Originally Posted by
SQ421
As others have mentioned, Tailwinds can often help make up delays or arrive early (not the best option when the destination airport has a curfew!)
Flying overnight SIN-SYD, the tailwinds over the interior parts of Australia must have been especially good, as at one stage we looked like making to Sydney about an hour and a bit before the scheduled arrival (taking the routing which more or less cuts diagonally across NT/SA, over north western NSW and into SYD. Post which, the aircraft took a southerly routing, skirting the northern part of Victoria , and over Canberra, into SYD only about 10 or 15 minutes before its scheduled arrival.
So, its not always the fight crew trying to trick passengers. At times, favourable tailwinds can add considerably to the groundspeed and the routing might even be adjusted to not arrive at the destination ridiculously early (my guess is, gate/parking bay availability, landing/parking charges come into picture at this point!)
On most aircraft fuel weight is a concern also, so if they are making TOO good a time they will have to divert to burn fuel. It impacts landing weight and if they are over maxium landing weight, or anticipate being over weight, they will have to fly around to consume it. They cannot dump it unless it's an emergency, so if they were planning that extra hour, the often HAVE to take it even if they made awsome time.