Pilots and plane people, circular banked runways?

[masraum]

Lots of naysayers. Interesting idea, but certainly seems like if the problems could be solved, then it may be efficient. Still, seems like there are LOTS of issues to get past.

the Endless Runway



Think again: Will circular runways ever take off? - BBC News

[rwest]

So cool, love stuff like this. Completely different thinking that really makes sense and in theory, you wouldn't run out of runway so if the plane couldn't brake it could just go around until it stopped.

Like most things, there are probably some negatives to this approach (see what I did there!) I wonder what the cons are?

[wdfifteen]

You would need a straightaway to "shoot" off the runway. As the plane goes faster in a circle, the lift increases, but so does the effective weight. The lift has to overcome both gravity and centripetal force.

[Por_sha911]

It would seem to me that landing on a circular runway would be a nightmare-especially when there are cross winds. Also, the example pictured above means that you have all your eggs in one basket. One problem plane and the entire airport is shut down.

[masraum]

Originally Posted by Por_sha911

It would seem to me that landing on a circular runway would be a nightmare-especially when there are cross winds.

No crosswinds in a circular runway. You have the planes land at whatever direction the wind is going/coming. I think that's one of the pros. No matter what direction the wind is going, you can always land in the right direction to not have crosswinds.

Also, the example pictured above means that you have all your eggs in one basket. One problem plane and the entire airport is shut down.

Yep, that's one of the cons listed in the BBC article.

[masraum]

Originally Posted by rwest

So cool, love stuff like this. Completely different thinking that really makes sense and in theory, you wouldn't run out of runway so if the plane couldn't brake it could just go around until it stopped.

Like most things, there are probably some negatives to this approach (see what I did there!) I wonder what the cons are?

Yep, thinking outside the box is cool.

THe BBC article had lots of cons. The 'Net is full of interesting articles about this guys proposal.

[matt930s]

Here's a good counterpoint article:

Why the circular runway concept wouldn't work - Business Insider

[Embraer]

Crosswinds, mechanical failure, snow removal, instrument approaches, etc. no thanks

[McLovin]

[id10t]

Nascar drivers have a new second career as take-off and landing pilots (like a pilot for a particular harbor, etc in a nautical sense)

[red-beard]

Originally Posted by wdfifteen

You would need a straightaway to "shoot" off the runway. As the plane goes faster in a circle, the lift increases, but so does the effective weight. The lift has to overcome both gravity and centripetal force.

Nope. Need to re-think that. Lift only has to overcome the weight. The issue is the application of rudder, which might require more thrust.

The real problem with a runway like this is that you want to take-off and land against the wind. Going in a circle you could rapidly gain or lose effective lift as your angle to the wind changes.

[masraum]

Originally Posted by id10t

Nascar drivers have a new second career as take-off and landing pilots (like a pilot for a particular harbor, etc in a nautical sense)

Great, now we'll have drafting and "rubbing is racing" and donuts when they successfully land.

[svandamme]

On a normal runway, if the head wind drops or the rate of descent is variable, or there is poor visibility, low ceiling, at worst you come down 500 meter past the point where you normally touch down.
Still plenty of runway left to stop the plane.


How are they planning to do that on a circular runway?
come out of the low ceiling and then say, aw shucks, i missed my turn
There is less safety margin.

[wdfifteen]

Originally Posted by red-beard

Nope. Need to re-think that. Lift only has to overcome the weight. The issue is the application of rudder, which might require more thrust.
.

The video shows a banked runway. The wings not only have to pull the plane up against gravity, but they have to effectively decrease the diameter of the circle against centripetal force.

[petrolhead611]

Float planes use a semi circular take off run when the into wind direction on the lake has insufficient space to allow safe build up to lift off.It is great fun circling at 50 mph or so( Cub speed)

[recycled sixtie]

It is an interesting concept but large aircraft depend on reasonably constant direction of winds for take off and landing. Takeoff and landing performance is improved in a linear manner into wind.

Plus the extra load on one set of tires is not desirable due overheating. Increased risk of blowouts.

Having a banked runway increases the risk of dinging a wingtip.

[widebody911]

This was on reddit a while back

https://www.reddit.com/r/AskEngineers/comments/605yly/circular_runways_is_this_a_realistic_idea/

https://www.reddit.com/r/aviation/comments/5zoa5k/think_again_will_circular_runways_ever_take_off

[Chocaholic]

Seems like a solution to a problem that doesn't exist.

[URY914]

Originally Posted by Chocaholic

Seems like a solution to a problem that doesn't exist.

Agree. What city will be the first to dump a billion $$$ into one and find out it won't work?

[Seahawk]

NAS North Island in the 1930



I was stationed there in the 1980's - things had changed