How is it that the estimated duration of a SYD-SCL flight (7060 miles) on a 747-400 (cruise speed Mach 0.85) is 12:40, but SCL-AKL flight (6011 miles) on a 787-8 (same cruise speed) takes 13:20.

My first thought was perhaps wind direction. So I ran a quick calculation assuming SYD-SCL always has a 10m/s tail wind, and SCL-AKL has a 10m/s head wind. The numbers come out as:

7060 miles / (252.1m/s + 10m/s) = 12:02
6011 miles / (252.1m/s - 10m/s) = 11:06

So it's probably not wind, so why does it take longer for a 1000 mile shorter flight?

  • Argh, super powers in air-travel. I think it's a dupe in that the answer is the same - the drag of the spin of the earth, instead of flying with the drag, you're flying against it. If you don't think it's a dupe, feel free to vote to reopen.
    – Mark Mayo
    Jun 16, 2015 at 3:16
  • 1
    Ah so my issue is grossly under approximating the wind speed.
    – James
    Jun 16, 2015 at 3:40
  • And when you say "drag of spin", you mean the prevailing wind yes?
    – James
    Jun 16, 2015 at 3:42
  • Basically, yes. The air is dragged with the earth, My answer here has a quote describing it better than I can :)
    – Mark Mayo
    Jun 16, 2015 at 3:49


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