B77W Vs 77W? How To Understand Aircraft Codes When Booking Flights

Commercial planes are given a two, three, or four-character alphanumeric code to designate their aircraft type. Aircraft types that are later modified may also be given a different code. Aircraft codes are defined by both the International Air Transport Association (IATA) and the International Civil Aviation Organization (ICAO). ICAOcodes are published in the ICAO’s ‘Document 8643 Aircraft Type Designators.’