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Im still suggesting my rho shape variant of this idea. You have a straight runway with enough distance to land but then have the circle for slowing down once landed.
I'm thinking if we ever figure out a way to reduce airport foot prints it could drastically drop housing costs. There are hundreds? Of acres of prime urbanish land. Look at Boston for example. I wonder if they take the opportunity cost of having an airport there into the cost of flying? That land could be worth 100 billion??
One interesting data point in that regard is Berlin's Tempelhof Airport (which you might remember from Indiana Jones 3). It's extremely central because it was one of the first commercial airports and was shut down a few years ago.
It's a park now and will probably remain–the plan to build even a few houses was killed by a referendum. It's also a really fascinating place, because it feels entirely unlike a normal park. There are very few trees, so it's much more open. The runways remain unchanged, and it's quite an experience to jog there, with all the history that place has seen always on your mind. (https://www.google.de/maps/@52.4760745,13.3994616,3a,75y,279...)
Im still suggesting my rho shape variant of this idea. You have a straight runway with enough distance to land but then have the circle for slowing down once landed.
That won't work. Normal small airports that only have one runway use the runway in both directions, depending on wind direction. You never land with a tailwind, and you never take off with one either. A rho shape wouldn't work here because the circle is only at one end, preventing bidirectional use.
As an airline pilot flying Boeing 757 and 767 I think this concept is really cool but it does overlook some fundamental principles of the unreliability of weather in order to be practical. This week I have landed in variable winds gusting up to 45 knots and then every inch of wingtip clerance counts, a drawback of this design. What if the aircraft makes a long landing (floats) and suddely faces a different wind compo…
Correct me if I'm wrong, but I thought the whole idea behind the circular part was so that doing a crosswind landing would be "easier", because you could setup the landing so the crosswind pushes your towards the center...
There can be pretty severe shear at different altitudes on the way down, and the wind can flip direction any time it wants.
Earlier quoted context omitted.
Given a radius of a curve and bank angle it is simple to calculate what the minimum required speed is to have 0 lateral force
If only airplanes all landed and took off at the same speed. Actual take off and landing speeds will vary depending on the aircraft's characteristics, fuel/passenger load, wind conditions, and density altitude (which varies depending on temperature and humidity). So the idea that you could build a runway with a bank angle that produces 0 lateral force for all aircraft is just not possible. Sorry.
> If someone one hundred years ago would have said that we would be transporting as many passengers in aircraft as we would in trains, people may have thought , "a steam engine would never fit in an aircraft made of wood and ropes". That's such an eloquent way of highlighting the need for conceptualisation in engineering but also the struggle to convince others (investors perhaps) that you're not a complete nutcase w…
We're already trying to build a space elevator when we don't even know what material can possibly withstand those forces. It's something over the horizon, but we're hopeful we'll find it. Likewise, powered flight was possible, the only problem was finding lighter, stronger materials for the airframe and a lighter, more powerful engine to fly it.
I'm thinking if we ever figure out a way to reduce airport foot prints it could drastically drop housing costs. There are hundreds? Of acres of prime urbanish land. Look at Boston for example. I wonder if they take the opportunity cost of having an airport there into the cost of flying? That land could be worth 100 billion??
It's too early to tell if experiments like Lilium are successful (http://www.theverge.com/2017/4/20/15369850/lilium-jet-flying...) but that could completely upend the entire aviation industry if proven more cost-effective.
Earlier quoted context omitted.
Given a radius of a curve and bank angle it is simple to calculate what the minimum required speed is to have 0 lateral force
If only airplanes all landed and took off at the same speed. Actual take off and landing speeds will vary depending on the aircraft's characteristics, fuel/passenger load, wind conditions, and density altitude (which varies depending on temperature and humidity). So the idea that you could build a runway with a bank angle that produces 0 lateral force for all aircraft is just not possible. Sorry.
Frankly, the circular design isn't ambitious enough, as initially proposed.
Earlier quoted context omitted.
That won't work. Normal small airports that only have one runway use the runway in both directions, depending on wind direction. You never land with a tailwind, and you never take off with one either. A rho shape wouldn't work here because the circle is only at one end, preventing bidirectional use.
But for larger airports it would.
Im still suggesting my rho shape variant of this idea. You have a straight runway with enough distance to land but then have the circle for slowing down once landed.
That won't work. Normal small airports that only have one runway use the runway in both directions, depending on wind direction. You never land with a tailwind, and you never take off with one either. A rho shape wouldn't work here because the circle is only at one end, preventing bidirectional use.