The flying car – science fiction or science fact?
From Chitty Chitty bang bang, to Doc Brown’s time-traveling DeLorean, it has been a long-standing dream that one day flying cars will be the primary choice for personal transport. In the last few months or so we have seen an explosion of discussion around this, I was even recently invited by Peter Campbell, Motoring Editor, Financial Times, to give a speech at the FT’s Future of The Car Summit to answer the question: ‘The Prospects for the Flying Car – Science fiction or science fact?’
Here’s my take on it all.
Where are we currently?
Drones and helicopters may seem very different flying machines, however, they have very similar attributes. Both are extremely good at taking off and setting down in confined spaces due to their propulsion systems, however, they are a lot less efficient at cruising over distances. While drones have demonstrated the ability to make low-cost flying machines perfectly controllable for everyone, helicopters have proved that this can have limitations particularly regarding the costs when used for personal flight.
A dual-mode approach with vertical take-off and landing and fixed wing cruising helps efficiency over distance but adds weight, and mechanical complexity – requires more energy, more fuel, and costs. So unless we can get to solutions that are cost-effective, quiet and emit very little CO2, are safe, reliable and easy to use – then we are not actually going to solve any of our transport issues.
A flying Leaf
Let’s use the trusty Nissan Leaf to illustrate the point. To do a 100-mile trip (the average number of miles I get to a full charge with my Leaf) while airborne I’d need a lot more energy than on the road, to overcome the forces of gravity and drag. If, theoretically, we had a way to get that car into the air, really efficiently, the energy stored in that battery would be depleted by hovering at 50 ft in under a minute.
To provide the ‘theoretical’ energy to get that approximate two tonnes of vehicle and any passengers airborne and then keep it in the air and fly it 100 miles, would require the equivalent of 500kWh of battery energy – adding about four tonnes in weight. Of course this is a never ending cycle – because I would need much more battery power to provide the energy to lift that additional four tonnes of battery – and things very quickly escalate in a way that we cannot add energy and power fast enough as we add even more weight.
So, will there ever be flying cars?
Well, in some form, and some day, yes of course there will be, but we need to get the definition right.
The notion of a car that looks like a car which at the flick of a switch instantly takes off and flies a la Jetsons, I would say that’s not something that our car or aircraft company planning departments need to get too worried for the foreseeable future. In the end cars and planes are two very separate technologies, that although it is possible to combine, you create something that doesn’t work that well as either.
But future on-demand urban air transport services certainly offers a great deal more potential.
There are plenty of companies racing towards a future of flying cars. One example is Munich-based Lilium Aviation announced an all-important milestone, with the first test flight of its all-electric, two-seater, vertical take-off and landing prototype vehicle. It is powered by 36 separate electric jet engines mounted on 10-metre long wings via 12 movable flaps. The flaps point downwards to allow vertical take-off and then are able to reposition to a horizontal position to provide forward thrust. They claim a 300km range, 300km/h velocity and less noise than a motorcycle.
Others such as Uber and Airbus have proposed projects in the near future that test their concepts in the race to achieving the personal mobility in the air.
So how do we do it?
We must still overcome the self-same issues that the automotive and aerospace industries are trying to overcome today.
We need to continue to develop battery performance with significant improvements to cost, weight, package, charging times and so on. Advanced lightweight technology, and improvements to electric motors and power electronics are also essential for the automotive industry today and to set the foundations for a future flying car industry.
Beyond propulsion, autonomous vehicle technology will be a game changer. It is expected it will revolutionise ownership models, usage models and usher in seamless end-to-end transportation. These will show the way for the required regulatory frameworks as well as de-skilling driving, and ultimately de-skilling flying, making both safer to the point where flying personal mobility could well be accessible for many.
In the UK we have a long tradition of invention and innovation. Rebuilding the UK automotive supply chain in the advanced, next generation technologies – advanced batteries, motors, power electronics and range extenders – Is a critical mission for the Advanced Propulsion Centre and the UK car industry.
We are a nation of inventors and if the flying car is really going to be a next generation of personal transport someday then the UK will most definitely be the place to start the search.