Circular Runways

[DXB]

What the...??   Imagine this sight picture on final!  Of course if they built it, I would want to try it.  Anyone here bullish on this concept?

 

 

 

[RLCarter]

id still get a x-wind

[mccdeuce]

I'm trying to find the video of it - but tailwheel aircraft have done this many times before... 

personally I think they do it with a little alcohol in their veins.

[mccdeuce]

Also I'm not sure how you work work instrument approaches except for circle to land.

[carusoam]

Expect to fly straight in. Following the rabbit, that would be tangential to the circle. Selected by current wind direction.

They would need to use the rabbit that aligns with the day's wind conditions.

The challenge would be to run out of energy while in a bank, as you become centered over the lane in the circle.

Too much energy, the landing will no longer be aligned with the wind.  the go around can get pretty funky...

Too little energy, you will be sliding down the banked curves like Talledega...

they left out most of the details required...

Everyone enters the pattern flying a standard rate turn and following an AOAi to manage energy..?  The bank is going to be about 15°...

The diameter of the facility is going to be quite large.

Getting used to the higher landing speeds that come with the accelerated stall (bank angle) is going to make some wreckage...  slowflight + accelerated stall.

Do you approach the landing with the wings banked already?  Or do you approach level, then add bank like kicking the rudder to align with the center line..?

Did they have more answers to the tech questions?

Best regards,

-a-

Edited March 18, 2017 by carusoam

[tigers2007]

They would need a lot of approach lighting! Or put the lighting on movable trailers or a rail system.


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[Cyril Gibb]

This "study" was apparently funded by the EU Gov't at the Netherlands Aerospace Centre.  Truly a profoundly stupid idea.  What a waste of taxpayer money.

That could never happen here!

[EricJ]

It would be fun to get some video of a day when the pavement was wet or slippery, though.  

[ArtVandelay]

Airplane version of NASCAR!

[aviatoreb]

1 hour ago, EricJ said:

It would be fun to get some video of a day when the pavement was wet or slippery, though.  

If the banking is corrected for the typical landing speed of a jet and the radius of the circle, then there will be no traction needed.

[aviatoreb]

1 hour ago, EricJ said:

It would be fun to get some video of a day when the pavement was wet or slippery, though.  

If the banking is corrected for the typical landing speed of a jet and the radius of the circle, then there will be no traction needed.

But as Anthony alluded, the problem then would be as the airplane slows to a stop, then traction would be needed to keep it from sliding inward.  But I suspect the circle is large enough that even at airplane landing speeds, not a lot of bank is required so traction to hold the bank at slow speeds is not significant.

[EricJ]

Just now, aviatoreb said:

If the banking is corrected for the typical landing speed of a jet and the radius of the circle, then there will be no traction needed.

Any particular bank angle is optimized for one speed, and the range of speed required to take off and land is fairly broad.   The way around that is to make it bowl-shaped, which requires getting the trajectory through the bowl fairly accurately, which won't always happen, especially as traction conditions change due to the weather.   And the tire's ability to provide lateral traction depends on whether it is braking or not, so modulating the brakes would make it even more exciting.

Would be fun times.

 

[aviatoreb]

1 hour ago, EricJ said:

Any particular bank angle is optimized for one speed, and the range of speed required to take off and land is fairly broad.   The way around that is to make it bowl-shaped, which requires getting the trajectory through the bowl fairly accurately, which won't always happen, especially as traction conditions change due to the weather.   And the tire's ability to provide lateral traction depends on whether it is braking or not, so modulating the brakes would make it even more exciting.

Would be fun times.

 

Agreed!

[Guest]

11 hours ago, Cyril Gibb said:

This "study" was apparently funded by the EU Gov't at the Netherlands Aerospace Centre.  Truly a profoundly stupid idea.  What a waste of taxpayer money.

That could never happen here!

Here in Ontario we would fill the infield with wind mills to generate almost free power from the wind.

Clarence

[par]

I think they should have spent the money for this"study" on their current immigration problems instead. What a waste of time and energy.

[tigers2007]

I bet that this is one of the committed projects that the EU is trying to make the U.K. pay their share for before leaving the EU. Hilarious.


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[midlifeflyer]

It would work better on a treadmill.

[PTK]

8 hours ago, par said:

I think they should have spent the money for this"study" on their current immigration problems instead. What a waste of time and energy.

Or reimburse the American taxpayer for defending them. The NATO guidelines for defence expenditure as a percentage of GDP is 2%. The US taxpayer carries the burden with double that, just under 4%. Only a few NATO member countries follow the guidelines: US, UK, Greece, Estonia and Poland. All the rest fall considerably below. The Netherlands where this guy is from is down at just over 1%!

It's real easy to waste money when it's not yours, isn't it Mr. Hesselink?!

[Yetti]

NASCAR goes about the same speed as jets taking off.   Look at the banks on a NASCAR track.  Now put some Ice and Snow on it.   Fun times I tell you fun times.

[aviatoreb]

Oh well there goes another potentially interesting thread

[aviatoreb]

41 minutes ago, Hyett6420 said:

Why does politics have to come into this discussion?  Its totally irrelevant.  A guy was tasked with seeing whether circular runways would be better than the current method, end of discussion.  Whether it was a waste of money is actually not important for if we don't investigate we will never lesrn and improve.  

Do i personally think it is a silly idea, yes i do, but someone still somewhere has to come up with ideas.  

Hyett, I agree.

Honestly, any of you, I do not care what any of your political leanings, opinions or ideas are, even if they agree with min, and also not if they disagree with mine. I do not come here for that.   Its a sign of the times that every topic has to turn into politics.  How's the weather? I'm glad you asked, let's talk about politics.  How's the engine monitor on your TSIO520 working out for you?  I'm glad you asked, let me tell you about who I voted for and what my opinion is on your religion.  I come to talk airplane stuff mostly, and circular runways was a very cool concept to talk about, and it might be viable, it might not, but anyway, out of the box engineering ideas are a fantastic fun.  Oh well, see you all maybe on another thread.

Edited March 19, 2017 by aviatoreb

[N201MKTurbo]

So think of the takeoff planning.

First decision, Are we taking off clockwise or counterclockwise today?

let's see I need to rotate at 240 degrees to be into the wind. It takes 2000 feet to accelerate to rotation speed. The runway is 5000 feet in diameter so it is 15707 feet in conference so (2000 X 360) / 15707 = 45.8 degrees. 240 + 45.8 = 285.8 degrees (assuming counterclockwise). I would have to taxi to 285 degrees to start my takeoff roll.

Can you imagine the takeoff roll in a strong wind with continuously changing crosswinds? YaHoo! 

[N201MKTurbo]

Also think about the crazy LASHO rules on a circular runway.

Just think about capacity. How would you have parallel runways? I can't think about a reasonable way to have simultaneous operations.

[Seth]

Believe it or not, this is not the first Governemnt study or this technique:

During WWII the US Governemnt experimented with a similar runway idea for areas to build a runway where there was not a long enough strip available. 

I will see if I can find more information.

I've always been intrigued by this idea.

-Seth

[Aviationinfo]

I cannot imagine for the life of me how you'd set up a stabilized approach in a heavy for that runway, and then roll it into a bank to land.   It seems pretty unlikely in a crosswind.    

Same thing for the takeoff.  How do you start a takeoff roll on a contaminated circular runway such that you lift off --in a bank-- directly into the wind?  

And how would this runway be used to accept simultaneous takeoffs and landings?

Its a neat concept but it seems like it would be nearly impossible to work out the logistics.   If we were all flying Supercubs in Alaska, maybe...