Flying into the Future

Sorry Ryanair, we have rocket cars now

When previous generations dreamed of modernity, ideas of hoverboards, flying cars, and teleportation devices dominated the collective imagination. Evidently, our future has failed to live up to these eccentric expectations, and people increasingly dismiss such ideas as juvenile fantasies from a bygone era. Yet this reductive view does not seem to have reached the visionaries at SpaceX and Tesla, whose 16 October announcement revealing the world's first flying car.

“We already put the Roadster in a rocket. Now we put a rocket in the Roadster” is one of the many statements Tesla is using to introduce its new creation. Further descriptions present the design as otherworldly and futuristic, drawing heavily on the aesthetics of space exploration. From gold-glazed windows “designed to mimic the copper coating that gives spacesuit visors their gold radiance,” titanium accents which “embody space-age design,” and Ano White paint taking “inspiration from aerospace techniques that provide UV and cryogenic protection when exposed to the harshness of space,” every detail reinforces this futuristic aesthetic. But this is all merely embellishment intended to highlight the true feature setting the Roadster apart, which is, of course, its rocket thrusters. Not only is the vehicle “gravity defying,” but it goes “beyond the limits of physics.” With such extraordinary claims, we seek extraordinary explanations; so what engineering lies behind these remarkable capabilities?

The answer lies in the cold gas thrusters, a technology borrowed from SpaceX that harnesses a physics principle we all know: every action has an equal and opposite reaction. When the highly compressed gas stored in these thrusters is rapidly released, it generates a force that propels the vehicle in the opposite direction. In stark contrast to the conventional operation of rockets, which rely on burning fuel to generate thrust, this system achieves propulsion without combustion. Stored in specialised tanks, the gas is released through a system of ten strategically positioned nozzles around the vehicle. These enable the Roadster not only to lift off the ground, but also to move laterally and rotate mid-air.

However, overshadowed by the spectacle of rocket-powered flight lies a potentially more significant innovation: the Multi-Mode Suction System. By drawing air from beneath the vehicle, a region of lower pressure pulls it towards the road, generating downforce capable of holding the Roadster upside down whilst completely stationary. This enhanced downforce improves tyre grip, enabling sharper cornering and faster acceleration that could be widely utilised, even in normal cars. 

But what do these capabilities amount to if their legal use is ultimately prohibited? As it stands, the Rocket function of the Roadster is not approved for public road use, and it is difficult to comprehend how existing road safety and aviation regulations could possibly accommodate such a vehicle. Beyond legality, there is also the question of when we might actually see commercialisation. Production is reportedly not due to begin until 2028, and Tesla’s history of missed deadlines casts further uncertainty. 

Even as these limitations dampen the realistic future of rocket cars, it is impossible not to acknowledge the Roadster as an engineering feat. Time will ultimately tell, but perhaps those visions of the future were not so far-fetched after all.

Image from Wikimedia Commons