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It is the 21st century. We should all be going to work by rocket belt, have a flying car in the garage for family outings, and be able to go halfway around the world on a hypersonic airliner in two or three hours.
One hundred years on from the first commercial airline flight, which was a short hop in Florida with just one paying customer, it is easy to feel the pace of development in aviation has slowed. That 23-minute journey came just a decade after the Wright brothers’ pioneering flight in a powered, heavier-than-air machine.
Much of the progress that followed ran ahead of the infrastructure – flying boats could operate without runways so were used to link continents in the 1930s by the likes of Pan American World Airways and Imperial Airways. But the airfields that mushroomed in the 1940s meant land planes led another era of rapid expansion as jet engines fuelled the growth of commercial aviation.
Since then, however, with the exception of the supersonic and now extinct Concorde, airliner cruise speed has been stuck at about Mach 0.85, while airport infrastructure is once again a brake on growth. Many existing airports lack capacity, while noise and environmental concerns are pushing planned airports further away from the cities that are passengers’ final destinations.
Technological change is still happening, though. Turbofan engines have become, on average, 1 per cent more efficient every year for the past two decades. The Pratt & Whitney geared turbofan, or PurePower engine, that has been chosen for the Bombardier CSeries airliner promises to be 10-15 per cent more efficient than current aero engines.
Yet the pace still needs to step up. The aviation industry has set itself a target of a 50 per cent reduction in carbon emissions by 2050 compared with the levels of 2005. And while packing more passengers on to each aircraft can yield greater efficiency, we have probably already seen in the Airbus A380 superjumbo a limit to the size of aircraft that existing airports can handle,
Encouragingly, aircraft powered by electric motors are rapidly moving from being pie in the sky to a real possibility. Airbus Group Innovations is putting into production two- and then four-seat electric light planes, based on the E-Fan prototype that it will have on display at the Farnborough show.
The all-electric E-Fan 2.0, with a flight time per single charge of about an hour, is slated for the end of 2017, and the four-seater that follows will be a hybrid, using an engine to charge the batteries – meaning that range is only as much of an issue as for conventional aircraft.
Battery technology is moving forward rapidly, propelled by the consumer electronics and automotive markets, and there is huge potential for aircraft as that technology improves. As Sébastian Remy, head of innovation at Airbus, tells me, the goal is clearly hybrid airliners.
As far as the speed of air travel is concerned, supersonic will return. Lockheed Martin’s successor to its SR-71 spyplane of the 1960s is planned for about 2030, and should be capable of Mach 6, or 4,500mph. The technology is there to be repackaged into passenger-carrying planes. And engineers, at Nasa among other places, are working on ways to quiet the sonic boom. Put those two together, add the potential that US company Aerion sees for the latest version of its planned supersonic business jet, and speedy airline travel seems likely.
In the longer term, the trajectory of transcontinental travel could be steep. Spacecraft of the type developed by Elon Musk’s SpaceX are reusable and can land vertically. That is a boon for his Mars plans, but could revolutionise travel around the globe too. A flight from London to Sydney, say, could describe a parabolic arc to the edge of space or beyond, cutting the journey to four hours or less.
Meanwhile hybrid power for helicopters could serve to minimise the most oft-quoted irritant when they fly into city centres – noise. Switching to electric-only mode for approaches and departures could open up new city-centre sites for heliports and thus revolutionise travel.
One can discount any return of radical ideas such as the 1931 plan for a rooftop set of runways at King’s Cross in London. Safety fears over what would happen if an aircraft fell off the edge are just one reason for this proposal’s demise. But a heliport needs only a small footprint and neighbours who are not outraged by a noise nuisance.
And the timescale for all of this? One hundred years ago flying was all about wood and canvas aircraft, and frequent crashes. Aviation today is almost unrecognisably changed: another century from now, the picture will certainly look as different again, though rocket belts are still, regrettably, not likely to be an everyday item. One can only hope that airport security screening makes as much progress.