TermExplanationExamples
Ya, Yak Initials of Yakovlev design Bureau Ya-7, Yak-36
YaMG Initials of Yakov Modestovich Gakkel YaMG
Ye Alternative spelling for cyrillic E, used for some experimental/prototype aircraft Ye-1, Ye-2 etc
Yer Initials of Yermolaev Design Bureau Yer-2, Yer-4