Aer Lingus From Ireland, joined May 2000, 1560 posts, RR: 0
Reply 1, posted (14 years 2 weeks 1 day 8 hours ago) and read 890 times:
All I know is that callsigns such as "XXX 128F" (Foxtrot) identify a cargo flight
"XXX 128C" (Charlie) can sometimes mean an extra flight and Brittania uses the Alpha and Bravo endings to signify the outbound and inbound flight respectively
Wjcandee From United States of America, joined Jun 2000, 5150 posts, RR: 22
Reply 2, posted (14 years 2 weeks 1 day 6 hours ago) and read 868 times:
Sometimes when the airlines run an extra section, or when two different planes handle a flight bearing the same number through a hub, an "Alpha" is appended to the latter flight for ATC purposes. For example, if one flight is an hour late coming into a hub and the operations department decides to have it terminate there while they send its continuation out on time using a substitute aircraft (which would then originate with the same flight number while the inbound is still in the air), the newer flight may bear the same flight number with an A at the end, or some digits may be added to the beginning, just to keep them separate and eliminate the possibility of confusion.