|Quoting CitationJet (Reply 1):|
They wouldn't hold the second flight just to avoid duplicate call signs. Most likely they would change the call sign of the second flight slightly (like adding an extra digit on the front). The would only be for ATC, as far as the passengers are concerned, there would be no difference, except for the thru passenger from ORD to SYD who has now missed his "connection".
|Quoting IAHFLYR (Reply 2):|
Some airlines add the above mentioned extra digit while others will tag a letter to the end of the flight number, ie., AAL122W, again simply for ATC purposes, t
|Quoting Don81603 (Thread starter):|
Can both flight 863's be in the air at the same time, or would they hold the SFO-SYD leg until the ORD-SFO landed?
|Quoting RoseFlyer (Reply 4):|
I believe that United uses the call signs 81XX for duplicate flights that could potentially be in the same airspace at the same time. I