As an aircraft has the possibility to use radio communication as a transmitting station on the air, it must have a unique designation named call sign.
This call sign must be normally used during air band radio transmissions.
A call sign shall be one of the following types:
The aircraft operating company or agency type is the most widely used within commercial aviation. The flight identification is usually the flight number or flight identification.
On initial contact, a pilot must spell his complete call sign, usually at the end of his message. Always pronounce each digit separately.
After good communication has been established, the abbreviated call sign may be used when initiated by ATC
After satisfactory communication has been established, and provided that no confusion is likely to occur, aircraft call signs may be abbreviated as follows:
A pilot shall use his abbreviated call sign only after the air traffic controller has taken the initiative.
Air traffic controllers can use abbreviated call signs only after satisfactory communication has been established and no confusion with other aircraft on your frequency is possible.
Any aircraft in the heavy wake turbulence category shall include the word "HEAVY" immediately after the aircraft call sign in the initial contact between such aircraft and ATS units. The word "SUPER" shall be used for an Airbus 380 aircraft.
Aircraft call signs may be abbreviated with the first and at least the last two characters of the aircraft registration.
| OOFWA | OSCAR _ _ WHISKEY ALFA |
| N202PY | NOVEMBER _ _ _ PAPA YANKEE NOVEMBER _ _ TWO PAPA YANKEE |
Either the name of the aircraft manufacturer or the aircraft model may be used instead of the first character.
| OOFWA | Robin _ _ _ WHISKEY ALPHA Robin _ _ FOXTROT WHISKEY ALPHA |
| OOTMG | Piper _ _ _ MIKE GOLF Piper _ _ TANGO MIKE GOLF |
The telephony designator of the aircraft operating agency or company call sign followed by at least the last two characters of the registration.
| Speedbird (BAW2595) Registered as GBOAC |
SPEEDBIRD _ _ _ ALPHA CHARLIE SPEEDBIRD _ _ OSCAR ALPHA CHARLIE |
Air traffic controllers must pay attention to call sign confusion when two or more flights with similar flight numbers fly close to each other.
Example: KLM685 and KLM689 / BAW556 and BAW665 / AFR 324 and AFR 342
Air traffic controllers must pay attention that they do not use duplicate abbreviated call signs when 2 or more aircraft share the same. In that case, you must use the complete call sign.
Example: DEHLB and DAHLB share the same abbreviated call sign D_LB
When there is any risk of confusion, the full call sign shall be used all the time.
All aircraft have a unique registration call sign based on the home country.
The aircraft registration call sign is a group of characters and it is constructed with:
- a prefix : the nationality or common mark
- a suffix : registration mark
Spell the call sign on frequency using the NATO Alphabet only.
| Callsign | Prefix | Callsign spelling | Country |
|---|---|---|---|
| OOTWA | OO | OSCAR OSCAR TANGO WISKEY ALFA | Belgium |
| DEDJF | D | DELTA ECHO DELTA JULIETT FOXTROT | Germany |
| FCYAB | F | FOXTROT CHARLIE YANKEE ALFA BRAVO | France |
| N04252 | N | NOVEMBER ZERO FOUR TWO FIVE TWO | USA |
The ICAO airline designator is a code assigned by the International Civil Aviation Organization (ICAO) to aircraft operating agencies, aeronautical authorities, and services related to international aviation.
ICAO formatted call signs start with the 3 letter ICAO code of the airline (prefix) followed by a telephony designator. Each aircraft have a unique call sign with ICAO designator.
| Callsign | ICAO Code | Prefix spelling | Full callsign spelling |
|---|---|---|---|
| VIP 418 | VIP | Freewings | Freewings FOUR ONE EIGHT |
| SVA 011 | SVA | Saudi | Saudi ZERO ONE ONE |
| BCS 666 | BCS | Eurotrans | Eurotrans SIX SIX SIX |
| DLH 1EE | DLH | Lufthansa | Lufthansa ONE ECHO ECHO |
| BAW 4212 | BAW | Speedbird | Speedbird FOUR TWO ONE TWO |
Be careful that the prefix spelling can be very different from the real company name. Example: BAW = Speedbird (prefix spelling) = British Airways (company)
IATA airline designators are two-character codes assigned by the International Air Transport Association (IATA) to the world's airlines.
Airline designator codes follow the 2 alphanumeric characters (letters or digits). It can be followed by an optional letter.
These IATA airline designators are used in real aviation for company flight tickets and at check-in desks.
Examples: SN2268 TV884 KL1722 AF301
In real life IATA abbreviations are NOT used by ATC, pilots and in flight plans. Only ICAO call signs are used.
Do not mix IATA designator and reduced ICAO prefix from 3 characters to 2 characters. In real aviation, some airlines use reduced ICAO prefix for their flights.