I received an email this week from a researcher based in Los Angeles, who I wanted to interview. “I hope to be back before 4pm,” it read. “Of course, if I had a flying car I could better negotiate the LA traffic congestion and be back earlier.”
An unusually imaginative response, you might think. In fact it was pretty apt as I wanted to ask him about the future of personal transportation, and the sender was Professor Mario Gerla, who studies traffic congestion, pollution and intelligent transport at the University of California, Los Angeles.
Many of us have wished for a personal flying machine to lift us out of infuriating traffic jams and deposit us on our driveways. With recent advances in materials, power sources, and automation, those dreams may become reality more quickly than many of us realise, as I’ve discussed before. Earlier this month, US aerospace start-up Terrafugia unveiled the TF-X, a concept design for a radical new type of personal air transport vehicle. So I talked to Carl Dietrich, co-founder of the company, to find out how it might work.
“We think this is the right time to start seriously looking at the challenges associated with creating what people call a flying car," he says. "The vision is to try to create the future of personal transportation that people have dreamed about for years." Dietrich believes all the required technology already exists, and that initial discussions with the US Federal Aviation Administration suggest existing regulatory obstacles can be overcome.
Terrafugia is just one of a number of companies proposing personal aviation and it has been taking orders for an earlier design – the Transition, a road-legal aeroplane with foldable wings – for several years. The TF-X design is more futuristic, but is more likely to provide what most of us dream of when we think of flying cars.
One of its main selling points is the ability to take off and land vertically like a helicopter. In car mode, the plug-in hybrid can rely on its electric motors and battery packs. For lift-off it needs extra power from its hydrocarbon combustion engine. Folded winglets are extended. Two huge motor pods on either side of the vehicle are pointed vertically up, and the propellers provide lift. Each pod has 16 independent electric motors, with its own controller and battery pack, meaning a failure is not catastrophic.
When it attains the required altitude the pods start to point forward. A ducted fan at the rear provides thrust and the wings start to operate as a conventional aerodynamic surface to provide lift as it accelerates. At full speed the propellers on the ends of the pods fold back and the vehicle enters “cruise” mode. The TF-X has a maximum speed of 200 miles per hour and a proposed range of 500 miles.
“With electric propulsion we can go to much higher levels of what we call parallel system architecture, so a given failure of a battery, or a motor controller, or even a motor itself, would not necessarily result in total loss of propulsive capability,” says Dietrich. “One of the big advantages of going to electric-powered aircraft is that there is the opportunity to change the system architecture away from what’s been typical in aviation to date where you have one, two, or four engines tops,” he adds.
“It’s definitely an interesting proposition,” says Dr Frank Nieuwenhuizen, Aerospace Engineer at the Max Planck Institute for Biological Cybernetics, and one of the people behind the EU MyCopter project that looks at how the air transport industry might change over the next century. “The vision takes parts of what we think is important for a personal air transportation system, like the vertical takeoff and landing feature for example.”