Originally Posted by
Jumbodriver
Because 3hrs45 is absolutely unachievable! Even on the shortest route LGW-PFO is 1725 miles, allowing 30 mins for taxi out and in that requires an average speed of 530kts. That would need a good 70 knot tailwind for any shorthaul aircraft to achieve schedule. Including a standard routing and speeding up/slowing down youd need an average cruise groundpeed well over 600kts.
The speed difference between a 767 and a 319 would be no more than 5-10 mins max.
Last nights airborne time was 4hrs7 mins out and 4hrs36 back. Thomas Cook are making the schedule up to fit their LGW slots/crew hours I suspect.
If there are good tailwinds between LGW and FCO (though I am not too optimistic about ground times), the 1,982 statute miles (your distance of 1,725 is nautical miles) is just beyond doable. NW schedules its comparable SEA-DTW flights of 1,927 miles for a block time of around 4:06-4:17 (depending on time of day) and generally stays within those times.