Originally Posted by
LarryJ
They couldn't. That would put them over max landing weight at destination.
47,000 max landing weight plus, rough guess, 2,900 burn on a direct(ish) routing would be a max takeoff weight of 49,900.
When they add more fuel for the longer routing you end up fueling to something more than 49,900. When the route is shortened later, you're too heavy to go.
I think I'm still missing some piece of the logic, here. Are flights planned to have at or near the maximum landing weight on arrival, then?
When I said that 30 mins is a rounding error, I wasn't referring to the weight added by the fuel. I was referring to the variation in operational flight time. Surely it's normal to look at a flight and say that it is 2.5 hours plus
or minus 20 minutes (whatever the actual numbers are). How can a minus 30 min scenario be so uncommon that it isn't considered in fuel planning? On such a short flight that wouldn't otherwise need a lot of fuel, I can only thing that the plane was fueled to be at maximum landing weight on arrival.