FROM THE ARCHIVES
Let’s Get Airborne
Electric aircraft are beginning to pop up in many different guises around us as battery technology becomes more suitable for aviation.
The technology is based on the helicopter principle of horizontally mounted propellers and generally manifests in a configuration of four propellers on the corners of the vehicle, called a quadropter or quadrotor. The aircraft is considered stable, quite fail-safe, and easy to manoeuver—more so than a helicopter with its single propeller. The lifting capability of a vehicle of this type is impressive too, which is handy when it is designed to be small yet carry cargo.
Even passenger drones are being developed, with the justification that they would not require pilot licenses when remotely controlled or autonomous, thus making them a viable transport option for almost anyone, regardless of whether they can steer an aircraft or not. Given the state of congestion we deal with in cities, this kind of “flying taxi” would be a welcome relief to the hordes of commuters and others who need to get from place to place on a daily basis. And given the high speed and direct routes of air travel, passenger drones could hugely extend the habitable range of cities, potentially turning villages hundreds of kilometers away into viable places of residence for those needing to commute to cities for work.
The problem with drones though is that they have high energy requirements, since they have to continuously maintain air columns beneath themselves to stay airborne. Keeping a drone in the air is heavy work for four motors, which naturally limits battery life. While this may not matter in a future where electricity comes from entirely renewable resources, it does matter in a present where we still pay for electricity and recharging batteries takes time—too long perhaps for the technology to be readily accepted by the public so that vehicles like these can really take off on a large scale.
There is a good reason why passenger aircraft are not usually based on helicopter technology, but glide on wings: it is significantly more economical, and faster. It is possible to cover far more distance with less energy in an airplane than in a helicopter. This is due primarily to the airplane’s ability to stay airborne with the help of its wings, as well as the comparably lower effort of its motors and consequently lower energy consumption. Airplanes do not need to build up and maintain an air column beneath them.
One newly developed, electric aircraft that uses this advantage is the German Lilium Jet, pictured above. It can take off and land vertically, like a drone, but utilizes wings to glide at travel altitude, thus economizing on battery charge and achieving very respectable speeds at an impressive range.
There is nothing a passenger drone can do that the Lilium Jet can’t— with the exception of landing in a space the size of a car; the Lilium’s wings do stick out. Still, as long as it is used by people who have lots of space, this should be fine. A vehicle for the masses may need to have this aspect revised—perhaps a jiffy with folding or turning wings rather than rigid ones.
The vehicle is full of interesting solutions. It doesn’t use propellers, but clusters of small, independent turbines that would remain unaffected by possible failures of the neighboring engines; this is certainly a reassuring feature, especially if it came to be used in an autonomous vehicle. I’m not sure about you, but if I were to embark on a ride in an aircraft I could not control, and in which there was no pilot to shake awake or stewardess to cling to if things got turbulent, I’d be happy to know things like, If an engine fails, there are twenty more.
Wonderful as all this may be, the “airplane-ification” of the world is still very much uncharted territory and most likely will bring a host of problems before the bold vision of getting everyone airborne (even if it is electrically and autonomously) is realized.
The main problems I currently envisage concern things like collision avoidance between aircraft, airspace usage regulations, privacy, crime, and safety.
I do believe that all of these can be solved. However, since legislation tends to be reactive to facts and does not usually take into account the possibility that there may be emerging solutions to current problems and threats, it is probably high time for people to take on board the vision of a world in which many more of us will be airborne on a regular basis, especially if we don’t want governments to start outlawing our wonderful, new ideas. This has happened. For example, some Chinese cities have now outlawed the otherwise excellent electric scooters and motorcycles that have been in use there for over a decade because their utter silence is a safety risk to pedestrians. How petty! Let us hope this will not happen to those magnificent men in their flying machines.
There also really needs to be development efforts in other areas now to allow for a future of proliferating low-flying, electric aircraft. We need systems that will steer these machines clear of power lines and out of the approach path of commercial aircraft, as well as out of each other’s way. I believe we have the technology for this already, and it can and should be part of the development of the aircraft themselves.
Another factor is ensuring compliance with aviation regulations and airspace use. In essence, the challenge is to make sure the aircraft are never in a place they shouldn’t be, and the necessary no-fly zones, which would need to be recognized automatically, will have to be established. This is nothing that a good GPS and some software couldn’t take care of, but imagine the negotiations at the beginning, and all the emerging requests to create (and delete) no-fly zones. The proliferation of small, low-flying aircraft has the potential to produce the biggest, global, never-ending courtroom drama the world has ever experienced. Our civilization does not currently accommodate the possibility that your neighbor may see you sunbathing in the nude behind your hedge because now he has an aircraft! Architecture will change because of this.
Heists and prison escapes will take on a whole new dimension too, once gangsters can conveniently get away in a flying taxi with floral patterns and “I run on solar” stickers plastered all over it. This could extend to terrorism, human trafficking, and illegal border crossings as well. The get-away speed and range after a crime or attack would increase so much that the tracking and policing of vehicles would have to be thoroughly rethought.
And finally, there is the safety aspect. It is fine that some aircraft are nearly fail-proof. But what about the ones that do fail? A failing car is easily dealt with, since most of them will simply come to a sputtering halt somewhere by the side of the road; and you know you are safe from cars as long as you avoid roads. But what about passenger drones and other personal aircraft? At 300 km/h, coming from any direction in the sky, something could hit you anywhere, anytime, even in the middle of nowhere. This will bring up a multitude of issues, and urban planners and architects may be well-advised to consider how the city, the suburb, and the village of the future may need to look to ensure pedestrians stay safe in them.
But now that all these dark thoughts are out of the way, I say, let’s do it! It’s the coolest thing yet.