Japanese Aircraft Designations

The Japanese Navy used two main and two subsidiary aircraft designation systems during the Second World War, causing so much confusion on the Allied side that a fifth codename system was developed.
The Japanese Army Air Force used three overlapping aircraft designation systems – the Type number, based on the year the aircraft was accepted, the Kitai, or airframe number, allocated while a project was under development, and a series of popular names adopted just after the start of the Pacific War.