-Mitsubishi A5M (Claude)
Koko recieved a few units for evaluation in 1937, then started production locally in 1938 for what would become its first carrier-based fighter aircraft. By the time production wrapped up in January 1942 a total of 493 A5Ms had been built by four different Kokoan aircraft manufacturers (Enomoto, Ikehara, Okajima and Tokuda). Operationally the fighter was effectively embarked only on the two light carriers Ahodori and Fukuro and by the sart of the war in December 1941 all had been replaced by the A6M on frontline duties. The A5M then served in limited fashion on the escort carriers and land-based units until late 1943. 88 machines were converted into trainers by adding a second cockpit for the instructor pilot and operated in this new role until the end of the war.
-Mitsubishi A6M Reisen (Zeke/Zero)
With local production starting in 1940, the renowned Rei-Sen fighter entered service with Koko no Kaigun in March 1941, and by the time conflict erupted in the Pacific some 130 were in service. The A6M2b model formed the mainstay of Koko's frontline carrier-fighters for the first year of the war before progressively being moved to the escort carriers, land-based and second-line units. When production ended in early 1943, 796 machines had been built.
The A6M3 featured a more powerful engine and reduced wingspan with squared wingtips among other modifications, which increased top speed at the expense of range. It debuted in July 1942 just after the Battle off Midway, replacing the A6M2 as Koko's main carrier-based fighter until the introduction of the A7T a year later. Kokoan factories assembled 726 airframes before production ended in early 1944. Many surviving planes of this two earlier model planes were later upgraded with the addition of armor fo the pilot and increased armament (two 13mm machine guns replacing the fuselage mounted 7.7mm pieces) that, while impacting speed and on a lesser extent maneuverability and range, gave them slighly more durability and firepower to face US aircrafts, although a fight against a Corsair was usually hopeless anyway.
Despite born outdated, the A6M5 model was nevertheless produced in large numbers by Kokoan factories, both in its -a and -b models, featuring upgraded armament compared to the baseline. Never seeing frontline service and being only sporadically embarked on escort carriers the A6M5 joined A6M2s and 3s on land-based units and acted as a sort of backup fighter when and if needed. 1.617 were built between 1943 and 1946. Later into the conflict many were given extra armor for pilot protection and three 13mm machine guns in place of the whimpy 7.7mm pieces, giving them the similar offensive capabilities of an A6Mc.
In Addition to the fighter models, Koko also manufactured the two-seat A6M2-K to augment and replace the A5M4-K as the Navy's advanced trainer. 372 were assembled beginning in 1943, with production lasting until the end of the war.
Overall, Koko built a total of 3.139 Reisens between 1940 and 1946
-Tokuda A7T Kazan (Harp)
Design for a domestic carrier-borne fighter started in late 1940, roughly at the same time the IJN had asked Mitsubishi for a successor for the A6M. Tokuda, the most experienced Kokoan aircraft manufacturer, was given the task by Koko no Kaigun naval staff, who wanted an home-grown design as well just in case delays happened. This proved to be a wise move as developement of the A7M kept stalling until mid 1942. Engine choice befell on the new Nakajima Homare, which promised as much as 1.900 hp of power. The result was a low-wing monoplane that slightly resembled a longer, larger, more streamlined A6M (the cokpit design was mostly unchanged) with folding wings that promised a 650km/h top speed. The A7T, also given the designation name Kazan (Volcano), first flew in august 1942, and featured a still respectable (for the time) armament of two 20mm wing-mounted cannons and two fuselage-mounted 7.7 machine guns. Soon during trials the Homare11 engine proved to have output and reliability problems that effectively limited it to 1.650hp, which led to a reduction in top speed to around 600 km/h at best. Despite the aircraft did not exhibit the same top-level maneuverability of an A6M it was still an extremely agile fighter and was some 60km/h faster than the most recent Reisen models, all while also featuring self-sealing fuel tanks and more extensive pilot protection. The A7T1a was thus approved into production and finally made its carrier debut in june 1943. Its frontline service was short hower, as the improved A7T2 reached service less than 4 months later. The aircraft still found its use in land based units after that. A total of 738 were built between mid 1942 and early 1944.
A new model based on the baseline airframe was developed by Kokoan maufacturer Ikehara specifically for escort carriers operations and named A7T1b. It featured numerous small modifications which included the removal of the drop tank attach points in lieu of a rack capable of fitting up to a single 250kg bomb. This reduced range by over 400km, but such drawback was deemed acceptable given the second-line duties the aircraft was expected to serve, and the lighter aircraft was actually 10km/h faster than an -a model. 1.032 were maufactured in Koko between late 1943 and early 1946. Further 820 airframes were asembled in Japan under license.
While underpowered compared to what was initially promised, the baseline model of the Kazan fighter was perfectly suited suited to act as an advanced high-performance training aircraft. Fitted with a second cokpit for the instructor pilot, the resulting A7T1-K was produced in 277 units between 1944 and 1946.
As soon as the first issues with the Homare11 emerged a new model of the A7T was quickly developed by fitting the more powerful and refined Homare12 which, while still short of the promised output, manged to provide 1.825hp of power. This was enough to raise the top speed close to 630km/h, and the aircraft now outperformed the A6M in anything but rate of climb at low altitudes and turning ratio at low speed. Armament was also increased: the fuselage-mounted 7.7mm machine guns were removed and replaced by two 13mm wing-mounted pieces fitted outboard of the existing 20mm cannons. This had also the advantage of increasing forward visibility for the pilot. The A7T2 entered service in late September 1943 and immediately became the primary carrier-based fighter for Koko no Kaigun, distinguishing itself as a realiable, extremely capable and well respected warplane for the rest of the war, a decent match for an F6F hellcat even when in late 1944/1945 it started to suffer significant attrition against the growing US air-power might. A total of 6.611 A7T2s were produced in Koko from late 1942 to early 1946, with another 1.864 license-built in Japan from 1943-on.
A new Kazan model flew in September 1944 and boosted the new Homare 21 engine capable of 2.000hp that finally raised the top speed to 645km/h, close to the originally envisioned numbers. The A7T3 saw a further increase in firepower, being armed with four wing-mounted 20mm cannons. Entering service in January 1945 it was the primary fighter on all light carriers and some of the larger fleet carriers, where it shared service with the A7M. Under the right circumstances, it was a troublesome opponent even for a Corsair. 2.770 were built domestically in only 19 months of production. Japan also manufatured another 835 under license.
Last developement of the family, the A7T4 model flew in August 1945. It was developed from the A7T2 to serve as a fighter/bomber on escort carriers. A strengthened airframe and tail allowed to carry up to a 500kg bomb, and two drop tanks fitted below the wings increased range to almost 2.100km. A dorsal fin-strake and modified wingtips increased stability, all for a slight drop in top speed to 610km/h. Koko built some 282 A7T4s late into the war.
Overall, Koko built a total of 11.710 Kazans between 1942 and 1946, A further 3.519 were assembled and operated by Japan.
-Mitsubishi A7M Reppu (Sam)
Long delayed successor of the Zero, it first entered service with Koko no Kaigun in early 1945. Boosting a similar top speed but increased maneuverability and armament compared to an A7T2, it started replacing the latter on the larger fleet carriers thorough the year. 1.324 units were maufactured under license in Koko during the last two years of the war.
Developement of a naval version of the A7M3 was delegated to Tokuda in order to allow Mitsubishi designers some respite and happened pretty much in parallel. Fitting the newly developed Ha-44-11 engine under the hood, capable of 2.400hp, the A7M3c first flew in September 1945 and Boosted an impressive top speed of nearly 690km/h. Its high speed, maneuverability, durability and heavy armament of six 20mm wing-mounted cannons promised it to be quite a formidable fighter. Despite being immediately approved into production the plane never saw carrier-based service given Koko's deteriorating wartime conditions that culminated with the national uprisings in november of the same year. 184 were manufactured domestically but less of a third of them ever saw active service despite proving themselves quite well in combat. Japan attempted to start production in early 1946, but only 2 airframes were completed before US bombings destroyed tooling and blueprints.