Originally Posted by
PRWeezer
Correct. Operationally they will simply call one of them a different # (or 512A, as noted) to avoid confusion. This is an internal designation for the airline/feds, the flight # won't (or rather, shouldn't) change from a passenger's perspective.
I'd never seen this before until now. DL 181 diverted to ANC yesterday. It is leaving this morning as DL 181A. Todays DL 181 is just leaving DTW. So 2 DL 181's will be in the air at the same time.