Originally Posted by
BBadanov
You are on the right track, two syllables for jets, but BEAR is single syllable, therefore prop.
Also these are often incorrectly referred to (even by Wiki, who would have thought?) as NATO names.
Althought they are used by NATO, the names come from the ATIE tech group, then approved by the ASCC standards body.
In the late 1990s this process was given the flick as the designators of Russian and Chinese aircraft were well known, and therefore no need for codenames.
Accordingly, the J-10 received no name, nor have others since.
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I've seen Firebird quoted for the J-10 and Felon for the Su-57.