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?