Airline codes-O

A list of all Airline codes. The table lists the IATA airline designators, the ICAO airline designators and the airline call signs (telephony designator). Historical assignments are also included for completeness.

IATA airline designator

IATA airline designators, sometimes called IATA reservation codes, are two-character codes assigned by the International Air Transport Association (IATA) to the world's airlines in accordance with the provisions of IATA Resolution 762. They form the first two characters of the flight number.

Designators are used to identify an airline for all commercial purposes, including reservations, timetables, tickets, tariffs, air waybills, and in airline interline telecommunications. There are three types of designator: unique, alpha/numeric, and controlled duplicate.

IATA maintains two policies to deal with the limited number of available codes:

1. after an airline is delisted, the code becomes available for reuse after six months;
2. IATA issues "controlled duplicates".

Controlled duplicates are issued to regional airlines whose destinations are not likely to overlap, in such a way that the same code would be shared by two different airlines. The controlled duplicate is denoted here with an asterisk (*) following the code and in IATA literature as well.

ICAO airline designator

The ICAO airline designator is a code assigned by the International Civil Aviation Organization to aircraft operating agencies, aeronautical authorities, and services. The codes are unique by airline which is not true for the IATA airline designator codes.

Each aircraft operating agency, aeronautical authority, and services related to international aviation is allocated both a three-letter designator and a telephony designator. The designators are listed in ICAO Document 8585: Designators for Aircraft Operating Agencies, Aeronautical Authorities and Services. The ICAO codes originally based on a two-letter-system and were identical to the airline codes used by IATA. After an airline joined IATA its existing ICAO-two-letter-code was taken over as IATA code. So in the 1970s the abbreviation BA was the ICAO code and the IATA code of British Airways while non-IATA-airlines like Court Line used their 2-letter-abbreviation as ICAO code only. In the early 1980s ICAO introduced the current three-letter-system due to the increasing number of airlines. It became the official new standard system in November 1987.

An example is:

• Operator: American Airlines
• Three-letter-ICAO-designator: AAL (the original ICAO-two-letter-designator AA was used until 1987 and is also the IATA code of the airline)

Certain combinations of letters are not allocated to avoid confusion with other systems (for example SOS). Other designators (particularly those starting with Y and Z) are reserved for government organizations.

Designator YYY is used for operators that do not have a code allocated.

Call signs

Most airlines employ a distinctive and internationally recognized call sign that is normally spoken during airband radio transmissions as a prefix to the flight number. The flight number is normally then published in their public timetable and appears on the arrivals and departure screens in the airport terminals served by that particular flight. In cases of emergency, the airline name and flight number, rather than the individual aircraft's registration, are normally mentioned by the main news media.

Some call signs are less obviously associated with a particular airline than others. This might be for historic reasons, or possibly to avoid confusion with a call sign used by an established airline.

Not all of these operators of aircraft are civilian and some only operate ad hoc chartered flights rather than scheduled flights; some operate both types of flights. Some cargo airlines specialize in freight transport, an emphasis that may be reflected in the company's name.

Companies' assigned names may change over time as a result of mergers, acquisitions, or change in company name or status. Country names can also change over time and new call signs may be agreed in substitution for traditional ones. The country shown alongside an airline's call sign is that wherein most of its aircraft are believed to be registered, which may not always be the same as the country in which the firm is officially incorporated or registered. There are many other airlines in business whose radio call signs are more obviously derived from the trading name.

The callsign should normally resemble the operators name or function and not be confused with callsigns used by other operators. The callsign should be easily and phonetically pronounceable in at least English, French, Spanish or Russian.

Codes

^{* on IATA code indicates a controlled duplicate. italics indicates a defunct airline.}

See also

• IATA airport code
• ICAO airport code

Notes

External links

• International Civil Aviation Organization (official site)
• ICAO On-line Publications Purchasing (official site)
• Airline Designator / Code Database Search (from The Airline Codes Web Site)
• Airline Designator / Code Database Search (from Aviation Codes Central Web Site - Regular Updates)
• Airline Designator/Code Listing (from FAA Web Site)