I was wondering what’s the policy of refueling commercial jet liners once they land. Do they always depart with a full load of fuel regardless of the destination?
No, airliners take off with a load of fuel that will get them to their destination, plus a reserve. Carrying unused gas just adds weight and decreases “gas mileage”, decreasing profits.
So unless they need it, there’s no reason to necessarily take off with a full fuel load.
Sorry, no cite, this is based upon working peripheral to the field.
No. Carrying extra weight means burning slightly more fuel, so often airliners have just enough fuel to get to the destination, plus a reserve amount in case they are diverted.
Another factor is reducing turnaround times - the planes will often leave one airport with enough fuel to go several legs without refueling. So, the plane might make two stops without getting more fuel.
It is up to the pilot to make sure that he’s comfortable with how much gas the plane has, and get more if needed.
I’m pretty sure that on some of the short flights I’ve been on with EasyJet (London-Amsterdam), the plane was turned around without refuelling; it’s only about an hour’s flight and they herd the new passengers on the plane as soon as the last of the old crowd is through the gate.
Yes, it all depends on the economics of the specific route system the plane is scheduled to fly that day. It takes fuel to carry all that fuel, and it isn’t always worth it.
But private pilots have a saying that the only time you have too much fuel on board is when you’re on fire.
Also, I think military planes that are on alert are kept fueled. You never know when you will have to go, and a tanker might not be around, or you can’t get to it because you have other concerns at the time.
But commercial airliners? No. Careful account is made of fuel on board to insure that there is enough for the flight, including needed reserves. But in spite of the careful record keeping, airliners on at least two occasions that I know of, have run out of fuel.
A comment about the private pilots and fuel –
There are times when I fly with less than full fuel, and this has to do primarially with weight issues. The Cessna 150 I fly can only lift so much weight off the ground. If I have a particularly heavy passenger I may exceed that limit and, since passenger frown on me lopping off thier limbs to meet weight limits, something else has to give. About the only thing I can leave on the ground is “excess” fuel.
So, for example, if I have a 250 lb passenger (not likely!) in the Cessna I will only fill the gas tanks half full so the airplane will be able to get over the trees and powerlines in the area. I am then obligated to plan my flight(s) accordingly, stopping more frequently to buy fuel so as to not run out of it before the wheels touch the ground. Strictly a safety issue here.
Any other time, though, I like to fill up. I did take one trip where, due to costs, I did not fully fuel but only bought enough to get me home with a safe reserve but that was most certainly an exception to the rule.
There is no regulation dictating how often you need to refuel at any level of civil aviation, only the rule that you must have enough fuel on board to reach the next intended point of landing plus a reserve of either 30 (for daytime private pilots) or 45 minutes (everybody else). Whether you load up all at once for an around-the-world trip like Rutan’s Voyager or you stop multiple times between the beginning and end of your trip is entirely up to you.
Commercial airlines would, of course, try to work out the most economical method of doing this - which may include a mix of fueling at stops and fueling enough to make several stops without buying more go-juice. Company policies would vary from airline to airline in the details.