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SomebodyInTLS
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Re: BBC: Will Circular Runways Ever Take Off?

Sat Mar 18, 2017 11:16 am

Aesma wrote:
BerenErchamion wrote:
dtw2hyd wrote:
I am just complaining about the noise generated by empty vessels. Even Casey Niestat would have showed more technical details than this guy in the video.


How dense do you have to be to not understand that a three-minute video produced for mass consumption in no way reflects the full expanse of the actual technical report?


I think the problem is right there. If you want to do a serious study on something very unusual like this, then it has to be directed at knowledgeable people. Mass consumption should not be part of the plan.


In fact this project took place in 2014 with the final updated report released in 2015.

Blame the BBC for suddenly exposing it to the masses yesterday.

(Although I, for one, am glad to have learned of it...)
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
buzzard302
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Re: BBC: Will Circular Runways Ever Take Off?

Sat Mar 18, 2017 11:55 am

Looks like an engineering "publicity stunt" to me. Perhaps to get his name out as an innovator. The slope of the runway adds additional dynamic to the control and stability of an aircraft. Just think of force vectors on an inclined plane. Is control going to be predictable in wet or icy conditions?
 
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Faro
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Re: BBC: Will Circular Runways Ever Take Off?

Sat Mar 18, 2017 2:29 pm

I think the acid test will be extreme crosswinds...regulatory authorities will be very strict with that...otherwise you need land...and lots of it...


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SomebodyInTLS
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Re: BBC: Will Circular Runways Ever Take Off?

Sat Mar 18, 2017 2:46 pm

Faro wrote:
I think the acid test will be extreme crosswinds...regulatory authorities will be very strict with that...otherwise you need land...and lots of it...


This design is *better* in extreme crosswinds than current airports. It uses *less land* than current airports. It's all in the documentation.

This feels like a bad dream where I'm back in uni defending my thesis over and over again... :lol:
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
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Faro
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Re: BBC: Will Circular Runways Ever Take Off?

Sat Mar 18, 2017 4:05 pm

SomebodyInTLS wrote:
Faro wrote:
I think the acid test will be extreme crosswinds...regulatory authorities will be very strict with that...otherwise you need land...and lots of it...


This design is *better* in extreme crosswinds than current airports. It uses *less land* than current airports. It's all in the documentation.

This feels like a bad dream where I'm back in uni defending my thesis over and over again... :lol:



I can't imagine reliving something like that...but if your thesis has gotten to the point where people are putting good money into researching it, one can only say...Bravo! Hats off to you!!

To clarify, by extreme crosswinds, I meant the gustiness associated with that type situation...gusts which can be random in direction and not always follow the prevailing wind direction...delicate managing those with a gently turning runway...

Also, if one lands in a slight turn, wouldn't we have to slightly increase airspeed to make allowance for the G load?...how does that reconcile with using less thrust on landing?...


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Barbro
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Re: BBC: Will Circular Runways Ever Take Off?

Sat Mar 18, 2017 5:25 pm

ATC is no problem, with modern tech everything can be done. There are other factors, though...
Airport expansion: building is basically limited to inside the circle.
Snow and ice removal: if the sideways slope is too steep, this becomes really tricky fast.
About wind: is that really such a big consideration? So many times have I observed pilots being more conserned about keeping schedules than landing/taking off in head- or crosswinds. There are circumstances, when the wind gets so hard that it actually restricts airport capacity, but not too many days a year at any given airport, I think..
The airflow patterns/turbulence created by having a 'stadium' of 3,5km diameter and having wind blow over it. Was this in the report?
 
dtw2hyd
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Re: BBC: Will Circular Runways Ever Take Off?

Sat Mar 18, 2017 5:56 pm

On a race track car starts and stops within the track. It doesn't enter/exit banked circle at 140-180kts
Track is at least 4-5 times wider than the car. Relatively this circular runway should be 4-5 times on current Code F.
 
Utah744
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Re: BBC: Will Circular Runways Ever Take Off?

Sat Mar 18, 2017 6:37 pm

Adipocere wrote:
I think the training requirements for such a circular runway will be significantly different and since not all airports will convert over, won't any such move cause an (unacceptable?) uptick in accidents and incidents until the pilot community's learning curve meets the level of competence and experience with straight line runways?

Figuratively and literally learning curve.
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SomebodyInTLS
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Re: BBC: Will Circular Runways Ever Take Off?

Sun Mar 19, 2017 1:42 pm

Faro wrote:
SomebodyInTLS wrote:
This feels like a bad dream where I'm back in uni defending my thesis over and over again... :lol:


I can't imagine reliving something like that...but if your thesis has gotten to the point where people are putting good money into researching it, one can only say...Bravo! Hats off to you!!


Just to be clear - I have nothing to do with this project... just that I felt compelled to rebuff the dismissive responses on here when the things they mention have actually been thought about.

To clarify, by extreme crosswinds, I meant the gustiness associated with that type situation...gusts which can be random in direction and not always follow the prevailing wind direction...delicate managing those with a gently turning runway...

Also, if one lands in a slight turn, wouldn't we have to slightly increase airspeed to make allowance for the G load?...how does that reconcile with using less thrust on landing?...


To be honest, I'm not qualified to quantify these details - but if it's a mild curve (which I think it is) then it can't be any harder than crabbing during heavy crosswind. That seems like a more extreme aircraft situation to me.
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
dtw2hyd
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Re: BBC: Will Circular Runways Ever Take Off?

Sun Mar 19, 2017 3:35 pm

Barbro wrote:
The airflow patterns/turbulence created by having a 'stadium' of 3,5km diameter and having wind blow over it. Was this in the report?


It also needs a sophisticated active drinage system to keep the 3.5km dia bowl dry all the time. Otherwise they need an evacuation system because both terminal and underground access roads are first to be flooded.
 
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SomebodyInTLS
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Re: BBC: Will Circular Runways Ever Take Off?

Sun Mar 19, 2017 5:44 pm

dtw2hyd wrote:
Barbro wrote:
The airflow patterns/turbulence created by having a 'stadium' of 3,5km diameter and having wind blow over it. Was this in the report?


It also needs a sophisticated active drinage system to keep the 3.5km dia bowl dry all the time. Otherwise they need an evacuation system because both terminal and underground access roads are first to be flooded.


People are still letting their imagination run riot... It looks nothing like a "bowl"... more like a modern flat dinner plate. The runway is a very thin lip running around the edge.

Same thing with the question of airport expansion... it doesn't look at all space limited - there is a central terminal and four satellite terminals in the proposed format, and the study looked at using car-parks etc. to form part of the runway bank. In the event you want to add more passenger handling, car-parks, hotels etc. then that can simply be set outside the circle. Road and rail access is already expected to go under the runway, so where's the problem?
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
KFLLCFII
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Re: BBC: Will Circular Runways Ever Take Off?

Mon Mar 20, 2017 11:27 am

Not sure if this was mentioned, but the entire touchdown zone (with regard to an approach path) would essentially be the single point on a circle at which a tangential line touches it...There would be almost no tolerance whatsoever for overshooting or undershooting the touchdown aiming point by even a small margin.
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Re: BBC: Will Circular Runways Ever Take Off?

Mon Mar 20, 2017 11:50 am

SomebodyInTLS wrote:
People are still letting their imagination run riot... It looks nothing like a "bowl"... more like a modern flat dinner plate. The runway is a very thin lip running around the edge.

Same thing with the question of airport expansion... it doesn't look at all space limited - there is a central terminal and four satellite terminals in the proposed format, and the study looked at using car-parks etc. to form part of the runway bank. In the event you want to add more passenger handling, car-parks, hotels etc. then that can simply be set outside the circle. Road and rail access is already expected to go under the runway, so where's the problem?


Well it's not as steep as a stadium, off course, or a bowl. But with the inclines discussed here, there is a more pronounced "lip" right where it matters, ie next to the runway. Does it affect the airflow greatly, I don't know but I would check it. Even forest edges have to be well off of runway-edges in already excisting airports.

Carparks etc are not the problem, but terminals (where aircraft would actually have to park next to a building). A diameter of 3,5 km, minus a taxiway system, and your're already at under 3 km. Just have a look at LHR for example. Or any other bigger airport. All have needs for terminal capacity that would fill this area easily.
 
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Re: BBC: Will Circular Runways Ever Take Off?

Mon Mar 20, 2017 6:41 pm

KFLLCFII wrote:
Not sure if this was mentioned, but the entire touchdown zone (with regard to an approach path) would essentially be the single point on a circle at which a tangential line touches it...There would be almost no tolerance whatsoever for overshooting or undershooting the touchdown aiming point by even a small margin.

You are imagining a much smaller circle than the project envisions. The approach is a normal 3° glideslope, and when you are over the runway, you enter a specific bank angle. The turn reduces lift slightly, and the aircraft descends to the runway. If you are too high or low, it's an unstable approach, and you go around. In terms of the approach, it sounds like the exact same expectation you would have of any commercial pilot at any normal airfield. It's not LCY.
 
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Re: BBC: Will Circular Runways Ever Take Off?

Mon Mar 20, 2017 9:14 pm

It is very interesting to see people looking at this idea and then dismissing it by applying all their knowledge and procedures that were developed for straight runways with limited lengths.
Think outside the box! All your conventional stuff goes out the window! Why do you need a TD point? Not necessary because you won't run out of runway. Why v1? There is no limit to the runway. Heck you don't need a precision approach to land with precision mins. No vertical guidance necessary you just keep circling till you hit the deck. You don't even need a go-around in a classical sense because the landing is the go around. You aren't perfectly lined up, well correct and land. You have another problem, just stretch the landing. The runway is infinite! You can't get any safer then that, you can basically throw out the majority of preflight calculations and landing restrictions because it is all based on a limited runway and limited time spent on the runway. Sure it's not all that rosy, but don't argue with the exhaust system's or gearbox requirements for an electric car.
 
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Re: BBC: Will Circular Runways Ever Take Off?

Mon Mar 20, 2017 10:53 pm

It's actually a wonderful idea.

Let's spin the circular runway like a roulette wheel. And off you go!


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Re: BBC: Will Circular Runways Ever Take Off?

Tue Mar 21, 2017 2:31 am

Bugs,
Yes you could look at it as unlimited runway length, but the original concept says it is equivalent to 6 runways. By landing full circle, you take that capacity away.
Is just me, or is flying not as much fun anymore?
 
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Re: BBC: Will Circular Runways Ever Take Off?

Tue Mar 21, 2017 5:44 am

Yes, I meant that by "its not all rosy". The capacity issues are something that doesn't immediately jump at me for a similar solution. But again we are thinking in old terms and straight approaches - maybe there's a whole different world out there. And then it's not like that professional pilots have a hard time hitting the TDZ quite regularly. So going over your landing distance doesn't mean big emergency screwed up landing separation for the whole airport. Even if there is another plane on that runway for the very worst case - look how "wide" it is, 'nough room for two.
I just find it fascinating that this concept basically gives a fixed wing the same landing "attitude" as a helicopter pilot with ample power reserves has - just approach and take your time, touch down when everything is perfect. No rush, no timer counting down, no one chance or go around. And IMC approaches man - no MAP, no TDZ. Just take it slow, reduce your descent rate to 20ft/min at DA of 200ft or less and wait till you really see the lights. How difficult is holding a DME arc? Sure that fucks the separation and capacity unless you have all the planes staggered on a downward spiral with less than standard separation. And then again - glider pilots know how safe it is to fly in a circle with several other planes at touching distance. Ok, now I'm really getting into fantasyland ;)
Maybe it's more something for smaller planes and airports. But think of test flights/training. Just as safe as IMC landing can be as you can drag it out forever, so is taking off. As long as you stay over the runway - and you can do that as long as you have fuel - you can land right below on your runway. Imagine on a quiet day "53N I'd like to fly a few circuits till my engine quits, I have 5mins of fuel on board". Or flight training - wanna do some touch and gos? How about 10 in 10 minutes - in a fixed wing! Okok, I stop.
 
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Re: BBC: Will Circular Runways Ever Take Off?

Tue Mar 21, 2017 11:29 am

Barbro wrote:
Carparks etc are not the problem, but terminals (where aircraft would actually have to park next to a building). A diameter of 3,5 km, minus a taxiway system, and your're already at under 3 km. Just have a look at LHR for example. Or any other bigger airport. All have needs for terminal capacity that would fill this area easily.


The proposal looks to have plenty of stands and taxiway, with good access to everything. The only possible flaw (purely in terms of the illustration) is that the terminal space looks small for the number of stands it has. But there would certainly be underground connections between all those building, so presumably we're just seeing the tips of the iceberg and the passenger handling, baggage systems, security checks etc. etc. could all be in the interconnecting lower levels...
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
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Re: BBC: Will Circular Runways Ever Take Off?

Tue Mar 21, 2017 11:33 am

exFWAOONW wrote:
Bugs,
Yes you could look at it as unlimited runway length, but the original concept says it is equivalent to 6 runways. By landing full circle, you take that capacity away.


But since you're coming in at typical landing speeds then you're not going to somehow "catch up" with the other guys if you have some kind of emergency. The ones landing in front of you will already have turned onto a taxiway while the ones about to takeoff will just be told to hold short..
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
flipdewaf
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Re: BBC: Will Circular Runways Ever Take Off?

Tue Mar 21, 2017 4:10 pm

SomebodyInTLS wrote:
exFWAOONW wrote:
Bugs,
Yes you could look at it as unlimited runway length, but the original concept says it is equivalent to 6 runways. By landing full circle, you take that capacity away.


But since you're coming in at typical landing speeds then you're not going to somehow "catch up" with the other guys if you have some kind of emergency. The ones landing in front of you will already have turned onto a taxiway while the ones about to takeoff will just be told to hold short..

What would the Natural speed be at 80m difference in radius? aircraft that are going different speeds and maybe might collide would automatically be at different heights/widths. The 80m max as we use now could indicate a maximum closing speed..... I want to try one in flight simulator.

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Mir
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Re: BBC: Will Circular Runways Ever Take Off?

Tue Mar 21, 2017 4:21 pm

SomebodyInTLS wrote:
This design is *better* in extreme crosswinds than current airports. It uses *less land* than current airports.


It isn't, and it doesn't.

Take ATL as an example. Even if you take away the 5th runway, you can still get more capacity from the four remaining ones than you could get from a single circular runway, and you can do it in all wind conditions (whereas the circular runway would have the capacity of a single runway in strong winds). And the area bounded by those four runways is smaller than the area bounded by the proposed circular runway.
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Mir
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Re: BBC: Will Circular Runways Ever Take Off?

Tue Mar 21, 2017 4:26 pm

Faro wrote:
To clarify, by extreme crosswinds, I meant the gustiness associated with that type situation...gusts which can be random in direction and not always follow the prevailing wind direction...delicate managing those with a gently turning runway...


And let's complicate things by adding in a mechanical turbulence generator (the lip of the banking) right next to the runway so that its effects are felt just as the aircraft is trying to touch down, and let's complicate them even further by reducing the tolerances for bank angle in response to that turbulent flow because the banking of the runway gives less room before striking a wingtip or engine on the ground.

That seems like a good idea.
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flipdewaf
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Re: BBC: Will Circular Runways Ever Take Off?

Tue Mar 21, 2017 7:30 pm

Faro wrote:
To clarify, by extreme crosswinds, I meant the gustiness associated with that type situation...gusts which can be random in direction and not always follow the prevailing wind direction...delicate managing those with a gently turning runway...
not sure why this is more complex than a straight runway?

Mir wrote:
And let's complicate things by adding in a mechanical turbulence generator (the lip of the banking) right next to the runway so that its effects are felt just as the aircraft is trying to touch down
I agree, there could be a nasty bit of turbulence there, I guess glider pilots know about those type of winds.
Mir wrote:
let's complicate them even further by reducing the tolerances for bank angle in response to that turbulent flow because the banking of the runway gives less room before striking a wingtip or engine on the ground.
again, not sure why its seen as so difficult. I calculated the required rate of change of bank across the runway and I'm pretty sure the reduction in clearances would be in the order of inches a cross a wingspan.

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dtw2hyd
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Re: BBC: Will Circular Runways Ever Take Off?

Tue Mar 21, 2017 11:35 pm

flipdewaf wrote:
Faro wrote:
To clarify, by extreme crosswinds, I meant the gustiness associated with that type situation...gusts which can be random in direction and not always follow the prevailing wind direction...delicate managing those with a gently turning runway...
not sure why this is more complex than a straight runway?

Mir wrote:
And let's complicate things by adding in a mechanical turbulence generator (the lip of the banking) right next to the runway so that its effects are felt just as the aircraft is trying to touch down
I agree, there could be a nasty bit of turbulence there, I guess glider pilots know about those type of winds.
Mir wrote:
let's complicate them even further by reducing the tolerances for bank angle in response to that turbulent flow because the banking of the runway gives less room before striking a wingtip or engine on the ground.
again, not sure why its seen as so difficult. I calculated the required rate of change of bank across the runway and I'm pretty sure the reduction in clearances would be in the order of inches a cross a wingspan.

Fred


Just to be clear, we are talking about earth surface here, correct, not space, not in a dome anything like that. I ask this dumb question because every one seems to talking about wind blowing in straight lines, no wind shear, no micro bursts, no down draft.

If you ever owned a Logitech G25/G27 racing wheel, it had a problem going off center by few degrees, making it difficult to use. Now imagine hours of level flight, suddenly for few seconds you have to ignore what horizon says and your body feels you have to achieve a perfect touch down. No scope for long landing.
 
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Re: BBC: Will Circular Runways Ever Take Off?

Wed Mar 22, 2017 8:37 am

Smith, C., "Flight Operations on a Circular Runway," SAE Technical Paper 660283:

Inherent advantages of an infinitely long runway, optimum technical location at the center of the circle, and safety enhancement by increased directional stability during aircraft ground roll generated interest in the circular runway concept. The Bureau of Naval Weapons originated a project to determine, within the realm of aircraft behavior, the feasibility of flight operations from a circular runway.Utilizing an existing circular track at the General Motors Proving Ground near Mesa, Arizona, tests were conducted with a T28, an A1-E, an A4-B, and a C54. It was determined that pilots readily adapt to operations from a circular runway, that aircraft lateral and directional stability is more positive than on a flat runway, that tangential approaches are no more difficult than approaches to a straight runway, and that low visibility approaches are much simpler than to a straight runway. Flight operations from a circular runway are feasible.

Again guys: most of the technical aspects of flying that are used to criticize this turn out to be advantages. Ask why it is a problem (on a straight runway)? Then look at the circle and you simply won't have that problem. Take the increased g-force for example. Yes, it increases stall speed - a little. Why is that a problem in our world? - because your runway is normally limited and you worry about slowing especially if it's contaminated. Now look at the racetrack: Increased g-forces will increase runway friction and increase braking action. Increased speed will positively influence controllability and control - so does wing loading and so does flying a turn. All that benefits turbulence behaviour in turn. Did I mention contamination? Well how about that on a slope!
One point of the circle is that you have 35 runways available - of course you don't choose the one with turbulence before TD. Even If the runway should cause turbulence ( and it never would since building it to produce turbulence would be kinda stupid just like putting a hangar next to a straight runway's final) you don't have to land in it. It's a local thing, move along.

The other thing people worry about is the centerline. The beauty of the racetrack is that the plane will find it's centerline depending on speed automatically! It is a self regulating system of centrifugal forces and gravity. Just keep the ball centered, fly by the seat of your pants.

Think about the easy ground ops - short direct ways, no runway crossings, simple taxi, a visible runway.
 
flipdewaf
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Re: BBC: Will Circular Runways Ever Take Off?

Wed Mar 22, 2017 9:22 am

dtw2hyd wrote:
Just to be clear, we are talking about earth surface here, correct, not space, not in a dome anything like that. I ask this dumb question because every one seems to talking about wind blowing in straight lines, no wind shear, no micro bursts, no down draft.
Why is this different from a straight runway? When a conventionally controlled/configured aircraft is in a constant turn it is a very stable platform, in fact more stable than in straight and level flight.

dtw2hyd wrote:
If you ever owned a Logitech G25/G27 racing wheel, it had a problem going off center by few degrees, making it difficult to use.
so you are saying if you have a bad control system that wont stay in trim correctly then it won't work very well here? Probably find that difficult on a straight runway.
dtw2hyd wrote:
Now imagine hours of level flight, suddenly for few seconds you have to ignore what horizon says and your body feels you have to achieve a perfect touch down.

Horizon tells you what the horizon is, the aim of this is to follow a particular bank angle at a particular speed, like any pilot does for a turn, bank for a standard rate turn. What your body feels? well I'd guess that any pilot who is allowed to fly by them selves should be reasonably capable for a coordinated turn and so the difference in feeling would be <0.1g.
dtw2hyd wrote:
No scope for long landing.
Or in fact infinite scope for a long landing if such conditions arise and are required.

bugsbegone wrote:
Smith, C., "Flight Operations on a Circular Runway," SAE Technical Paper 660283:
Great information, its a shame people are so closed minded, good job those who count aren't.

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SomebodyInTLS
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Re: BBC: Will Circular Runways Ever Take Off?

Wed Mar 22, 2017 10:24 am

flipdewaf wrote:
bugsbegone wrote:
Smith, C., "Flight Operations on a Circular Runway," SAE Technical Paper 660283:
Great information, its a shame people are so closed minded, good job those who count aren't.


Yes, and guess what...? That quote from bugsbegone of the 1960s study was also in the report for this project.It's not like they didn't, you know, do research or anything.

People like to think they can form a better judgement of a concept by reading a headline than a team of aerospace engineers from a bunch of national aerospace bureaus who spend months investigating every aspect they and their national agencies can think of.
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
dtw2hyd
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Re: BBC: Will Circular Runways Ever Take Off?

Wed Mar 22, 2017 11:42 am

bugsbegone wrote:
Think about the easy ground ops - short direct ways, no runway crossings, simple taxi, a visible runway.

Think about infinite possibilities of runway excursions. Every landing will be miracle. Imagine how much EMAS would be required to cover entire circle.

flipdewaf wrote:
Why is this different from a straight runway? When a conventionally controlled/configured aircraft is in a constant turn it is a very stable platform, in fact more stable than in straight and level flight.

Probably find that difficult on a straight runway.

Or in fact infinite scope for a long landing if such conditions arise and are required.


A straight runway is "straight" and "level", few less variables pilot have to deal with.
 
Mir
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Re: BBC: Will Circular Runways Ever Take Off?

Wed Mar 22, 2017 1:18 pm

bugsbegone wrote:
One point of the circle is that you have 35 runways available - of course you don't choose the one with turbulence before TD. Even If the runway should cause turbulence ( and it never would since building it to produce turbulence would be kinda stupid just like putting a hangar next to a straight runway's final) you don't have to land in it. It's a local thing, move along.


They all have turbulence. The way the runway is built, with a lip on the outer edge due to the banking, ensures this. Wind passing over that edge will produce turbulence, there's no way around it. So you're not really going to be moving along unless you want to land somewhere else.

flipdewaf wrote:
I agree, there could be a nasty bit of turbulence there, I guess glider pilots know about those type of winds.


No more than anybody else. Sometimes you have to deal with them, but you don't want to if you can avoid it.

flipdewaf wrote:
the aim of this is to follow a particular bank angle at a particular speed, like any pilot does for a turn, bank for a standard rate turn.


It's more complicated than that - the bank angle would need to be changing throughout the landing due to both speed and wind.

It's not an insurmountable challenge - putting the aircraft on the runway is probably the most feasible thing about this, even with the additional issues it presents. But the big question is why go to all the trouble when a conventional setup is better at maintaining capacity while dealing with wind, is more space-efficient, and can be more easily expanded to meet demand? Even in the best case scenario of having three aircraft using the circular runway simultaneously you're still worse off than you could be.
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Re: BBC: Will Circular Runways Ever Take Off?

Tue Mar 28, 2017 1:25 pm

AeroTyke wrote:
How does the plane get up onto the banking to take off? One minute you're driving your plane along at a decent pace on the flat, then suddennly you're faced with a steep hill in front of you which you need to power up and swing your plane round on. Also at that kind of angle as illustrated in the video, wouldn't the plane tip sideways onto its wing tip? All the pax would be leaning to the side until it reaches a certain speed on the take off roll too.

Also how would ATC know where to put them on the loop to start their take off roll? ATC would need to have them airborne at a certain point so that when they lift off they are heading x degrees and not y degrees about to have a head on with a plane coming in to land. Add in some wind gusts either increasing or decreasing the length of the expected take off roll and ATC has a nightmare on their hands.

It's a stupid April 1st idea and will never see the light of day.


These problems you are stating are valid and at first I thought it was an April 1st joke aswell. However, when you look at the following link: http://www.endlessrunway-project.eu/documents/index.php
They made several analyses of at 100+ pages on the endless runway. Quite the efford for April Fool's?
 
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ro1960
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Re: BBC: Will Circular Runways Ever Take Off?

Sun Apr 02, 2017 6:58 am

I don't know if it's an April Fool's joke but seriously, can an aircraft land or take off on a curved trajectory? Seems very unlikely.
 
MalevTU134
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Re: BBC: Will Circular Runways Ever Take Off?

Sun Apr 02, 2017 9:13 am

ro1960 wrote:
I don't know if it's an April Fool's joke but seriously, can an aircraft land or take off on a curved trajectory? Seems very unlikely.

Have a look at this runway:

https://www.google.se/search?q=avedore+ ... Hr_av7h6OM:
Or this, of course:

https://youtu.be/mEN_mwn_NaM
 
smokeybandit
Posts: 626
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Re: BBC: Will Circular Runways Ever Take Off?

Sun Apr 02, 2017 11:24 am

How would you abort a takeoff on such a runway? Especially if you've got other aircraft on the runway.
 
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SomebodyInTLS
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Re: BBC: Will Circular Runways Ever Take Off?

Sun Apr 02, 2017 12:28 pm

smokeybandit wrote:
How would you abort a takeoff on such a runway? Especially if you've got other aircraft on the runway.


Very easily. Much easier than on a typical runway. Just read any of the report.

Seriously, the only thing I can think of that is actually going to be "dangerous" on the circular runway but not on the straight one (which has an end you have to either stop or fly before, don't forget) is if somehow your aircraft gets stuck in "straight ahead". But that's not going to make reaching your destination very likely, is it...
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
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ro1960
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Re: BBC: Will Circular Runways Ever Take Off?

Sun Apr 02, 2017 2:01 pm

MalevTU134 wrote:
ro1960 wrote:
I don't know if it's an April Fool's joke but seriously, can an aircraft land or take off on a curved trajectory? Seems very unlikely.

Have a look at this runway:

https://www.google.se/search?q=avedore+ ... Hr_av7h6OM:
Or this, of course:

https://youtu.be/mEN_mwn_NaM



Mmmm... yeah but no. This is nothing like a circular runway with a sharp constant curve as described in the project. Just a slight curve linking to straight segments.

Other claimed arguments like "improve the flying experience for both passengers and pilots, making for smoother departures and arrivals, save energy and space" are just airy-fairy to me.
 
jomur
Posts: 86
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Re: BBC: Will Circular Runways Ever Take Off?

Fri Apr 21, 2017 9:23 am

Today on the BBC the engineer who proposed this has been answering some of the concerns raised if any one is still interested.
http://www.bbc.co.uk/news/magazine-39643292
 
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SomebodyInTLS
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Re: BBC: Will Circular Runways Ever Take Off?

Fri Apr 21, 2017 10:12 am

I was just about to post the same article. :)
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
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ro1960
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Re: BBC: Will Circular Runways Ever Take Off?

Fri Apr 21, 2017 10:31 am

jomur wrote:
Today on the BBC the engineer who proposed this has been answering some of the concerns raised if any one is still interested.
http://www.bbc.co.uk/news/magazine-39643292


Thanks for posting.

I must say that I am not an ounce more convinced after reading the replies from Mr. Hesselink. Well, the only thing I am convinced of is that it would take a lot of trial and errors, modifications of current procedures, costly airport design and construction for very little benefits. All the advantages put forward (making airports greener and less noisy, no crosswind issue, multiple simultaneous landings and take-offs, avoiding tricky landings, positive social and environment impact, less fuel burn) don't IMHO hold water.
 
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SomebodyInTLS
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Re: BBC: Will Circular Runways Ever Take Off?

Fri Apr 21, 2017 4:17 pm

ro1960 wrote:
jomur wrote:
Today on the BBC the engineer who proposed this has been answering some of the concerns raised if any one is still interested.
http://www.bbc.co.uk/news/magazine-39643292


Thanks for posting.

I must say that I am not an ounce more convinced after reading the replies from Mr. Hesselink. Well, the only thing I am convinced of is that it would take a lot of trial and errors, modifications of current procedures, costly airport design and construction for very little benefits. All the advantages put forward (making airports greener and less noisy, no crosswind issue, multiple simultaneous landings and take-offs, avoiding tricky landings, positive social and environment impact, less fuel burn) don't IMHO hold water.


Funny that I'm just reading about a successful trial of precision curved approaches carried out by Airbus, LH and Swiss using current equipment and airports (on commercial flights, apparently) in Germany and Switzerland as part of the SESAR project (Single European Sky Air Traffic Management Research). Seems the ATM world have already discounted most arguments about the "difficulties" of this kind of flying...
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
dtw2hyd
Posts: 4985
Joined: Wed Jan 09, 2013 12:11 pm

Re: BBC: Will Circular Runways Ever Take Off?

Fri Apr 21, 2017 4:34 pm

One of the Indian regional language newspapers published a plane image(nothing to do with circular runways), but exactly looks like an attempt to land on a circular runway.

Smiley face and thumbs up makes it perfect.

Image
 
flipdewaf
Posts: 1949
Joined: Thu Jul 20, 2006 6:28 am

Re: BBC: Will Circular Runways Ever Take Off?

Fri Apr 21, 2017 8:03 pm

ro1960 wrote:
All the advantages put forward (making airports greener and less noisy, no crosswind issue, multiple simultaneous landings and take-offs, avoiding tricky landings, positive social and environment impact, less fuel burn) don't IMHO hold water.
can you explain why you believe this? I find it quite conceivable in principle but the infrastructure change seems a big hurdle.

Fred
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