It would be good for cases of brake failure - just keep going round in circles until the plane eventually slows down and stops. Also, there is no risk of runway overruns on take off or landings. However, landing sideways in some kind of shallow turn looks pretty difficult to me. It´s hard enough to keep a plane going straight on the runway using the pedals but if you also had to turn continuously it would be hard work to stay in the middle of the runway and avoid going off the sides.

It would have to be a really really big circle and I think it could be a problem that the outside wheels would touch down first. As for winds, it would be a bit unpredictable because the wind direction at takeoff would depend on your position when you reached takeoff speed, which you wouldn´t know for sure. For landing it would be great because you could always land into the wind. It seems like a crazy idea, but actually the bigger the circle the more it makes sense.

aerolimani wrote:

There is a strong tendency I've noticed for a.netters to analyze everything like an engineer; in a very linear fashion. Some money does need to be spent exploring wild possibilities. Until you go down a road, you don't know where it leads. The world needs people who think and work like scientists and artists. Most world-altering breakthroughs happen because of lateral thinking. Even if an idea like this turns out to be unfeasible, that doesn't mean there aren't some important and useful discoveries made.

So… instead of being harsh and dismissive, spending time and energy telling us all why it would never work, why not spend some time wondering what useful discoveries might come out of this.

That is because drama is taking precendence over convincing data. Do you think someone interested in a space launch will ignore a failure because someone cute hosting the webcast? Apparently someone thinks so.

It helps to imagine taking a box of 4 straight runways, with length of 8200 feet/2500 meters per side/runway.

What you're doing is taking that box and gently curving and banking it so it's one big runway of circumference 9500m.

The curving/banking is not that severe. In exchange you get some intriguing advantages.

Tugger wrote:

Capacity is the real problem to me. You are stuck with "four runway blocks" when building.

I still haven't read the report, but I would imagine you could build a second circle (with a sufficient gap) to increase capacity. You obviously can't have aircraft landing / taking off across the neighbouring runway, so I imagine you'd end up with an equivalent capacity of about 6 runways instead of the 4 from one circle.

peterinlisbon wrote:

It would be good for cases of brake failure - just keep going round in circles until the plane eventually slows down and stops. Also, there is no risk of runway overruns on take off or landings.

Great! Someone thinking about the interesting possibilities instead of just shooting it down after two seconds of thinking "it's different, therefore it's bad" (which seems to be in vogue these days...)

However, landing sideways in some kind of shallow turn looks pretty difficult to me. It´s hard enough to keep a plane going straight on the runway using the pedals but if you also had to turn continuously it would be hard work to stay in the middle of the runway and avoid going off the sides.

That's why I was thinking this would be perfect for automation...

It would have to be a really really big circle

The pictures certainly look that way. People are reacting like you'll be on a theme park ride, but it's probably barely noticeable from the passenger point of view.

and I think it could be a problem that the outside wheels would touch down first. As for winds, it would be a bit unpredictable because the wind direction at takeoff would depend on your position when you reached takeoff speed, which you wouldn´t know for sure.

Again, automation would probably have no problem with all of that since the entire procedure would follow an optimised track taking wind etc. into consideration. For manual flying you would probably have to follow a very precise tunnel-in-the-sky, and keep strictly to the planned airspeed at all times...

For landing it would be great because you could always land into the wind. It seems like a crazy idea, but actually the bigger the circle the more it makes sense.[/quote]

Yeah, it's certainly interesting.

dtw2hyd wrote:

aerolimani wrote:

There is a strong tendency I've noticed for a.netters to analyze everything like an engineer; in a very linear fashion. Some money does need to be spent exploring wild possibilities. Until you go down a road, you don't know where it leads. The world needs people who think and work like scientists and artists. Most world-altering breakthroughs happen because of lateral thinking. Even if an idea like this turns out to be unfeasible, that doesn't mean there aren't some important and useful discoveries made.

So… instead of being harsh and dismissive, spending time and energy telling us all why it would never work, why not spend some time wondering what useful discoveries might come out of this.

That is because drama is taking precendence over convincing data. Do you think someone interested in a space launch will ignore a failure because someone cute hosting the webcast? Apparently someone thinks so.

And some people need to understand what an academic study is. It's different from an assessment. Not every study has to be commissioned with the mindset of arriving at a directly and immediately applicable outcome. Research for the sake of research has its place. This study wasn't commissioned because someone said "All airports must be changed to a circular configuration, so tell us how to make it happen." It's a study of what-if, and the pros and cons. Maybe nothing useful will come of it. Granted, there's some ridiculous studies out there, and thus we have the Ig Nobel Prizes. But, maybe there are some useful lessons to draw from the study.

So, how about this. Instead of basing an entire discussion off a dumbed-down BBC magazine video, perhaps it would be wiser for us all to read the study first. http://www.endlessrunway-project.eu/

It appears that every landing would be a side slip or cross control landing, as if into a crosswind. Definitely more challenging.

Actively flying commercial airplanes for the last 33 years; the impracticality of this ridiculousness is so overwhelming as to make the subject nonsensical.

I think it's an amazing bit of creative thinking. Do I think it will happen? No - for all the reasons people above have listed and more. Very cool idea, however.

AirFiero wrote:

It appears that every landing would be a side slip or cross control landing, as if into a crosswind. Definitely more challenging.

Actually - even just from the executive summary of the report - that's not true at all. In fact wind conditions are one of the main advantages of this system!

Like I said before; this is not a theme park ride. The total circumference of the track is 10km! Far from being in a side wind "most of the time", the whole point in high wind conditions is to taxi to a point where the whole takeoff run is into headwind!

Just glancing through the final report shows that all the opinionated one-liners on here are completely ignorant of what this concept actually means.

Piedmont767LGW wrote:

Actively flying commercial airplanes for the last 33 years; the impracticality of this ridiculousness is so overwhelming as to make the subject nonsensical.

Case in point...

aerolimani wrote:

And some people need to understand what an academic study is. It's different from an assessment. Not every study has to be commissioned with the mindset of arriving at a directly and immediately applicable outcome. Research for the sake of research has its place. This study wasn't commissioned because someone said "All airports must be changed to a circular configuration, so tell us how to make it happen." It's a study of what-if, and the pros and cons. Maybe nothing useful will come of it. Granted, there's some ridiculous studies out there, and thus we have the Ig Nobel Prizes. But, maybe there are some useful lessons to draw from the study.

So, how about this. Instead of basing an entire discussion off a dumbed-down BBC magazine video, perhaps it would be wiser for us all to read the study first. http://www.endlessrunway-project.eu/

Idea looks good in slow motion animation, speed it up to 180 kts, every take off and landing is second chance on life for crew and passengers. I would be happy to buy a house close to SpaceX's Landing Zone 1, but not anywhere near an endless runway airport.

All they need to do is to create this airport in a SIM train one person to land and take off in the SIM. Now teenagers are working hard to prove this theory on their FSX.

I have only read the articles superficially, but on a Danish website a commentator noted that the inventor apparently believes that aircraft will be able to fly at slower speeds during a circular landing (as opposed to straight-in approaches of today). That point alone shows how little the person behind this concept knows about aviation.
Another hole I see in the concept is the idea that it would create less noise. Obviously an aircraft that is turning will generate more noise, and would create significantly more noise than a CDA approach would.

I think the proposal so far sounds completely bonkers, but I could see a future potential. Autonomous aircraft could fly circular approaches and departures where it essentially just circles overhead the airport/runway while climbing/descending, and basing the approach/departure on a single VOR/DME located in the middle of the circle. But with current technology? Never. And I still have my doubts about the claims that it will reduce noise. IMHO, the new method of having final approaches that aren't a single constant course (I forgot the what it is called) sounds far more promising.

SomebodyInTLS wrote:

Like I said before; this is not a theme park ride. The total circumference of the track is 10km! Far from being in a side wind "most of the time", the whole point in high wind conditions is to taxi to a point where the whole takeoff run is into headwind!

So you're saying in high winds a large circular runway has the advantage because the whole take off or landing will be with a general headwind? But, this also reduces your infinite runway to a single runway. I think a busy airport would prefer multiple runways with strong crosswinds.

dragon6172 wrote:

So you're saying in high winds a large circular runway has the advantage because the whole take off or landing will be with a general headwind? But, this also reduces your infinite runway to a single runway. I think a busy airport would prefer multiple runways with strong crosswinds.

That brings out another issue, how would you close a section of the runway for maintenance.

Yes this isn't a finished and practical proposal as it stands but as was mentioned above it is very important that this "sort" of thing is at least studied and given some actual and practical thought going in to it. If Eddison thought like a lot of people here then we'd be wondering around lit by really bright and efficient candles.

Surely the fact that it has a continuously varying slope makes control on the ground relatively benign. Control inputs aren't required to keep you turning for exactly the same reason that a nascar circuit is banked to make all the terrorists go to sleep through boredom to make the resolved centripetal and gravitational forces resolve to the angle of bank.

As for ATC, well, humans invented it to work with straight runways, invent a different way of making it work with circular runways, we decided to make it how it is so we can un-decide it.

I think we deride these things too early when there could be useful insights from doing the tests/thought experiments. What if this technology was able to allow high speed exits from runways at much greater speeds and increase airport capacities. as was mentioned above this seems potentially a totally fine solution for fully autonomous air vehicles.
It's not the final solution for an airport but investigating potential solutions to problems that exist.

Fred

Dardania wrote:

LupineChemist wrote:

If the bank angle of the runway were matched to the radius of the curve, maybe there would be no appreciable feeling of centripetal force in use...

This would be the same idea as high speed car test tracks e.g. Nardo ( https://en.wikipedia.org/wiki/Nard%C3%B2_Ring ) where each lane (bank angle) has a natural speed where no steering is required to drive "straight".

The planes would be accellerating though so would need to prescribe a gentle spiral on the bowl to get this effect

Takeoff/approach paths
ILS
ATC
weather

probably at least 5 more!!!

Too many factors and issues to be considered and answered for this to work.

dtw2hyd wrote:

dragon6172 wrote:

So you're saying in high winds a large circular runway has the advantage because the whole take off or landing will be with a general headwind? But, this also reduces your infinite runway to a single runway. I think a busy airport would prefer multiple runways with strong crosswinds.

That brings out another issue, how would you close a section of the runway for maintenance.

I see people still aren't bothering to look at the report...

It's not an infinite runway in the sense that you run around and around it and then take off... you just use the most convenient section based on route and, if necessary, wind direction,

In high winds, you still have TWO sections of the track parallel to the wind direction, whatever that is. That is actually an advantage over any existing airport - where even with many different runway headings these will rarely be optimal wrt. wind direction and transition from use of one runway to another will take time.

Closure of a section of runway will therefore limit it in the same way that high winds will... a reduction in capacity, but no more than that.

bmacleod wrote:

Takeoff/approach paths
ILS
ATC
weather

probably at least 5 more!!!

Too many factors and issues to be considered and answered for this to work.

Again... how about actually reading the report (even just the final summary) where these factors *ARE* considered and answered.

What do you do during your approach if you come in a little bit high?

ILS by the way might not be necessary if you use modern satelite navigations with a precision of approx. 1m

SomebodyInTLS wrote:

I see people still aren't bothering to look at the report...

Exactly. Depressing how many people are quick to criticise the authors as knowing nothing about aviation, yet are unable to click a link and read a document. The assessment one covers most of the concerns. It would be great to have an intelligent conversation about whether those concerns have been met. And yes, dtw2hyd, plenty of sim time was put in.
http://www.endlessrunway-project.eu/dow ... runway.pdf
Sadly, empty vessels do make the most noise.

BaconButty wrote:

SomebodyInTLS wrote:

I see people still aren't bothering to look at the report...

Exactly. Depressing how many people are quick to criticise the authors as knowing nothing about aviation, yet are unable to click a link and read a document. The assessment one covers most of the concerns. It would be great to have an intelligent conversation about whether those concerns have been met. And yes, dtw2hyd, plenty of sim time was put in.
http://www.endlessrunway-project.eu/dow ... runway.pdf
Sadly, empty vessels do make the most noise.

There is ton of talk about modelling. I have seen a reference to xplane, but nothing about simulation. Is it available for download, or a video of a human on sim?

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.

dtw2hyd wrote:

BaconButty wrote:

SomebodyInTLS wrote:

I see people still aren't bothering to look at the report...

Exactly. Depressing how many people are quick to criticise the authors as knowing nothing about aviation, yet are unable to click a link and read a document. The assessment one covers most of the concerns. It would be great to have an intelligent conversation about whether those concerns have been met. And yes, dtw2hyd, plenty of sim time was put in.
http://www.endlessrunway-project.eu/dow ... runway.pdf
Sadly, empty vessels do make the most noise.

There is ton of talk about modelling. I have seen a reference to xplane, but nothing about simulation. Is it available for download, or a video of a human on sim?

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.

"To evaluate operations on the Endless Runway, the most constraining aircraft that is currently in operation has been selected for trial: the Boeing 747, where the outer engine will have the smallest clearance with the ground. The evaluation will be performed with a 6 Degrees of Freedom (DOF) simulation tool. There are several 6DOF simulators available (commercial and free) and all aeronautical research centers developed their own proprietary systems over the years. Flight Gear was selected for use in the project.

The objective of the simulations is to take an existing passenger aircraft and to operate it on an Endless Runway airport to both assess its behavior and define the attainable level of performance. The outcome of these evaluations is a direct comparison of the aircraft behavior on the tracks, the determination of the level of take-off and landing performances and the identification of the most promising runway cross section."

Page 15, D5.4 final report

Edit: I haven't read it but D3.2 aircraft aspects seems to cover all the flight sim stuff.

SomebodyInTLS wrote:

dtw2hyd wrote:

BaconButty wrote:

Exactly. Depressing how many people are quick to criticise the authors as knowing nothing about aviation, yet are unable to click a link and read a document. The assessment one covers most of the concerns. It would be great to have an intelligent conversation about whether those concerns have been met. And yes, dtw2hyd, plenty of sim time was put in.
http://www.endlessrunway-project.eu/dow ... runway.pdf
Sadly, empty vessels do make the most noise.

There is ton of talk about modelling. I have seen a reference to xplane, but nothing about simulation. Is it available for download, or a video of a human on sim?

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.

"To evaluate operations on the Endless Runway, the most constraining aircraft that is currently in operation has been selected for trial: the Boeing 747, where the outer engine will have the smallest clearance with the ground. The evaluation will be performed with a 6 Degrees of Freedom (DOF) simulation tool. There are several 6DOF simulators available (commercial and free) and all aeronautical research centers developed their own proprietary systems over the years. Flight Gear was selected for use in the project.

The objective of the simulations is to take an existing passenger aircraft and to operate it on an Endless Runway airport to both assess its behavior and define the attainable level of performance. The outcome of these evaluations is a direct comparison of the aircraft behavior on the tracks, the determination of the level of take-off and landing performances and the identification of the most promising runway cross section."

Page 15, D5.4 final report

Edit: I haven't read it but D3.2 aircraft aspects seems to cover all the flight sim stuff.

You criticise people for commenting without reading the report, yet when I read page 9 I find the statement below. The fact that they consider a 747-100 to be a current day aircraft says it all really.

"Based on the open-source software Flight Gear, a first series of simulations has been performed to evaluate
take-offs and landings with a current-day aircraft (B47-100)."

They then state that the ideal aircraft for the circular runway has a T tail and rear fuselage mounted engines. It'll be great to see all those MD80's and VC10's again.

The real clincher though is the part where it says that a circular runway will be 200 to 500% more expensive.

Bongodog1964 wrote:

You criticise people for commenting without reading the report, yet when I read page 9 I find the statement below. The fact that they consider a 747-100 to be a current day aircraft says it all really.

So you didn't read that the reason they took the 747 was because, of currently flying aircraft, it has the most issues with outer engine ground clearance.

Nor, apparently, did you notice that they went through an entire gamut of different aircraft configurations including BWB, double-bubble widebodies and separated-double-fuselage (a la White Knight).

VSMUT wrote:

I have only read the articles superficially, but on a Danish website a commentator noted that the inventor apparently believes that aircraft will be able to fly at slower speeds during a circular landing (as opposed to straight-in approaches of today). That point alone shows how little the person behind this concept knows about aviation.

I mean, it's not like they've devoted nearly a hundred pages to an overview of possible changes from current aircraft that would be necessary to make this happen, right.

Oh, wait. They have.

Again, "I can't be bothered to understand the point; therefore, it's a stupid idea" isn't a convincing argument to anyone with a brain.

bmacleod wrote:

Takeoff/approach paths
ILS
ATC
weather

probably at least 5 more!!!

Too many factors and issues to be considered and answered for this to work.

Except they've, you know, considered them. And they're well aware that this concept would require a major reconsideration and even redesign of all levels of our current air transport system. Which is why they've proposed alternatives that would be more compatible with it. So "X current system wouldn't work with it" isn't really a counter-argument.

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?

Bongodog1964 wrote:

The real clincher though is the part where it says that a circular runway will be 200 to 500% more expensive.

I read maximum 160% for the whole airport according to page 29 (edit: PDF page 29 = report page 28 of D5.4) . Minimum 110%.

Then they state that there will be much lower land area required - which is not taken into consideration in the cost analysis...

Okay, I read D3.2 and guess what

3.5.6 Landings
On a banked circular runway, the pilot has to land on a precise circle at a given speed. Unfortunately, there was no time to implement any assistance to perform the correct manoeuver in Flight Gear. Completing the procedure manually is then a real challenge and differences are observed between the various simulations. In this section, the analysis of one landing simulation is carried out.

I wonder what their thoughts are about landing with breaking action less than good.

dtw2hyd wrote:

Okay, I read D3.2 and guess what

3.5.6 Landings
On a banked circular runway, the pilot has to land on a precise circle at a given speed. Unfortunately, there was no time to implement any assistance to perform the correct manoeuver in Flight Gear. Completing the procedure manually is then a real challenge and differences are observed between the various simulations. In this section, the analysis of one landing simulation is carried out.

In another section on the history of the concept they mention that actual physical tests on banked racetrack in the 1960s showed that the pilots got used to it quite quickly and that the aircraft naturally tracked to the correct banking angle for the speed.

And if implemented then obviously the whole thing will have a lot of automated assistance (this is also discussed at length in the reports).

Their problem doing manual simulation for this project is that (obviously) Flight Gear is not designed to simulate this thing. I have the impression they ran many, many non-manual simulations to get all the crosswind data etc. so you're cherry picking the bit where they said it wasn't easy to "flight sim it" themselves.

CanesFan wrote:

I wonder what their thoughts are about landing with breaking action less than good.

That just means you roll a bit further round the track than anticipated. Unless ATC have really crammed the movements in then you shouldn't end up too close to another aircraft landing or starting a take-off roll - so I don't see it as a big issue. I'd rather have no brakes on this than approaching the end of a wet, straight runway...

SomebodyInTLS wrote:

Their problem doing manual simulation for this project is that (obviously) Flight Gear is not designed to simulate this thing. I have the impression they ran many, many non-manual simulations to get all the crosswind data etc. so you're cherry picking the bit where they said it wasn't easy to "flight sim it" themselves.

They cherry picked one non-manual simulation for analysis. Simulation is very misleading in this context because it is actually a computer modelling. D3.2 was last edited in 2013, they have time to create YouTube videos, but not configuring Flight Gear.

Most modern stealth fighter jets are aerodynamically deficient, ie., there is no way for a human can fly without assistance. Automation in civil aviation didn't reach that level and probably will never.

There is no freaking way a A380(or any) landing gear will survive on a banked circle, if one edge of one landing gear first touches the runway.

Most of the tests in 1960 were on fighter planes with radial engines. There is one reference to c-54 (A318 sized) but no details. There are statements like "some veterans claimed to see".

SomebodyInTLS wrote:

CanesFan wrote:

I wonder what their thoughts are about landing with breaking action less than good.

That just means you roll a bit further round the track than anticipated. Unless ATC have really crammed the movements in then you shouldn't end up too close to another aircraft landing or starting a take-off roll - so I don't see it as a big issue. I'd rather have no brakes on this than approaching the end of a wet, straight runway...

The only time I ever felt like I came close to putting an aircraft off of the runway was in Marquette, Michigan KSAW in an E145. Breaking action was poor and we were right at the crosswind limit. The length wasn't the issue. I came closer to the side than I would have preferred. A curved runway would have made the situation worse.

dtw2hyd wrote:

SomebodyInTLS wrote:

Their problem doing manual simulation for this project is that (obviously) Flight Gear is not designed to simulate this thing. I have the impression they ran many, many non-manual simulations to get all the crosswind data etc. so you're cherry picking the bit where they said it wasn't easy to "flight sim it" themselves.

They cherry picked one non-manual simulation for analysis. Simulation is very misleading in this context because it is actually a computer modelling. D3.2 was last edited in 2013, they have time to create YouTube videos, but not configuring Flight Gear.

Most modern stealth fighter jets are aerodynamically deficient, ie., there is no way for a human can fly without assistance. Automation in civil aviation didn't reach that level and probably will never.

There is no freaking way a A380(or any) landing gear will survive on a banked circle, if one edge of one landing gear first touches the runway.

Most of the tests in 1960 were on fighter planes with radial engines. There is one reference to c-54 (A318 sized) but no details. There are statements like "some veterans claimed to see".

Well it's all a bit moot anyway, since they were using the simulations to verify that it was plausible and look at certain parameters and margins. It wasn't about manual flying.

If the concept ever goes forward then you can bet there will be a crapload of flight dynamics, ATM methods and flight controls development following up on this.

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.

What this study does, whatever it says, is prove that this will never happen.

dtw2hyd wrote:

There is no freaking way a A380(or any) landing gear will survive on a banked circle, if one edge of one landing gear first touches the runway.

Which is, you know, why they talk about changes to aircraft design that would be necessary to make this feasible.

BerenErchamion wrote:

dtw2hyd wrote:

There is no freaking way a A380(or any) landing gear will survive on a banked circle, if one edge of one landing gear first touches the runway.

Which is, you know, why they talk about changes to aircraft design that would be necessary to make this feasible.

You're being extremely condescending for someone with 64 posts on this site and no actual apparent contribution other than to tell people to read the document.

I dont see this happening, but to be fair, this sort of research does have a place, perhaps not the circular runway itself, but some of the other things they learn while researching it.

Remember, 110 years ago the whole concept of flight by heavier than air machines could get you thrown in the loony bin, let alone circle runways...

SomebodyInTLS wrote:

AirFiero wrote:

It appears that every landing would be a side slip or cross control landing, as if into a crosswind. Definitely more challenging.

Actually - even just from the executive summary of the report - that's not true at all. In fact wind conditions are one of the main advantages of this system!

Like I said before; this is not a theme park ride. The total circumference of the track is 10km! Far from being in a side wind "most of the time", the whole point in high wind conditions is to taxi to a point where the whole takeoff run is into headwind!

Just glancing through the final report shows that all the opinionated one-liners on here are completely ignorant of what this concept actually means.

Piedmont767LGW wrote:

Actively flying commercial airplanes for the last 33 years; the impracticality of this ridiculousness is so overwhelming as to make the subject nonsensical.

Case in point...

You misunderstood. I didn't say anything about wind, I said that landing on a banked runway would require banking AS IF one was performing a landing against a crosswind.

AirFiero wrote:

You misunderstood. I didn't say anything about wind, I said that landing on a banked runway would require banking AS IF one was performing a landing against a crosswind.

no, it wouldn't. The banking is there precisely to mean that no side slip is required. The angle of bank should be the same as that required by the aircraft to perform a turn of the same radius as the runway.

A flat curved runway would require side slip or a straight banked runway would require side slip but a curved and correctly banked runway would not.

Fred

SomebodyInTLS wrote:

I see people still aren't bothering to look at the report...

It's not an infinite runway in the sense that you run around and around it and then take off... you just use the most convenient section based on route and, if necessary, wind direction,

In high winds, you still have TWO sections of the track parallel to the wind direction, whatever that is. That is actually an advantage over any existing airport - where even with many different runway headings these will rarely be optimal wrt. wind direction and transition from use of one runway to another will take time.

Closure of a section of runway will therefore limit it in the same way that high winds will... a reduction in capacity, but no more than that.

Correct, there are two sections of a circular runway that would be parallel to the wind. The problem is that only one of the sections will have a headwind, thus in a high wind scenario only one section of the big circle is useful. Unless you are suggesting landings and takeoffs take place going opposite directions around the circle? Maybe that was in the report.

flipdewaf wrote:

no, it wouldn't. The banking is there precisely to mean that no side slip is required. The angle of bank should be the same as that required by the aircraft to perform a turn of the same radius as the runway.

Fred

The angle of bank required for the aircraft to perform a turn the same radius as the runway is airspeed dependent though, correct?

dragon6172 wrote:

flipdewaf wrote:

no, it wouldn't. The banking is there precisely to mean that no side slip is required. The angle of bank should be the same as that required by the aircraft to perform a turn of the same radius as the runway.

Fred

The angle of bank required for the aircraft to perform a turn the same radius as the runway is airspeed dependent though, correct?

it is yes, I believe the runway has a variable bank, similar to a racetrack, steeper on the outside than on the inside. Take off will almost take car of itself but landing more tricky.

Fred

flipdewaf wrote:

dragon6172 wrote:

flipdewaf wrote:

no, it wouldn't. The banking is there precisely to mean that no side slip is required. The angle of bank should be the same as that required by the aircraft to perform a turn of the same radius as the runway.

Fred

The angle of bank required for the aircraft to perform a turn the same radius as the runway is airspeed dependent though, correct?

it is yes, I believe the runway has a variable bank, similar to a racetrack, steeper on the outside than on the inside. Take off will almost take car of itself but landing more tricky.

Fred

Yes, and this is my point. Landing on that kind of runway will be tricky as hell.

What an absurd idea which will never happen.

QueenoftheSkies wrote:

What an absurd idea which will never happen.

More or less absurd than travelling faster than a bullet in a low oxygen environment at -56C in a thin walled aluminium pressure vessel propelled by objects filled with gas higher than their melting point hanging below plastic wings filled with flammable liquid. But yeah, landing on a curve, never gonna happen.

Fred

AirFiero wrote:

SomebodyInTLS wrote:

AirFiero wrote:

It appears that every landing would be a side slip or cross control landing, as if into a crosswind. Definitely more challenging.

Actually - even just from the executive summary of the report - that's not true at all. In fact wind conditions are one of the main advantages of this system!

You misunderstood. I didn't say anything about wind, I said that landing on a banked runway would require banking AS IF one was performing a landing against a crosswind.

Ah okay; my apologies.

dragon6172 wrote:

SomebodyInTLS wrote:

In high winds, you still have TWO sections of the track parallel to the wind direction, whatever that is. That is actually an advantage over any existing airport - where even with many different runway headings these will rarely be optimal wrt. wind direction and transition from use of one runway to another will take time.

Correct, there are two sections of a circular runway that would be parallel to the wind. The problem is that only one of the sections will have a headwind, thus in a high wind scenario only one section of the big circle is useful. Unless you are suggesting landings and takeoffs take place going opposite directions around the circle? Maybe that was in the report.

Yes; that's exactly what is in the report.