Aircraft callsigns

[Morris542]

I've been casually wandering what determines a commercial aircraft callsign. Many flights use their flight number, eg: EZY 8552. However many aircraft have a callsign different to their flight number with letters thrown in. Eg: EZY 8AB (flight number EZY 5478). What determines the aircraft callsign and why is it frequently a mixture of letters and numbers?

[HEATHROW DIRECTOR]

Callsigns are often designed to prevent confusion with each other. For example Aer Lingus 148 and Speedbird 148 arriving together might cause confusion. Therefore some callsigns are changed to, for example, alpha-numeric so that the two mentioned above might become Aer Lingus 14XM and Speedbird 14TN.

HTH

[ANDYSPPR]

Morris 542

being the anorak I am I like to keep a list of these alpha-numeric flights. I currently have a list 2200 flights long. The EZY flights are relatively easy because, as you mention, they ofetn have part of the flight number in them. RYR, TCX and TOM are a little more complicated and bare little relation to the flight number. WZZ however often really confuse me. They used to be relatively simple but have recently become more complicated. I think a flight has a callsign assigned according to the base of the aircraft used and the day of the week.

If anyone else knows how they work them out please let me know.

Andy S

[HEATHROW DIRECTOR]

The callsign, in whichever format, refers to the route to be flown at a particular time. Flight plans for regular flights are stored on ATC computer systems so they do not refer to a particular aircraft. Airlines sometimes change the type at short notice but the callsign will remain the same. For example BA 1234 will always be the Shuttle service from A to B but for callsign purposes it will use "Shuttle 1 X-ray irrespective of the aircraft type used (not genuine numbers but merely to demonstrate).

[vulcanised]

What is really disappointing is when Intergalactic Zero Two turns out to be a C150.

[Skipness One Echo]

I currently have a list 2200 flights long

Some operators like Lufthansa and BA CityFlyer change the callsigns season by season whereas some stay the same for years, (BA and EZY). Ryanair have also gone alphanumeric of late, many callsigns are now random and have no apparent logic.

Logic threw up the issue of having BMA1, BMA51, BMA411, BMA331 and BMA81 all stacking at Bovingdon in the first wave of arrivals. Way too many similarities and ones !

[Hotel Tango]

I heard from a friend that Wizzair change their callsigns every month!