LiveATC Discussion Forums
Air Traffic Monitoring => Listener Forum => Topic started by: dshore on December 05, 2009, 07:28:52 PM
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Listening to Toronto ATC around 7:00 pm tonight I heard the following call sign...
"speedbird five alpha charlie" cleared to Messina. What is the five alpha charlie all about, or did I hear something else ?
Thanks
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BAW5CA
British Airways "Speedbird" (United Kingdom) 5 Charlie Alpha
http://flightaware.com/live/flight/BAW5CA
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Thanks - but why is it not assigned a regular flight number like Speedbird 125 ? Why the letters ?
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If you were to purchase a ticket, the flight is called BA 92
http://www.flightstats.com/go/FlightStatus/flightStatusByFlight.do?id=177668713&utm_source=airlineInformationAndStatus&utm_medium=cpc&utm_campaign=co-op
Why the discrepancy? I don't know.
There's another thread of discussion here
http://www.airliners.net/aviation-forums/general_aviation/read.main/2594302/
which hints that it may have something to do with conflicting callsigns, more precisely, the conflict may occur at Heathrow between similar callsigns addressing ATC at the same time - something conflicting with BA (or Speedbird) 92.
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"SPEEDBIRD" is British Airways callsign.
BA5 is the callsing for BAs' Heathrow (EGLL) to Tokyo Narita (RJAA) route using a B747-400.
BA5CA is the callsign for BAs' Toronto (CYYZ) to Heathrow (EGLL) route using a B767-300.
I also think it's due to conflicting callsings. The "CA" probably is in reference to Canada.
http://www.flightstats.com/go/FlightStatus/flightStatusByFlight.do?id=177744414&utm_source=airlineInformationAndStatus&utm_medium=cpc&utm_campaign=co-op
BA5CA:
http://flightaware.com/live/flight/BAW5CA
BA5:
http://flightaware.com/live/flight/BAW5
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It is to do with conflicting callsigns. Not sure if for BA92 its the depature/enroute or arrival areas but I do know that KLM692 leaves YYZ for AMS within 15 minuts of BA92 and they likely take similar routings over to Europe.
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I asked the exact same question here a few years back. As far as I know it is for conflicting callsigns.
It's particularly common in the UK where most if not all airlines do it.
A few examples are
Shuttle 8A (BA Connect)
Easy 40GF (Easyjet)
Mibland 8EH (BMI)
And the list goes on and on and on.
It's common for BA and their Shuttle and Flyer divisions, Easyjet, Flybe, BMI, Lufthansa and many many others. I've even heard a few US airlines do it when listening to Kennedy.
Have a listen to this clip to hear many more.
http://www.liveatc.net/forums/atcaviation-audio-clips/some-more-egph/
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Some more info .....
4. Numeric v. alphanumeric call signs
4.1. Many airlines continue to use their IATA commercial flight numbers as call sign suffixes. However, because
they tend to be allocated in batches of sequential and very similar numbers, call sign confusion occurs.
4.2. Several airlines have switched to alphanumeric call signs reasonably successfully in recent years. However,
if every operator adopts alphanumeric call signs, the limited choices available within the maximum of 4 elements
allowed within a call sign suffix means that call sign confusion, similar to the existing numeric system,
is likely to result.
4.3. Before changing to an effective all-alphanumeric call sign system, which involves a significant amount of
work, it is recommended that operators review their existing numeric call sign system to deconflict any similar
numeric call signs. Where there is no solution to those call signs that have a potential for numeric confusion,
alphanumeric call signs can be adopted.
http://www.eurocontrol.int/safety/gallery/content/public/library/AGC_action_plan.pdf
So far the only North American airline I've noticed that uses alphanumeric callsigns on a regular basis is SkyWest.
http://flightaware.com/live/flight/SKW82C/history/20091208/1212Z/KPHL/KMKE
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So far the only North American airline I've noticed that uses alphanumeric callsigns on a regular basis is SkyWest.
http://flightaware.com/live/flight/SKW82C/history/20091208/1212Z/KPHL/KMKE
UAL and AWE use them quite a bit as well.
BL.