The nature of flight numbers confuses me. How do operators decide on flight numbers for a given route? I ask, because here at Tubthumper Tower a resident operator has two flights planned out at the same time, whose flight numbers differ by only one digit. Needless to say, the potential for c
ck-up is huge, and although I haven't fallen foul of it personally (yet), one only has to read the incident digests to see what can, and does, happen as a result of callsign confusion.
So, enlighten me. Is it just random, or is there method to the madness?