Concorde wasn't quite as inefficient as you might think, used a lot of fuel but flew faster.
According to this article: An Untimely and Unnecessary Demise
then it uses 6 gallons of fuel per mile, compared to 5 gallons of fuel per mile for a 747. So difference in fuel consumption is mainly due to the smaller number of passengers. And (again from that article) the expense of Concorde was more due to other factors including high maintenance costs than the fuel consumption - with the $400 per passenger (when full) for fuel consumption only a tiny part of the total ticket cost of $11,000 per passenger. And final demise was due to other factors such as the Paris crash, and changes in numbers of people using it post 9/11. See also CONCORDE SST : FAQ
So - maybe supersonic flight does have a future if some future airplane fixes those issues (just updated this after researching into Concorde's fuel consumption) .
Apart from that, there are two ways to go faster for long distances in a fuel efficient way that I know about.
One is to fly in space, and there are plans that could let planes fly directly into space from an ordinary runway - and other ways to reduce cost of flight to space - may well have one of those in use by 2050.
One possiblity here is the UK Skylon, a jet that will be able to fly directly to orbit. It would launch from an ordinary runway - like an airplane - the runway needs to be strengthened but is otherwise normal. And it doesn't need booster rockets at all, it carries all its fuel on board.
has a massive reduction of fuel needs because it is air breathing in the early stages of its flight.
This is under active development right now, they are working slowly but steadily towards their goals. So one day it might happen.
This of course is of no use if you just want to travel a relatively short distance, say a thousand miles for instance.
For this and more ideas, see also Projects To Get To Space As Easily As We Cross Oceans - A Million Flights A Year Perhaps - Will We Be Ready?
The other way is to use evacuated tubes - a common theme of science fiction. This is the idea of the Vactrain - which would theoretically be faster than airplanes - and use far less fuel also. And can be scaled down to short distance flight also as in Elon Musk's hyperloop (which would travel at just under the speed fo sound at its fastest).
Vactrain
London To New York In An Hour, By 4,000Mph ‘Vactrain’
At the moment this has many practical issues. Ultra-efficient 4,000 mph vacuum-tube trains - why aren't they being built?
So - maybe one or the other of those two will be in place by 2050, or improved supersonic flight without the same issues as Concorde.
Or - if we had abundant energy - for instance micro-fusion, or abundant solar power - the energy required may no longer be an issue.
According to this article: An Untimely and Unnecessary Demise
then it uses 6 gallons of fuel per mile, compared to 5 gallons of fuel per mile for a 747. So difference in fuel consumption is mainly due to the smaller number of passengers. And (again from that article) the expense of Concorde was more due to other factors including high maintenance costs than the fuel consumption - with the $400 per passenger (when full) for fuel consumption only a tiny part of the total ticket cost of $11,000 per passenger. And final demise was due to other factors such as the Paris crash, and changes in numbers of people using it post 9/11. See also CONCORDE SST : FAQ
So - maybe supersonic flight does have a future if some future airplane fixes those issues (just updated this after researching into Concorde's fuel consumption) .
Apart from that, there are two ways to go faster for long distances in a fuel efficient way that I know about.
One is to fly in space, and there are plans that could let planes fly directly into space from an ordinary runway - and other ways to reduce cost of flight to space - may well have one of those in use by 2050.
One possiblity here is the UK Skylon, a jet that will be able to fly directly to orbit. It would launch from an ordinary runway - like an airplane - the runway needs to be strengthened but is otherwise normal. And it doesn't need booster rockets at all, it carries all its fuel on board.
It burns a mixture of hydrogen and oxygen, but in the early stages it gets the oxygen from the atmosphere. It does that by a remarkable system that cools down the incoming air by 140C in a hundredth of a second, so can take in the air and still use lightweight materials.Artist's concept of it taking off into orbit
has a massive reduction of fuel needs because it is air breathing in the early stages of its flight.
This is under active development right now, they are working slowly but steadily towards their goals. So one day it might happen.
This of course is of no use if you just want to travel a relatively short distance, say a thousand miles for instance.
For this and more ideas, see also Projects To Get To Space As Easily As We Cross Oceans - A Million Flights A Year Perhaps - Will We Be Ready?
The other way is to use evacuated tubes - a common theme of science fiction. This is the idea of the Vactrain - which would theoretically be faster than airplanes - and use far less fuel also. And can be scaled down to short distance flight also as in Elon Musk's hyperloop (which would travel at just under the speed fo sound at its fastest).
Vactrain
At the moment this has many practical issues. Ultra-efficient 4,000 mph vacuum-tube trains - why aren't they being built?
So - maybe one or the other of those two will be in place by 2050, or improved supersonic flight without the same issues as Concorde.
Or - if we had abundant energy - for instance micro-fusion, or abundant solar power - the energy required may no longer be an issue.
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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