Explaining Aircraft Identifications Question

[p38p51]

Hello. Can someone tell me why an aircraft sometimes has two designators--for example I am watching an aircraft identified on FR24 as BA93 and BAW9L. It seems I often
see two idents on various aircraft. I assume it's a simple explanation and hope someone can help. Thanks./Bill

[p38p51]

Thanks Amper, appreciate your input. I worked ICAO aircraft communications for 35 years so am familiar with ICAO terminology. My followup question would be when and where would the 2 different idents be used, ie in my example that aircraft could
be called Speedbird 93 or Speedbird 9 Lima. It would seem confusing for the same aircraft to have two idents unless in one area, ie Europe one may be used and another area the other? Hope you can clear it up a bit more. Thanks./Cheers/Bill

[Amper]

sorry,deleted post before your answer. misunderstood your question.

[p38p51]

No problem--another example we have an aircaft on line which is listed as BA219 and BAW19V---it seems confusing to have the same aircraft identified two different ways, so I'm wondering where each ident would be used? Cheers/Bill

[p38p51]

ishot-3908.jpg This aircraft just passed through Canadian Airspace and presently in U.S. Airspace.

[t-kclt2]

In your example, BAW19V is used for ATC purposes only. See http://www.eurocontrol.int/services/...ty-css-service for some additional details. Its aim is to reduce confusion when similar callsigns are used (and on frequency). BA219 is still the flight number that passengers would refer to (for example).

And sometimes even pilots get confused about it.. for fun listen to "Speedbird 174": https://www.youtube.com/watch?v=ZMQJUIWQt6c

[p38p51]

t-kclt2 Thanks for the heads up on it all. I think the amount of various acronyms in the first link is almost as confusing as the call sign scenario! The BA174 was a good one. Cheers/Bill Canada.