Originally Posted by
goldstj2
UA uses a similar convention on ORD-BOS (520s through 540s) and ORD-LGA (668 through 694), to name two.
However, I know ORD-BOS isn't as consistent as DCA (there's an 881/882 thrown into the ORD-BOS schedule), and of course ORD-LGA has the much-loved Shuttle America flights interspersed throughout the day.
The 881/882 sequence BOS/ORD is a tag to the ORD/NRT flights.
Weren't UA1/2 the round-the-world flights in opposite directions when UA served India? There were a couple of changes-of-gauge as I recall but you could fly RTW on a single flight number.