If researcher Henk Hesselink of the Netherlands had his way, circular runways wouldbe everywhere. Hesselink has been exploring the idea for at least five years now and has used commercial flight simulators to prove the viability of the concept. And there are certainly good reasons to explore it further, though it’s not likely to happen. While we don’t expect to start landing in circles anytime soon, strangely enough, the idea has been resurfacing again and again for nearly 100 years.
A Popular Science article published in June 1919 suggested building sloped, circular runways on top of skyscrapers to allow business people to fly straight to their offices in big cities. The idea has come up several times since then, most recently with Hesselink’s Endless Runway project. His research has received funding from the European Commission and was recently the subject of a short BBC video.
Taking off and landing on a circular runway sounds ridiculous, right? Here’s the interesting thing: The concept was successfully tested well before Hesselink began running his simulations—by almost half a century.
The Chicago Tribune put out a piece in 1965 (December 4) reporting on completed Navy testing proving the concept of circular runways to be sound. According to that article, the Navy tested it “with single-engine pistons, single-engine jets, and a four-engine piston transport” and found it “suitable for planes with landing speed of 130 to 150 knots.”
Both the Endless Runway Project and the old U.S. Navy report bring up the same benefits to this unconventional approach. These include needing less space than conventional airports, allowing for any combination of straight-in or circling approaches, and always being able to land or take off with a direct headwind.
There are numerous downsides as well, and not just in terms of cost or new training methods—the ’65 Navy report did mention that they expected resistance to the concept from pilots since a circular runway would require learning new landing techniques, including rolling out into ever-changing wind direction. One wonders, though, how much tire wear the circling landings would result in, bearing in mind that nothing on a commercial jet was designed with the expectation of anything more than minimal sideloads.
Yet, if nothing else, exploring the idea of circular runways might get some aviation types to think about flying differently. To ponder it, if you will, in a non-linear way, though they run the risk of going in circles in the process.
Learn more at the Endless Runway project.