Warbird Information Exchange

Technical Sergeant Francis Williams suggested that using people's nicknames would make it easy for service personnel to relate an aircraft type to a profile. Fighters and floatplanes were given male names, and bombers, reconnaissance aircraft and flying boats were assigned female names. At a later stage transport aircraft were named with a "T" name, training aircraft were named after trees and gliders were named after birds.

The Japanese aircraft naming system was apparently know as the MacArthur Southwest Pacific Code Name System.

Frank McCoy said that "Sally" was named after his Group Commander's wife , "Claude" was named after an Australian friend, and "Joyce" was named after a WAAAF who worked in his section. Many were named by Technical Sergeant Francis Williams. Williams name "Betty" after a well-endowed nurse that he knew.

During the war just about all combat reports were Japanese "Zeros" even if they were other models. Remember combat and distances were involved. Same as all bombers at some point were "Betty" bombers... The first Ki-61's were reported as Me-109's... we;; that's what they looked like and there was no promo material provided by the Kawasaki for the Allies!

It can be fun reading some of the "after action" reports by Allied pilots. As you mention, most Japanese fighters were called "Zeroes," regardless of actual type or service branch.