A Czech engineer has gotten roadworthy approvals for his gyrocopter prototype, the GyroDrive.

20170717_EDNA_GyroDrive_Nirvana-Autogyro (cr) Figure 1: The GyroDrive combines a gasoline-powered gyrocopter with an electric-powered three-wheel motorcycle. (Source: Nirvana Autogyro)

The GyroDrive, developed by Nirvana Autogyro owner Pavel Březina, uses electric motors for ground propulsion. Březina has successfully flown and driven the prototype, which, unlike all the other flying car schemes, Březina has actually gotten a road certificate in the Czech Republic.

Aside from Březina, PAL-V Liberty has been working on a road-able gyrocopter since 2001. The group has a working prototype since 2012. Since it is a 3-wheeled vehicle, it only has to pass motorcycle safety and pollution regulations. There is no crash-testing, which would require a structure with much more weight along with air bags and other design hurdles.

Like a lot of great engineers, they may be reaching for a bridge too far. It’s not only a trike, but a tilting trike. Rather than just lash the rotors like Březina does, it electrically lowers the whole tower and then the rotors can fold back in a method they do not disclose.

More germane to the flying car is the Moller Skycar. Paul Moller made $25 million when he sold his SuperTrapp motorcycle muffler company. He proceeded to plough that and much more into a 50-year development of a flying car. Like many impractical projects, there was always another key thing needed. After a while, he said he needed to develop a new rotary engine to get the specific power needed for the car. Then it was computer control to keep the thing stable. Moller has never made a vehicle that flew in untethered flight. Eventually he announced a new design, the M200G Volantor. The TV show Mythbusters estimated that Moller has spent about $200 million on the Skycar.

Terrafugia, meanwhile, promises to have a vehicle you can buy in just a few more years. To their credit, they did fly a prototype in 2009. Despite not making anything to production, like Moller, the company recently came out with a new model, the TF-X.

With the advent of electric drones, many people are trying to scale them up for human transport. Amongst these is Google co-founder Larry Page, who has spent $100 million, but at least his flying car is supposed to come out in 2017.

Perhaps more appealing is the Aeromobil flying car. It’s another complex product with an introduction “just around the corner.” It’s pretty and swoopy, and they claim to be legal in most countries. As a four-wheeled vehicle, it has to pass crash tests, safety tests and roll-over tests. That is a monumental task just for the bureaucratic nightmare you have to navigate. The real killer is all the weight you have to add. That weight makes everything larger. A pound of payload adds 5 pounds total, even if that payload is airbags or crush structures. Like so many of these schemes, you can pre-order it in 2017.

At least the folks at Jetpack Aviation have brought a jet-pack product to market. Now they want to hang six electric motors on top of a helicopter cabin and fly through the air. The problem is that it’s not a flying car, it’s a VTOL (vertical take-off and landing) aircraft. It is also a rotorcraft, like any other helicopter. Expect a few miles per gallon, or very short battery life. Another major problem is safety under motor failure. With one out of six motors failing, it will be very difficult to keep stable. That is to say, you will crash and die. Designs with four rotors are even more dangerous. Be sure the payload spec is great enough to carry a ballistic parachute.

Realising the danger of motor failure, some inventors are using many more motors. The Swarm hovercraft has 54 motors. Another hovercraft with many rotors sits the pilot above the rotors, instead of hanging below them as in the Swarm. This one actually flies, and has solved the battery problem by using a internal combustion engine for power.

Government-owned Airbus, meanwhile, has a flying pilotless taxi in the works. It’s VTOL, but has airfoils so it gets decent power consumption once under way. Thing is, the transition between hover and forward flight is a complex problem, just ask the Harrier engineers, designers of the most crashed jet in the U.S. military. Airbus claims it will fly prototypes by the end of 2017.

Even if these companies beat the weight, complexity, battery, safety and software issues, there still is the problem of cost. Those gyrocopter cars will cost about a half-million dollars. And they have the simplicity of an inherently safe flight mechanism combined with the much easier regulatory environment of a motorcycle. The bigger, heavier, more complex vehicles are sure to cost over a million dollars. They will probably be closer to a private jet, at multi-millions of dollars. As to taxi service, a taxi is based on the capital utilisation of a $30,000 car. When the car is two decades (×100) greater cost, that is a bill very few can afford. The flying lawn chairs are more affordable, but they are still unproven and very dangerous.

Engineering is the Venn diagram of science and economics. MIT grads like at Terrafugia are focused on the science, but not the economic realities of designing an airplane and a car combined into one vehicle. The companies proposing million-dollar taxicabs are ignoring the problem of capital utilisation. You have to pay for depreciation of that vehicle, as well as exorbitant operating and maintenance costs. So if you are waiting for a VTOL flying car autonomous drone taxi, don’t hold your breath. I sure won’t.

First published by EDN.