Flying Car Contenders
Combining a car and an airplane into a single vehicle has proved to be an elusive dream. The convenience of a so-called flying car goes unquestioned, but the technical challenges are immense. It seems that the flying car is eternally 5-10 years away from reality. Each of the latest crop of would-be flying car manufacturers thinks that they have the necessary secret sauce to bring the flying car to life.
The idea of a personal air vehicle, whether it is a personal jetpack or a flying car, has never failed to grab the public's attention. The flying car is especially enticing, conjuring up a convenient personal transport that avoids congested roads by rising above them. Movies and computer games regularly show such vehicles, such as "The Fifth Element" and in the James Bond film "The Man with the Golden Gun." Reality, however, proves a little disappointing with a dearth of such machines.
The challenge of a combined roadworthy and airworthy vehicle is immense. Legally, the vehicle has to satisfy two disparate sets of safety requirements for regulatory bodies of the roads and airways. Technically, the vehicle has to generate enough lift in flight to counter its weight. The most efficient method to generate lift is to use wings, but the wingspan to support the weight of a typical car would be impractical on the open road. The propulsion system for a low-speed airplane favors a propeller over a jet, which raises safety issues while on and near the ground.
Still all is not lost; there are a number of entrepreneurs, engineers and dreamers who believe it is time for a flying car. Solving what seem like intractable problems is what gets these people out of bed on a Monday morning. Some of these pioneers are discussed below.
Moller, founded by Paul Moller, is one of the few companies to have flown a test vehicle (albeit tethered), having progressed through a series of working concept demonstrators - they've even tried to sell test vehicles to the public through eBay. Their latest concept, the M400 Skycar, uses 4 ducted fans, one mounted on each corner of the vehicle for propulsion. Like the V-22 Osprey, the fans rotate around a horizontal axis to allow vertical takeoff and landing. Recent concept pictures of the Skycar show it has sprouted foldable wings to more efficiently generate lift in forward motion. The ducted fans are powered by patented high-efficiency Wankel rotary engines.
The Skycar is a car in name only; it is designed to taxi short distances on the ground and takeoff and land in confined spaces using its vertical takeoff and landing capabilities. In essence the Skycar is the embodiment of a true flying car - you take off and land with minimal time on the ground.
Milner Motors' AirCar is a roadworthy concept design with folding wings. Milner Motors is headed by the father and son team of James (founder) and Chris Milner. Their design uses twin rear-mounted ducted fans for propulsion while airborne and a separate small engine for earth-bound locomotion. It appears to be a simplified version of the Moller M400 Skycar. Currently there are virtual renderings and a non-flying but drivable mockup of the AirCar.
Terrafugia was founded by MIT graduates and is advised by Mark Drela (the MIT professor behind XFOIL) to pursue their idea of a flying car called the Transition. Folding wings, twin tails and a rear mounted propeller for propulsion characterize this "roadable Light-Sport Aircraft." After performing extensive Computational Fluid Dynamics (CFD) simulations and wind tunnel tests, Terrafugia is currently constructing their first physical concept demonstrator. In a novel move, they are also offering free flights in a virtual model of the Transition within the X-Plane flight simulator.
The Magic Dragon Aircar from StrongMobile is Richard Strong's concept of a "roadable aircar." Working on his concept design since the 1960's, Strong has produced a detailed business plan and schematics. The basis of his concept is a front mounted ducted fan and a lifting body. A lifting body derives lift not only from wings (as in a traditional airplane) but also from the shape of the fuselage too, thus increasing the vehicle's overall aerodynamic efficiency. Progress through wind tunnel models and scale models has resulted in a full size non-functioning mock up.
Who is likely to succeed? Call back in 5-10 years to find out. Can't wait that long? Then track progress at the annual unofficial flying car "show and tell" during EAA AirVenture Oshkosh.
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