Question: What was the name of the Japanese carrier-borne fighter that was typically the capital ship of the fleet?
Context: A flotilla (from Spanish, meaning a small "flota" (fleet) of ships, and this from French "flotte"), or naval flotilla, is a formation of small warships that may be part of a larger fleet.  A flotilla is usually composed of a homogeneous group of the same class of warship, such as frigates, destroyers, torpedo boats, submarines, gunboats, or minesweepers.  Groups of larger warships are usually called squadrons, but similar units of non-capital ships may be called squadrons in some instances, and flotillas in others.  Formations including more than one capital ships, e.g. men-of-war, battleships, and aircraft carriers, typically alongside smaller ships and support craft, are typically called fleets, each portion led by a capital ship being a squadron or task force (see reference below). The first "South Dakota" class was a class of six American battleships that were laid down in 1920 but never completed.  They would have been the last dreadnoughts in the Naval Act of 1916 to be commissioned had the Washington Naval Treaty not caused their cancellation one-third of the way through their construction.  They would have been the largest, most heavily armed and armored battleships in the U.S. Navy and, designed to achieve 23 kn , represented an attempt to abandon its 21 kn standardized fleet speed and catch up with the increasing fleet speeds of its main rivals, the British Royal Navy and Imperial Japanese Navy.  In this, size and secondary armament, they represented a break from the Standard-type battleship that had dominated American capital ship design for the prior five ship classes, while their use of standardized bridges, lattice masts and other features was a continuation of this practice and the increase in the number of main guns from the preceding "Colorado" class had long been standard U.S. naval policy.  The main restriction to which they had to adhere was the ability to pass through the Panama Canal. The capital ships of a navy are its most important warships; they are generally the larger ships when compared to other warships in their respective fleet.  A capital ship is generally a leading or a primary ship in a naval fleet. The Heinkel HD 23 was a carrier-borne fighter biplane designed in Germany at Heinkel Flugzeugwerke in the 1920s, for export to Japan.  Two examples were delivered to Aichi as pattern aircraft in 1927.  Aichi added rudimentary flotation capability and built two further examples as the Type H Carrier Fighter, but full-scale production was not started. The Nakajima A2N or Navy Type 90 Carrier-based fighter was a Japanese carrier-borne fighter of the 1930s.  It was a single-engined biplane of mixed construction, with a fixed tailwheel undercarriage. An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and facilities for carrying, arming, deploying, and recovering aircraft.  Typically, it is the capital ship of a fleet, as it allows a naval force to project air power worldwide without depending on local bases for staging aircraft operations.  Aircraft carriers are expensive to build and are critical assets.  Carriers have evolved since their inception in the early twentieth century from wooden vessels used to deploy balloons to nuclear-powered warships that carry numerous fighter planes, strike aircraft, helicopters, and other types of aircraft.  While it is possible to launch heavier aircraft such as fixed-wing gunships and bombers (it has been done) from aircraft carriers, it is virtually impossible to land them. The Fairey Fulmar was a British carrier-borne fighter aircraft that served with the Fleet Air Arm (FAA) during the Second World War.  A total of 600 were built by Fairey Aviation at its Stockport factory between January 1940 and December 1942.  The Fulmar's design was based on that of the earlier Fairey P.4/34 that was in turn developed in 1936 as a replacement for the Fairey Battle light bomber.  Although its performance (like that of its Battle antecedent) was lacking, the Fulmar was a reliable, sturdy aircraft with long range and an effective armament of eight machine guns. The Fairey Flycatcher was a British single-seat biplane carrier-borne fighter aircraft made by Fairey Aviation Company which served in the period of 1923 to 1934.  It was produced with a conventional undercarriage for carrier use, although this could be interchanged with floats for catapult use aboard capital ships. HMS "Resistance" was the second of two "Defence"-class ironclad s built for the Royal Navy in the 1860s.  She was the first capital ship in the Royal Navy to be fitted with a ram and was given the nickname of "Old Rammo".  "Resistance" was initially assigned to the Channel Fleet upon commissioning, but was transferred to the Mediterranean Fleet in 1864, the first ironclad to be assigned to that fleet.  She was rearmed in 1867 and became a guardship when recommissioned in 1869.  The ship was reassigned to the Channel Fleet in 1873 before reverting to her former duties in 1877.  "Resistance" was decommissioned in 1880 and was used for gunnery and torpedo trials beginning in 1885.  The ship was sold for scrap in 1898 and foundered in 1899 en route to the breaker's yard.  She was salvaged and later scrapped. The Fairey Firefly was a British Second World War-era carrier-borne fighter aircraft and anti-submarine aircraft of the Fleet Air Arm (FAA).  Designed to the contemporary FAA concept of a two-seat fleet reconnaissance/fighter, the pilot and navigator/weapons officer were housed in separate stations.  It was superior in performance and firepower to its predecessor, the Fulmar, but entered operational service only towards the end of the war when it was no longer competitive as a fighter.  The limitations of a single engine in a heavy airframe reduced its performance, but it proved to be sturdy, long-ranged, and docile in carrier operations.
Answer: Nakajima A2N