Travelling from one point to another without waging through noisy, congested roads has become a far-fetched persistent dream of city dwellers. The average hours wasted on the road worldwide is monotonically increasing with little respite coming from tubeways and expressways. This has inevitably affected productive time at work, time with family, money spent on fuel, pollution-related diseases, and a marked increase in stress levels.
For decades, people have nurtured the dream of easy personal flights. From The Jetsons, Blade Runner, Star Wars to Back to the Future, flying cars have been an ingredient of every science fiction’s futuristic fantasy. In the last 70 years, generations of engineers have tested their models and tried to make the vision of flying cars come true.
In the 1940s, when the car and plane were both becoming cheaper and more commonplace, Ted Hall, an aeronautical engineer, attempted to build the first fully functional flying car affordable to the common man. Backed by the then major aircraft manufacturer Convair, Hall created a road car with attachable wings. Despite its initial triumph with 66 successful test flights, its crash landing in 1947 crashed all promises of its commercial success. The project was deemed dangerous, and eventually shut down.
Since then, there have been numerous attempts at building flying cars. Yet we’ve made little progress in taking personal transportation to the skies. Real considerations, including technical complexity, cost, size, dangers, regulations and liabilities have almost always put a damper on it. As a result, till date there are hardly any manufacturers of small light air vehicles.
However, the dream was never given up on. Several companies such as AeroMobil, Terrafugia and Moller International have actively pursued the dream and are working on prototypes of car-size planes that could soon become safe, affordable and versatile enough for ordinary people to use regularly. Reports of Google co-founder Larry Page funding Zee Aero since 2010 is creating a buzz. In 2015, he invested in another firm called Kitty Hawk, which also worked towards the same goal.
Research and development in this field has been capsuled into patents by several companies. Some seminal patents include US20160236774 by Airbus, US20070246601 by The Boeing Company and US20160176256 by Toyota.
An earlier iRunway blog on Flying Cars, published on September 13, 2016 delineates some actual prototypes, including AeroMobil’s and Terrafugia’s flying car designs.
Technologies that are maturing in this domain involve lighter and more powerful electric motors, batteries that can store more energy, and more sophisticated aviation software.
Vertical Take-off and Landing (VTOL) Airplanes
A typical airplane takes off horizontally, building up speed enough for the wings to carry it upward. As a result a normal airplane needs a long runway to take off and land. Vertical takeoff and landing aircraft, by contrast, take off vertically like a helicopter, then switch to flying horizontally once they are in the air. This further allows VTOLs to take off and land in locations which are not conventional for normal airplanes.
Though VTOLs can be dated back to the 1960s and is not new as a technology, they could rarely be practically implemented due to their complexity. The newer prototypes being designed in present times are based on the replacement of internal combustion engines by electric motors that can be much lighter, simpler, powerful, and cheaper. For instance, Zee.Aero filed a patent application (US20130214086 A1) that discloses a tiny, electric-powered aircraft that can possibly comfortably fit in a conventional parking space. [Img Src: Fig. 7A; US20130214086 A1]
The design proposed by Zee.Aero has eight vertical propellers for takeoff, and two in the back to provide horizontal thrust. This is because it takes a lot more thrust to take off vertically than to keep the aircraft moving once in the air. Once afloat, the eight vertical propellers can be turned off to save power. Though having 10 engines can be argued to be inconvenient since it’ll make the aircraft very heavy, Zee.Aero feels that using small, light-weighted electric motors would alleviate the problem.
Apart from lighter and more powerful electric motors, the next thing that is picking up pace in research is improvement in battery technology. With increase in energy density of batteries, electric airplanes can be made lighter and can fly farther with a single charge. The other key breakthrough is developing better software. An airplane with 10 propellers is expected to be too complex for a human pilot to manage. But a well-designed software can easily manage 10 propellers concurrently, supplying power to the propellers in an efficient manner. Redundancies can also be designed around multi-propeller designs such that loss of one propeller might be handled easily by the others. Other examples of multi-propeller/multicopter designs is the Volocopter developed by e-Volo and the two-seater Joby S2 by Joby Aviation.
In 2010, NASA started work on an all-electric one-man VTOL aircraft called Puffin, which claims to have zero emissions and being 10 times quieter than current low-noise helicopters, the only major drawback being its battery capacity.
The combination of smaller, more powerful electric motors, better batteries, and sophisticated software will open up gates for plethora of new design possibilities.
In October 2016, Uber published a whitepaper titled “Fast-Forwarding to a Future of On-Demand Urban Air Transportation” that describes “Uber Elevate,” the company’s vision for on-demand urban air transportation. Uber’s idea is to build a network of on-demand, small electric VTOLs that can hover like a helicopter, but are much more efficient, as well as less noisy and expensive. Uber envisions this to smoothen daily commute from suburbs to nearest cities, as VTOLs become more affordable for masses. With features such as ride sharing/pooling this might become more affordable than owning a car. Just as skyscrapers allowed cities to use limited land more efficiently, urban air transportation will use three-dimensional airspace to alleviate transportation congestion on the ground.
Uber is keen on developing not just a flying car, but an autonomous, self-driven one! Along with a lengthy analysis of the economics and mechanics of flying cars, Uber clarifies that rather than manufacturing VTOL hardware themselves, Uber is looking to collaborate with vehicle developers, regulators, city and national governments, and other community stakeholders.
On the brighter side, since these aircraft can take off and land vertically, they wouldn’t require full-blown airports; they would rather use small “vertiports” that could fit in a suburban parking lot or the top floor of a parking garage. Uber envisions an on-demand model whereby users can book flights with their smartphones. Further, though VTOL aircrafts are likely to have human pilots initially, sophisticated software might soon take over.
While the program claims to radically improve urban mobility, Uber agrees that the vision is ambitious and might take over a decade to achieve. The whitepaper enlists critical challenges, including the Certification Process, battery technology, vehicle efficiency, speed and range, vehicle reliability, air traffic control, cost and affordability, rider experience, safety, aircraft noise and emissions, vertiport infrastructure and pilot training. In the long run, any of these concerns could create a bottleneck for widespread use of the much-desired technology.
Obviously, we’re still several years away from commercial, affordable, on-demand flying car service. But from self-driving cars to inter-vehicular communication, the transportation market has seen much advances in the past few years, and even with respect to flying cars we are proudly beyond the point of idle speculation. With a number of startups actively testing working prototypes, and big companies like Uber assessing the market and gearing themselves to join the run, sometime in the next decade or two, we can surely expect to start seeing tiny, funny-looking airplanes buzzing around in the sky overhead.
(The featured image (repeated above) is a collage created from images that were sourced in clockwise from top left order from https://c1.staticflickr.com/4/3505/3983331817_d4e9c04ac7.jpg, https://upload.wikimedia.org/wikipedia/commons/8/8a/Terrafugia_–_2012_NYIAS_cropped.png, https://upload.wikimedia.org/wikipedia/commons/a/aa/DeLorean_DMC-12_Head_with_doors_open.png, https://upload.wikimedia.org/wikipedia/commons/c/c3/Alfa_spix_creatix.be.jpg, https://upload.wikimedia.org/wikipedia/commons/4/42/SDhpXFV.png & https://upload.wikimedia.org/wikipedia/commons/f/f9/Maverick_Flying_Car.jpg)