with callsigns used by other operators. The callsign should be easily and phonetically pronounceable in at least English, the international language of aviation. For example, Air France' callsign is "Airfrans"; 'frans' is the phonetic spelling of 'France'. In the previous years, alpha-numeric callsigns have been adopted by airlines (mostly in Europe) to minimise callsign confusion over the radio. These kind of callsigns may include a combination of: a digit and a letter, digit and two letters or two-digits and one letter. e.g. Airfrans 65 Kilo (AFR65K). Accounting number or prefix code The airline accounting code, or prefix code, is a 3-digit number, referenced by IATA and unique among all the airlines, used to identify the airline in various accounting activities such as ticketing. For instance, Lufthansa (LH/DLH) has been assigned 220 as accounting code, and all the flight tickets issued by that airline start with "220-". The IATA code search page references the accounting code for every airline having one. See also International Air Transport Association airport code International Civil Aviation Organization airport code Notes References External links International Civil Aviation Organization Official site ICAO On-line Publications Purchasing Official site IATA's Airline and Airport Code Search Codes Call signs International Air Transport Association Lists of abbreviations