank the carrier St Lo and damaged
three others on 25 October 1944.
Other versions were the A6M6 with
water-methanol boosted Sakae 31 engine
and the A6M7 fighter/dive-bomber.
Total production of all A6Ms
was 10,937. (The reporting name'Zeke'
was given to the A6M, and 'Rufe' to a
float version, the A6M2-N.)
| ENGINE||1 x Nakajima NK1F "Sakae 12", 705kW|
| Take-off weight||2410-2796 kg||5313 - 6164 lb|
| Empty weight||1680 kg||3704 lb|
| Wingspan||12.0 m||39 ft 4 in|
| Length||9.06 m||30 ft 9 in|
| Height||3.05 m||10 ft 0 in|
| Wing area||22.44 m2||241.54 sq ft|
| Max. speed||525 km/h||326 mph|
| Cruise speed||330 km/h||205 mph|
| Ceiling||10000 m||32800 ft|
| Range w/max.fuel||3050 km||1895 miles|
| Range w/max.payload||1850 km||1150 miles|
| ARMAMENT||2 x 20mm cannons, 2 x 7.7mm machine-guns, 60kg of bombs|
|A three-view drawing (752 x 1009)|
450 rpm was the RoF for the cowl Type 3 13.2mm HMG.
The IJNAF Zero fighter proved to be the master of early Allied fighters it met on it's debut in China.
The A6M2 was only successfully dealt with by the Flying Tigers with hit and run diving tactics. But most did not heed them when they warned the US about the Zero even before Pearl Harbor was attacked. For the next 6 months it took on all comers even virtually annihilating a Spitfire Wing in Burma!
The A6M2 Zero was the first strategic escort fighter with unbelievable range. Flights could last all day.
It was able to do a full 360 turn in about 11 seconds, but roll rate was bad with speed: 56 dgs/sec @ 160 mph and 37 @ 324 mph. Stick forces were so heavy over 240 mph.
Most all early Allied fighters had worse altitude performance than the Zero.
Zero pilots could reportedly get 345 mph with boost.
It could climb 4517 fpm, but dive limit was less than 410 mph.
It had 2 light MGs and 2x 20mm cannons (just like the Bf 109E). Ammo: 60 rpg for the 20mm and MV was low. RoF was slow too @ 520-550 rpm.
It's acceleration was excellent, giving Allied pilots the impression it was faster than their planes even if their top speed was higher.
Just like early war fighters in 1939 Europe, it had no armor. The Zero's defense was offence.
Just as important, it had many veteran pilots.
The A6M3 had 2 versions. First the clipped wing Model 32 which had improved dive limit of 416 mph and better altitude performance, roll rate and acceleration. But a full turn took over 12 seconds and climb was 3100-4500 fpm, still good enough but range was much shorter causing many losses.
So the more numerous Model 22 restored the full span and added fuel tankage to become the longest range Zero. Some had the new high velocity 20mm cannons, but RoF was slower @ 490 rpm. Most now had 100 rpg ammo.
By now the Zero had lost it's mystique as well as too many experienced pilots at Midway. Besides that, a second generation of powerful US fighters were overmatching the A6M in combat with the tactics like the Flying Tigers used. They avoided fighting the Zero's fight. Zero pilots had to be good deflection shots to score with only a 6 shell cannon burst against the well armored American fighters. especially feared was the Corsair, Lightning (up high), and British Spitfire Mk VIII.
The zenith of the Zero had been reached. Now it was on the defence and still no armor when all other Japanese fighters had at least some pilot protection by this stage.
Now came the most numerous A6M5 Model 52. The design team intended it to get a 1500+ hp engine upgrade but this was turned down by the Navy Brass! This combined with abbreviated pilot training, doomed not just the Zero but Japan.
It did about 350+ mph with the short span of the clipped Model 32. The Model 52 took over 16 seconds to complete a full 360 turn (the A6M5a,b,c and especially the A6M7 would take more time than the lighter A6M5). It also got 125 rpg for the cannons. With the A6M5b came bullet proof glass in front and some fire protection.
By the end of the war the last 240 Zeros (A6M5c & A6M7) finally got armored pilot seatbacks (but only about half the 16mm thickness in the Ki 61-II pilot armor) out of over 10,000 produced! This degraded their top speed to 340-345 mph but these could dive 460 mph. They now had at least 5 guns too. 13.2mm MGs were added, fist to the cowl (replacing one 7.7mm gun) with 230 rpg, later to the wings with 240 rpg. RoF was 800 rpm; 400 rpm synchronized in the cowl. Now overweight, it was obsolete, a shadow of past glory. Even the late model P-40N was a now a threat (at least down low)!
The IJNAF torch had long since been passed to the N1K Shiden fighter-bomber and J2M Raiden interceptor.
Rate of roll for the A6M2:
Best was at speeds much less than 160 mph, but at that speed it rolled 56 dgr/sec.
It really started to stiffen controls with speed:
52 dgr/sec @ 230 mph;
50 dgr/sec @ 250 mph;
37 dgr/sec @ 324 mph (NACA chart limit for Model 21 Zero).
Zero pilots likely preferred to stay far from 324 mph rolls, or even 250 mph. Who knows how good it rolled off the slow end of the NACA chart? None of the other fighters did their best rate under 160 mph so that's where the comparison chart starts unfortunately.
Of about 6,000 A6M5s, 470 were A6M5bfrom mid 1944;
93 were A6M5c from Sept, 1944.
These were produced after Jiro Horikoshi was replaced and, failing to get the intended Kinsei 62, were out-performed by even the Ki 43-IIIa in speed as well as max range, climb, acceleration and aerobatics. However the Zero had improved it's firepower and was catching up in protection.
Since Allied fighters were less agile, they tended to take straight shots especially the USAAF.
If the Japanese planes all added a cannon in the tail-cone, it could have played havoc with would-be assailants. Low percentage deflection shots would be resorted to even more by the Allied pilots.
Perhaps the obsolete Zero and Oscar would have had more of a fighting chance after the first year of glory. Even when diving away after attacking B-29s, a 30mm cannon stinger could give a telling parting shot from Japanese interceptors (perhaps a 37mm cannon on twin engine Japanese fighters). Any US escort fighter would be distracted if not intimidated.
As it was, the slow Zero and Oscar soldiered on beyond their prime and Japanese pilots liked it that way, unfortunately for them.
Perhaps this simple addition of a high velocity tail-stinger on ALL their fighters would have gone a long way to even the odds when Japan was thrown onto the defensive.
A6M3/5 pilots who didn't want to lose their speed would do fast yoyos and limit turns to 45 dgs. Over Okinawa some used fast barrel rolls and violent skids in the Zero. Energy tactics capilaizing on initial acceleration, but not as extended as the Allied pilots.
Anthony Cooper's 'Darwin Spitfires' site posts the RAAF Spitfire Vc Trop comparison with the Zero 32.
There it has the 1G stall speed of 55 knots per hour IAS or 63 mph for the Hamp and a max level speed of 291 knots or 335 mph @ 16,000' and a ceiling of 32,500'.
Though the Mk VcT had a speed and ceiling advantage, the Hamp was competitive due to it's lighter wing and power loading even around the Spit's critical altitude of 21,000' (5,000' higher than it's own). It's acceleration compensated up to 30,000' for speed limit disadvantage. A loop would cause the Spit to stall at the top if it followed. Even a dive initially favored the A6M3 due to acceleration not to mention the carb problem requiring the Mk VcT to half-roll first to dive. The Zero could do a negative-g dive no sweat.
The new engine of the Hamp gave it better altitude prowess than the old A6M2.
Perhaps the sluggish Mk VcT was the weak link in the chain of Spitfire contenders vs the zenith of the Zero Hamp before fading into obsolesence when the A6M5 was denied an engine upgrade.
Many are unaware of the fact that Zeros and Spitfires met in combat for 5 months of raids on Darwin, Australia.
I posted the mock dogfight evaluation by the RAAF between a captured A6M3 Hamp and a Spitfire Mk V Trop at the Spitfire site.
The pilots on both sides of the battle included many aces so they weren't below average, second string greenhorns as suggested by some after trying to rationalize the results.
The tactics had been already adjusted following the previous annihilation of a virtual Wing of Spitfires in Burma against Japanese pilots (Oscars mostly).
So the Spitfire pilots were overconfident, not expecting even a stand-off or draw this time.
Problem is the new cipped wing Zero 32 showed up!
It owned the Spitfire below 20,000'. But it avoided combat over 30,000'. Niether side could win.
Too many Spitfires were lost but they held the sky.
Thing is the lowly P-40E did better at Darwin than the Spitfire did against the Zero!
The Curtis lacked the climb rate and high altitude performance but had reliable guns that didn't freeze and malfunction up there either; it also had better acceleration than the Mk V tropicalized Spit, not to mention better dive and roll.
With enough warning both RAAF fighters could dive on the Japanese bombers with firing passes and escape the Zeros.
The following is from an AIAA report, dated 1976.
It was not until late 1942 that a captured Zero was made available to the U,S, Technical Intelligence Unit for flight test. Excerpts from the USATI are as follows.
The zero fighter is superior to all our present service type aircraft in regards to maneuverability. It is necessary to maintain a speed of over 3oo mph indicated tp successfully combat this aircraft. This superiority is recognizable in the fact that maximum manifold pressure can be maintained from sea level to 16,000 feet.
1 DO NOT ATTEMPT TO DOGFIGHT THE ZERO.
2 Never maneuver with the zero at speeds less than 300mph indicated
Never follow the Zero in a climb at low speeds. Service type ships will stall at the steep angle where the Zero has reached its most maneuverable point. At this point it is possible for the Zero to complete a loop and attack from the rear.
The RoF for the synchronized 13.2mm cowl HMG, starting with A6M5b Zeros, was perhaps 400 rpm. It's been said that it is faster than the heavier US Browning gun but that may be true only of the P-39 cowl 0.50 (12.7mm) HMG (reduction gear drive), not prop drive designs like the P-40C ets... After all, the 13.2mm Type 3 is even larger caliber than the MG131's 13.1mm and the round is heavier. Therefore, the way faster 700 rpm synchronized rate found at some forums are suspect in my opinion since it is still a Browning based design like the Army Airforce Ho-103 at 900 rpm and 400-450 rpm synchronized.
400 rpm is a 50% reduction from the uninterrupted 800 rpm wing mounted Type 3s of the A6M5c and A6M7. That seems in line. I've seen 400 rpm online as well as 700 so I'll lean toward the 400 as more credible.
Speaking of the underpowered A6M5c and 7, I can't see weighing down the wings with a pair of Type 3s but leaving only 1 Type 3 in the cowl instead of a pair. The 0.30mm has no place by this late date against US aircraft!
If the only ace the Zero can play by then is manuverability, don't add this weight to the wings until more power is under the hood, if then.
What's your opinion?
The A6M3 Model 32 with clipped wings lessened control stiffness at speed.
It was the full span A6M3 Model 22 that got the high velocity cannons. It also restored the range lost by the Hamp.
Make that, (Some old myths never die).
Some old myths never lie, such as the old WWII chest-nut that the Mitsubishi A6M was a copy of the Howard Hughes R1 racer. The only things these two aircraft have in common are they both are single seat single radial engine monoplanes with a wide tract landing gear. The wing profile, fuselage, and control services are all different. The R1 was made with aluminum alloy and the A6M used large amounts of Magnesium in its airframe. This material and the lack of self-sealing fuel tanks and little or no pilot armor protection gave the A6M a very low wing loading, making it very maneuverable and giving it an excellent range. Once the US pilots learned not to get into a turning match with the A6M, the Zeke’s vulnerability became apparent.
Is there a evidence to prove that zero fighter was even sent from Japan to Germany during WW2?
The disappointing A6M6 failed to reach production status.
The A6M7 production run of 148 Zeros coincided with the Mk5 of the Model 2 Type 99 production from May 1945. This could br significant. Hold that thought.
This fighter-bomber not only had full protection but also bomb and rocket rails that slowed it down and still without the needed engine power of the faster A6M8.
If they were finally armed with that new faster Mk5 cannon, they now had a 5kg salvo per second of high velocity fire!
These 20 mm cannons had a rate of 750 rpm each and the 13.2 mm HMGs, also wing-mounted had a rate of 800 rpm each and the one in the cowl was 700 rpm synchronized. How many fighters can match that? 9.9g of HE in some of it's 20 mm shells and over 63 rps pattern of density with the heaviest standard MG in WW2. The J2M or N1K had 48 rps pattern density.
Many A6M7s were used as night fighters in 1945, not just as bomb toting kamikazes.
Even If it was now surpassed in speed by the latest Ki 43-IIIa (still just 2 MGs), the A6M7 certainly improved its bite at least (that's smart. Its slow top speed could be less of a handicap than as a day fighter).
The cannon armed Ki 43-IIIb was only pre-production to my knowledge.
The A6M2 could out-gun, outloop and out-run the Ki 43 but not out-roll or out-turn it.
The A6M3 had the new high velocity 20 mm cannon (Type 99 Model II)
The A6M7 fighter-bomber had a level top speed of 340 mph (no water-methenol injection). 150 produced. Used for Kamikazi mostly.
Hughes statement to that effect before congress was an obvious attempt to enhance his stature with hubris evoking a stereotype that had traction back then.
However it was more factual that the Fw 190 was inspired in part by his 1935 racer, not the Zero! This was so dispite the fact that the Focke-Wulf tail looked different.
It's true that the Hughes racer had the pointy tail-end as did the A6M Reisen (like its predecessor the Mitsubishi A5M), but so did other fighters of WW2 like the Macchi and Fiat designs. But the propaganda wouldn't 'fly' if those were mentioned instead of the vaunted Japanese fighter. No one would believe the Italian or German planes were 'copies'.
Jiro Horikoshi didn't sit still for this slander by Hughes either. It's a matter of record.
This is a good site for exploding such false myths about Japanese fighter designs or anyone elses.
The vail of WW2 propaganda should be lifted by now. It had its day already.
Any truth to the old rumor that Mitsubishi was influenced by the Howard hughes racer built in 1935 in the design of this airplane? Epinage design is very similar.
'The wind rises' movie is highly recommended. This tribute to the love of flight shared among plane designers isn't aimed only at aviation buffs.
The pre-war back-story of Mitsubishi fighters is the main focus of the A6M designer's saga rather than WW2 and its aftermath which are very brief but present in the film. Horikoshi's romantic love interest is compelling for all audiences, to round out the movie.
Till the end the Zero made up at least half of the Japanese fighters encountered.
Since it was effectively obsolete for the last half of the Pacific war, I wonder what it would have been like if they had teamed up with other more competent types like the Shiden for a given mission -- like the Allies did with Ausie P-40s down low, F4U mid-level, and P-38s higher up.
Maybe they did and I haven't heard of it.
As a 'what if' scenario at least, since the A6M5 had the numbers and the N1K had the competence, combined - both types would be better off as one fighter force together. Maybe even some Raidens could serve as top cover on short flights. Leaving out army fighters for now since inter- service rivalry was so strong.
Maybe 1 unit of J2Ms, 2 units of NiKs, and 7 units of Zeros.
Not such a walk-over as all A6M5s alone!
Same for the army side. Perhaps the Oscar's numbers could be spearheaded with late war types likewise. Again, maybe they were. I think Ki 43s and Tonys complimented eachother on flights.
Can you imagine trying to dive from a Zero - only to find a Jack pouncing on you?
Do you have any comments about this aircraft ?