When it comes to airport infrastructure, the design of terminals may have changed over the years, but the long, straight runway has stayed remarkably consistent. Dutch researcher Henk Hesselink thinks it’s time for a change. His radical ideas about runway design would transform the modern airport’s operations, layout, and efficiency—and even its architecture.
Since 2012, Hesselink and his team at the National Aerospace Laboratory (NLR) in the Netherlands have been working on a runway design that’s circular instead of straight. Their so-called Endless Runway Project—funded by the European Commission’s Seventh Framework Program, which supported research in breakthrough technology from 2007 through 2013, and in partnership with several other European scientific agencies—proposes a circular design that would enable planes to take off in the direction most advantageous for them. Namely, the direction without any crosswinds.
As Hesselink tells Co.Design, crosswinds are exactly what they sound like: Winds that buffet an airplane from the side as it lands. He was inspired to create a new kind of runway while watching “scary” landing videos online, which show crosswinds in action. (Though he says it looks scarier than it actually is: This kind of movement is fairly normal based on the way landing occurs with current runway design.)
When crosswinds are light, they have no impact on taking off or landing, but when they’re too strong, runways facing perpendicular to the crosswinds have to be shut down entirely—which can seriously impact not just one airport, but the entire network. It’s something that happens frequently near the ocean. For instance, Hesselink says that the Amsterdam airport often has to switch between runways during durations of bad conditions, and in smaller cities with fewer runways, crosswinds can grind all flights to a complete halt.
But the circular runway system that Hesselink designed, with a diameter of about 2.2 miles and circumference of about 6.2 miles, can accommodate two planes landing simultaneously even when there are bad crosswinds. That’s because there are always two areas on the ring where the crosswinds will be aligned with the direction of takeoff. In good conditions, three planes can land and take off simultaneously.
The circular runway works almost like a high-speed racetrack or roulette wheel, Hesselink says. If the circular runway were completely flat on the ground, the centrifugal forces would be too great and push the plane off the runway. But his design is slightly banked, meaning it’s slightly raised on its outer edges to keep the plane on the runway as it gains speed.
To see how the design would hold up at a major airport, Hesselink and his team took the flight patterns from France’s Charles de Gaulle Airport, which has four runways, and used a computer simulation to prove that the circular runway could handle the same number of departures and landings. It’s also more efficient in terms of runway space: Though the circle’s circumference is roughly the length of three standard runways, it’s able to handle the traffic capacity of four. And since landing airplanes wouldn’t have to fight strong crosswinds, airlines would save on fuel, too.
For now, the Endless Runway remains a concept where the only testing has been within the safe confines of computer simulation. But Hesselink hopes to test the idea in real life on a racetrack with a drone. If it’s successful, perhaps new airports—especially on small islands with limited space—will adopt the design. Hesselink says it’s unlikely that any existing airport would be able to implement it, since it requires a radical shift in infrastructure.
One added bonus of changing runway design? An entirely new set of architectural considerations—that could conceivably lead to a renaissance in airport design. It also looks cool from above; airports would look like giant circles from the air. “It’s aesthetically a nice airport,” Hesselink says. “It looks better than the current ones, if I can be so modest.”