Runways... OF THE FUTURE!!!!!!

[Graham Kennedy]

http://www.treehugger.com/aviation/circ ... noise.html

Airports take up a lot of room that could be used for other productive purposes, and often their runways do not align with the wind direction, making landings difficult. But Designboom shows us what might be the answer to the problem: make the runways into a big circle. Designboom notes that " that making runways ring-shaped can have a positive environmental impact. since planes will not have to compete with strong cross winds, they will burn less fuel in the area around the airfield. " They are also much smaller.

The idea, from Henk Hesselink of the Netherlands Aerospace Centre, is in the news thanks to a recent BBC video.

Interesting idea. Makes sense, when you think about it. You could take off in or approach from any direction, for one thing.

[IanKennedy]

Interesting concept. It would have to be of sufficient radius to make the curvature not a problem. You are talking about high speeds and effectively what is a tripod landing on it.

[Mikey]

That's what I was thinking. The required radius would seem - without having done the math, just by eye - to obviate the whole point of the thing.

[Graham Kennedy]

Here's an article that has a couple of numbers.

They reckon to make a runway with a diameter of about 2.2 miles and circumference of about 6.2 miles. They say it can accommodate two planes landing simultaneously, even in bad crosswinds. In good weather they say three planes could land simultaneously.

He banks the runways slightly, like an oval racing track, so the planes aren't sliding off as they constantly turn.

The space savings don't come from comparison to a single runway. Rather, as the article says "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."

If the circumference is the same as three runways, then the diameter must be roughly the same as a normal runway.

[Mikey]

I don't buy the bit about

wouldn’t have to fight strong crosswinds.

Perhaps not compared as antipodal to the radial momentum; but at any given instant there could be a very strong crosswind acting against the plane's linear momentum.

[McAvoy]

Looking at it from a aircraft mechanic's perspective, there shouldn't be that much of an issue. However I do wonder over the long term how much stress that would put on the landing gear while taking off and landing.

I guess all of the parking would be under the terminals.

[Bryan Moore]

Looking at it from a aircraft mechanic's perspective, there shouldn't be that much of an issue. However I do wonder over the long term how much stress that would put on the landing gear while taking off and landing.

I guess all of the parking would be under the terminals.

In stock car racing, a race at a "flat" track (<12 degrees banking) will lead teams to adjust the car's camber to help ease the left turns. The down side being, the more camber the car has, the more of a wear it is on the tires and more stress on the suspension. It's not uncommon for axle/rear arm failures. Obviously that is a more extreme situation than planes landing, but I would imagine there would be a certain adjustment from a mechanical perspective, however minor.

[Mikey]

Of course, then the plane so adjusted can't land anywhere with a straight runway, or one with a different radius.