[lisper]

Wow, there are so many reasons this is a terrible idea.

1. It doesn't actually solve the problem it sets out to solve (crosswind landings). To the contrary, a circular runway guarantees that if you have any wind at all then you will have a crosswind at some point in the landing. Not only that, but the apparent wind direction will be constantly shifting during the landing, making the landing even more difficult than a normal crosswind landing.

2. Flying in a circle at a low airspeed and at low altitude is absolutely the single most dangerous thing you can do in an airplane. When you are flying in a circle, the outboard wing is moving faster than the inboard wing, and so if you are flying close to stall speed the inboard wing will stall first, resulting in a spin. It is possible to recover from a spin but you have to descend in order to do it. If the spin starts at low altitude there is nowhere to descend to, so you will crash. Spins on approach to landing are one of the leading causes of fatal crashes in small general aviation aircraft.

3. Airport approach and departure procedures are designed around the fact that runways are aligned in particular directions.

[LoSboccacc]

4 a rolled plane to match banking will move sideway in the direction of the lower wing. to correct that the plane will need to touch down pointing outward the circle, then quickly steer to correct

Edit 5 optimal banking changes with speed and all plane takeoff and land differently. More to the point while accellerating for takeoff the plane will literally go everywhere but in the runway direction

[bitmapbrother]

The circular runway is banked so I would assume crosswinds aren't as devastating due to this banking. However, I am curious as to why you so adamantly believe that circular banked runways guarantee crosswinds. Is this based on scientific research that have proven this or is this just a guess?

[lisper]

> I would assume crosswinds aren't as devastating due to this banking.

You would assume incorrectly. The bank is mostly irrelevant. Crosswinds happen when the direction of motion of the plane is anything other than directly in to the wind. If you're turning, your heading is continually changing, and so the relative wind direction will be continually changing, and so you will necessarily have a crosswind component everywhere except at the one point when you are heading directly into the wind. Even worse, the crosswind component will be continually changing as you turn. This is even worse than it seems. Landing in a crosswind involves a maneuver called "cross-control" where you roll the plane into the wind with the ailerons while simultaneously apply opposite rudder to arrest the resulting turn. It's one of the hardest things to do in an airplane. Getting it right is tricky even when the runway is straight and level and the wind is steady. Trying to do it on a curved banked runway, where the wind is necessary continually shifting as you turn, would be a total nightmare.

> However, I am curious as to why you so adamantly believe that circular banked runways guarantee crosswinds. Is this based on scientific research that have proven this or is this just a guess?

I'm a pilot with over twenty years of experience. But you don't have to be a pilot to see the folly of circular runways. It's simple common sense: if you're turning, you can't be heading directly into the wind the whole time.

[LoSboccacc]

most obvious reason: gusts. wind is rarely stable in intensity and direction.

a secondary point: checkout any landing strip https://i.imgur.com/n99YiM5.png

a plane can't pinpoint the landing to absolute precision, even on autopilot. the dark patch should give you an idea on how much ahead/behind a large plane may land under real world condition - all the test they give in the papers are using small planes or even fighters, those can manage precise landing, a 737 not so much

the plane will have to follow the turn until it touches down, and as it follows the turn it'll change it's direction relative to crosswind, with all the implication it entails. few degrees on landing are already enough to need a significant correction.

[ouid]

also, how do you get to your gate?