Should we be using circular runways?
http://www.bbc.com/news/magazine-39284294
Quote from: Will on Sat, 18 Mar 2017 14:06
Should we be using circular runways?
http://www.bbc.com/news/magazine-39284294
Thought up by a Dutch guy, should be ok!
Jeroen
The higher the turn rate (which increases with groundspeed), the higher the required bank angle. The runway's bank angle is fixed, so the aircraft's bank will not be coordinated with the turn rate for 99% of the time; there will be a side force on the tires. Can this be neglected?
Also the g-force will be higher than 1.0, i.e. the wings must generate more lift; the VR speed must be higher. Is this a significant disadvantage?
How's the aircraft handling on a 2 E/O takeoff? Can you keep the aircraft not only straight with full rudder deflection, but more than straight into the runway turn direction?
Can evacuation procedures and rescue vehicles operate normally on the tilted runway surface?
Is it really better than a 4-runway-quadrant layout, or a 3-runway-triangle layout like in Tel Aviv, for example?
|-|ardy
I agree that the inventor doesn't answer all of the physics questions involved. He talks about landing three aircraft at once, with touchdown points at three different places within the circle. But since a high-speed aircraft will soon be landing at a spot where a low-speed aircraft is decelerating, there's no way to reduce the side loading to zero. So some aircraft may have no lateral force but above 1G vertical force, others will have lower vertical force but much higher side loading. It sounds unworkable.
All technical details, guys. The market will solve all of these just by making the opportunity available. Drop the rules and wait!
Jeroen
Haha! Make Runways Great Again!
Seriously though, we haven't innovated much in the realm of takeoff and landings over the last 100 years. The old story still remains, that the aircraft launches and recovers entirely under its own power. Circular runways may be a bit of a stretch, but I wonder if there isn't room for some sort of new idea.
What about sudden wind changes once you get above the lip of the "crater". If the slope is shallower, your wind direction will be constantly changing.
How difficult would it be to move all that earth to form the slope?
During rain, will the crater fill with water?
At low speeds, will fuel pour out the wingtip on the lower side? Will some tank pump fuel inlets be uncovered?
If a fire breaks out on the upside wing due to a fuel leak, after stopping, will the fire immediately go towards and under the fuselage (preventing evacuation on both sides)
I suppose it's good during brake failures and RTOs... The runway is endless.
Also good for noise abatement.
I had to check the date... Too early for April 1st ;D
Never run out of runway any more! Imagine the possibilities! The savings! No more V1 calls! No more V1 cut training! No more balanced field sillyness! We have been holding ourselves back for much too long! Cut the c**** and let the entrepreneurs do what they do best!
It's a rubbish idea; highly flawed.
I presume the calculations would now be done in radians..
Peter
I don't see it happening. On a straight strip you can see aircrafts (even of the same type) landing at different positions (even on an ILS approach) and this type of runway will require to aim to a very specific point (a required precision of a landing on a carrier) even before the landing itself and then not only the pilot will have to concentrate on the final descend rate, he will also have to keep a very specific bank angle and turn rate (and the aircraft ahead of him).
This will be accident waiting to happen.
But it's not 'Fake News' ... it's from the BBC right?
Quote from: G-CIVA on Fri, 24 Mar 2017 11:20
But it's not 'Fake News' ... it's from the BBC right?
Purveyors of the best fake news... Excellent fake news...
Thanks to colleagues, two pointers to old (1960s) articles about circular and other runway arrangements.
https://books.google.fr/books?id=2CkDAAAAMBAJ&pg=PA77&lpg=PA77&dq=Popular+Science+in+1966+circular+runway&source=bl&ots=nvgEQXeb81&sig=SBcfjj8kOik8stK-ULgPJwOCUkQ&hl=en&sa=X&ved=0ahUKEwi0qMv9s_nSAhWKLMAKHUJcDo0Q6AEIHzAB#v=onepage&q=Popular%20Science%20in%201966%20circular%20runway&f=false
http://archives.chicagotribune.com/1950/04/03/page/54/article/a-glimpse-into-the-future-how-chicagos-great-ohare-airport-will-look-in-1960
I found that this article conveys the basic limitations of a circular runway in a fairly well-organized fashion:
https://theconversation.com/this-fantastic-idea-for-a-circular-runway-is-sadly-going-nowhere-76612
While it's aimed at the general public, I thought it communicated many of the biggest unsolved (unsolvable?) problems in a clear, precise fashion.
Sorry to bring this old topic up, BUT somebody actually made the effort and posted a take-off and landing video from such RWY.
https://www.youtube.com/watch?v=VIlTV3fHn3M (https://www.youtube.com/watch?v=VIlTV3fHn3M)
Landing seems to be very difficult to say at least.
Cheers,
If ever, this will guaranteed be a 100% robot landing. Humanly too dangerous. Machine? Possibly -- if everything works. Not necessarily more dangerous than a LAND3 in true nil vis, if proper escape procedures are in place. Once on the ground, everything better work properly, though.