The Science Of The Next 150 Years: 50 Years in the Future
When the U.S. civil aeronautics administration certified the Aerocar for operation in 1956, it seemed inevitable, at least to aerospace engineers, that before long the flying car would take its place as a fixture in the garage of the typical suburban ranch home. Yet that was not to be. The Aerocar, which looked like a car but had wings and could take off on a short runway, was too expensive to justify mass production. Aerocar International built only six of these vehicles, leaving the promise of the flying car unfulfilled—except in episodes of The Jetsons.

More than 50 years later the flying car is making a comeback. Two models have completed one or more flight tests. The Transition, built by Terrafugia in Woburn, Mass., is a Light- Sport aircraft with foldable wings that can carry two people, plus luggage. To fly, you first need to drive it to an airport (it requires a conventional runway). The PAL-V ONE (for personal air and land vehicle), built by PAL-V Europe in Raamsdonksveer, the Netherlands, needs only a little more than 650 feet to take off. It looks like a three-wheeler crossed with a helicopter. Thrust comes from a rear-mounted propeller, and a free-spinning rotor on the top generates lift. Both cars cruise below 100 knots and have a decent range on a tank of fuel (450 miles for the Transition; about a third lower for the maximum range of the PAL-V).

Neither car, however, is going to fulfill the promise of bringing flying vehicles to the masses. Even if the manufacturers were able to bring down the anticipated $300,000 price tag for both to more affordable levels, the market is limited because of the prospect of hordes of private aircraft going from road to air and back. Airports have enough trouble today coordinating the comings and goings of a few thousand jets. If every car could fly, the skies would be in chaos.

Currently pilots of flying cars can take advantage of the relatively new Light-Sport category; these aircraft can be flown by anyone with a valid driver's license, no major medical conditions and a Sport Pilot certificate (which includes a requirement of only 20 hours of training). The Sport Pilot category keeps pilots out of congested airspace, for good reason, and limits operations to personal use: no business can be conducted under this license.

This method of certification works only because there are relatively few people who fly their own personal vehicles. If drivers were to take to the skies in significant numbers, the congestion would become dangerous. Flying cars will continue to service small niche markets until they can be truly integrated into the national airspace.

To achieve the kind of transportation breakthrough that will lead to a plane in every driveway, we must let go of our need for control and let the plane do the flying for us. Personal and commercial air vehicles will have to be more like unmanned aerial vehicles (UAVs), or drones.

In the military, personnel who are not certified pilots operate drones. Indeed, one of the most attractive qualities of drones is that they save the military from having to devote a great deal of resources to training pilots.

Drones today have enough smarts in them to go where they are commanded, and research now under way will endow them with enough humanlike reasoning to be able to respond to emergency situations on their own. This same vision is behind Google's robotic car. And given the problems with driver distraction and our predilection to talk, text and eat while driving (and flying), a car that both drives and flies itself may mean safer transportation in the future.

Many technological challenges stand in the way of achieving this vision of a commercially available and economically viable passenger-carrying drone. We will have to establish reliable and safe communications networks and robust autonomous flight controls to guide flying cars along their airborne routes.

We will also have to integrate these operations as part of the national air-traffic-control network—perhaps the most formidable obstacle to creating a nationwide personal air-transport system, given that numerous attempts at overhauling the present air-traffic system have been stymied repeatedly. The basic technology building blocks are there, however. Recent experience with controlling the operation of drones around the globe may provide a model for personal air travel five decades hence. Now we have to figure out how to put all the technological pieces together.

In 2010 the Defense Advanced Research Projects Agency started a program, called Transformer, to build a four-person road-worthy vehicle capable of vertical takeoff and landing—essentially a passenger-carrying drone—that a typical soldier with no aviation background can operate even more easily than existing drone technologies. darpa expects to fly a prototype during the next few years. With this progress in drone technology, together with commercial personal aircraft such as the Transition and PAL-V—the most advanced implementation of air-road vehicle technology to date—we may well see within the next 50 years the vision of an airplane in every driveway. The George Jetson of 50 years from now will be riding in a drone.

TO WATCH A FLYING CAR VIDEO: ScientificAmerican.com/jan2013/flying-car