In flight refuelling for commercial airliners

Large planes like C-5 can be refulled and the technology is a mature one.

I understand the costs involved, but I would have thought that the advantages would be sufficient to overcome that issue.

  1. Increase the range of existing aircraft, your A320 and B757 and B747 suddenly are long range aircraft.

  2. Increase carrying capacity.

I can’t imagine a market model that would encourage it. Furthermore, don’t people like to get out of the plane and stretch their legs every 12 hours or so?

In any case, it depends on the cost/benefit picture, and my guess is, if it made economic sense, they’d be doing it.

In addition, what is the safety margin? I understand doing this for military purposes. Is it safe enough for commercial traffic?

Alan Cobham’s company, Flight Refuelling Limited, repeatedly tried to promote this in the 1940s, but no commercial airline was interested. As the efficiency and range of commercial aircraft has greatly increased since even the 1970s, there seems to be less of a case for it than ever.

I think that a plane uses much more fuel taking off than flying at altitude. To send a heavily laden tanker up after it makes no economic sense - if it needs mid flight refueling, it can land somewhere for a lot less cost.

Military planes have a different problem in that many countries around the world are not too keen on other people’s military aircraft overflying their borders. Especially if they are carrying nuclear warheads.

A few thoughts - the full cost of the Air Force delivering one gallon of gas inflight is about $42 for $4 worth of gas. That includes aircrew, operations, and so on. Now, I would bet you that a commercial company would be cheaper than that, but how would an airline justify such great costs? There are already scheduled flights of 17 hours or so, why would additional range be needed?

Plus, let’s remember that planes are configured for their specific use. No first class passenger is going to pay a lot of money to fly 12 hours on a 737-class seat. No way.

Er… those already ARE long-range aircraft. They’re routinely flown across the world’s widest oceans. How much more range do you really need?

This is a good point. I know that I get the same amount of seating space if I fly a 737 compared to a 747 or 777. But there is a huge psychological difference between flying a wide body with twin aisles and a single aisle narrow body. I’ve flown 14-15 hour flights in 747s and 777s; I can’t imagine how cramped it would feel to do that in a 737.

How many legs are out of range of a B747?
I’ve flown non-stop from Hong Kong to NYC - how many passengers need to travel farther than that every day?

If in-flight refueling allowed airlines to carry more paying passengers, it might conceivably justify its inevitably high cost. But the aircraft you cite - and indeed all modern airliners - routinely take off with every seat full and enough fuel to make long flights.

So there’s no apparent way to generate much additional revenue with this scheme, and thus probably little interest in it.

It is certainly possible because Air Force One, a 747, has this capability. I’ve heard that it is a dangerous operation, but if they let the President do it, the danger is probably limited.

Air Force One has a different “mission” than a commercial airliner. A commercial airliner exists to get you from point A to point B. Air Force One is a transportation vehicle, but it also functions as a mobile White House and seat of government and during the Cold War it was given in-flight refueling capability so it could remain a moving target instead of being forced to land for more gas. That justifies the expense, and if we’re at war it’s arguably less risky to refuel in flight than to remain at a fixed location.

There are a few conceivable routes that are out of range of all commercial airliners even today. I think NYC to Sydney would be an example. However, there are not very many that have a lot of demand, certainly not enough to justify the expense of a in-flight refueling system.

Currently, the longest non-stop scheduled flight is between Sydney, Australia and DFW, Texas – a distance of 13,804km (8,578mi.) This is somewhat shorter than the previous record-holder, Newark to Singapore (15,345km/9,535mi) which is just shy of half the distance 'round the world at the equator. IOW, there’s no two points on earth which are beyond the range of modern passenger jets; the only factor is economics.

Mid-air refueling is expensive and dangerous. Which is why it’s used exclusively for military flights, where carrying lots of fuel and/or stopping routinely to fill up the tank is a significant liability. I suppose the President’s plane could refuel in mid-flight during a national crisis, though.

You probably get more space on any aircraft doing an international route, usually about an inch of width and maybe an extra inch of legroom.

Plus, of course, many international aircraft have better entertainment systems.

That assumes that all airline pilots are as skilled as the pilot who flies Air Force One and the one that flies the tanker plane.

I can’t imagine that many passengers would pay for a ticket for a flight that left the ground without enough fuel to reach the destination.

I know several Navy pilot who’ve done inflight refueling - they don’t feel it requires any uncommon skill.

But it does require special equipment aboard the plane receiving fuel, which would add weight and cost. In the absence of any significant advantage, it ain’t gonna happen.

Very minor point, but that’s not quite true.

There is no commercial aircraft which can do Sydney to London (great circle distance 10,573 miles, 17,016 km) nonstop with anything like a viable passenger load. A Qantas 747-400 did London to Sydney once to get the record, but there was almost no-one on board - going the other way against the jetstream wouldn’t work. For reference, the 747-400ER has a stated range of 14,205 km and the Airbus A380 has a stated range of 15,700 km.

Certainly there are very few routes which cannot be flown non-stop (and none which require more than one stop), and no economic justification for in flight refuelling in those few cases.

I’d love to be able to fly Australian East Coast to London (a trip I do every year or two) non-stop. I don’t know exactly how long the stopover adds to the journey but it would be no less than about four hours and hellava lot of hassle.

There would be a market for the non-stop trip, it just that it’s not a market that is going to bear the cost, I would guess.

Wow, that would suck. I had to to Tokyo to Dulles and that was awful. I’d rather loose a few hours at an airport so I can walk a little. Then again, I’m in coach.