FlightAware is German? :) "fife"

If you hold your cursor over a flight’s call sign it’ll show it in the phonetic alphabet. I happen to stumble on this one.
http://i11.photobucket.com/albums/a182/ES44DC/FAmessup.jpg

‘Fife’ is the correct phoenetic pronounciation of ‘5’ per the ICAO/FAA radiotelephony phonetic alphabet.

So is “tree”, although FlightAware doesn’t show it like that.
and most people know “niner”
en.wikipedia.org/wiki/NATO_phonetic_alphabet

Good catch, I’ll get those fixed.

Whoa! “Tree” sounds like “three.”

That’s kinda the point, “tree” stands for three.