Drones vie with supersonics for the future of flight

Paul Marks, senior technology correspondent

 

(Image: David Crump/Daily Mail/Rex Features )

What do you expect of aviation as flight technology advances? More than a century after the Wright Brothers triumphed on a wind-beaten North Carolina beach, aviation researchers have the technology to take flight in any number of directions.

With advanced autopilots and drones as evidence, some are predicting the end of human pilots. Others say hybrid engines and ever-lighter plastic planes are the obvious, green way ahead. Will suborbital hypersonic planes whisk us from London to Sydney in a few hours, or are Zeppelin-like blimps (the aviation equivalent of the slow food movement) about to make flying civilised again with a triumphant comeback?

The Future Skies discussion at the Dana Centre - the sci-tech speakeasy at London’s Science Museum - addressed just these questions earlier this week, guided by a team of flight experts from around the country. Hypersonics expert Ben Thornber of Cranfield, the aeronautical university near Bedford, UK, was joined by uncrewed flight experts Jonathan Masters and Daniel Smith of planes-to-submarines maker BAE Systems of Warton, Lancashire. And the whole thing was chaired by Tim Robinson, editor of the Royal Aeronautical Society’s Aerospace magazine.

Before the discussion kicked off, the audience, a crowd of eager plane enthusiasts, was asked to vote on their highest hopes for the future of aviation. “Faster journeys” was a clear winner, but would they hear anything from the panel that would change their mind?

The speed of achievable supersonic flight topped out at just over twice the speed of sound with Concorde in the 1960s. Nothing even slightly more affordable has approached since that millionaire’s vehicle ran its course and was scrapped. The expense, Thornber explained, comes from fuel costs and tough materials required to deal with the temperatures and pressures of hypersonic flight - if speeds of five times the speed of sound (Mach 5 - or one mile per second) are to be attained.

“I don't believe that there has been a great shift in the cost of high speed flight,” Thornber says. “However, there are now many more wealthy individuals - thus potentially creating a critical mass of customers for niche services. Of course, this also relies on mitigation of the sonic boom problem.” When reminded of the cost and noise factors, and that the richest one per cent would likely be the only passengers, the Dana Centre's audience deflated slightly.

Still, today’s more common flight experience is “a far cry from Wilbur and Orville Wright hanging on for dear life”, Robinson reminded us. We fly in air-conditioned, pressurised comfort with “reasonably nice food”, in-flight movies, duty-free shopping and - increasingly - Wi-Fi and cellphone connections.

But the cost is the emissions. One possible solution is greener “open rotor” jet engines (see video, above), Another is the use of new lightweight materials, if aircraft makers can iron out their persistent problems. Both the heavily composite Boeing 787 and Airbus A380 have exhibited worrying problems, and are right now in for urgent checks.

Smith and Masters cheered the audience's spirits, though, when they talked through some of the exciting non-military applications of unmanned planes. Upcoming civil airspace law changes are about to make uncrewed aircraft something we can all use - whether it's for cargo, pollution monitoring, crop spraying or aerial photography.

One audience member wondered if the panel believed, as some conspiracy theorists do, that it was a large Global Hawk UAV that hit the Pentagon on 9/11, rather than the passenger-packed jet. That absurdity was given short shrift and, back in the land of sense, sensing came up. For this is the biggest issue facing drones: how to sense and avoid crewed aircraft.

“We’re not allowed to fly them over people yet,” Smith said. “Because we’re not very good at it.”

But the technology is coming. In the US, former navy fighter pilot and MIT automation expert Mary Cummings is predicting that cargo airlines will be first  to switch planes to automatic, without pilots. Listen to her speak about the idea on NPR's Science Friday radio programme last week.

As the Dana Centre event closed, another vote was taken. The mood had switched from a wish for sheer airspeed to a clear majority now looking forward to novel pilot-less planes taking to the air - creating new business and employment opportunities without breaking the bank, or the climate.

But don’t get too carried away, said one audience member. “Just in the interests of balance, I’d like to see a UAV land on the Hudson like the US Airways pilot did in that miracle landing. I don’t think it would succeed.”

http://www.newscientist.com/