You can circle to land if the approach is only one direction. Basically shoot the approach to minimums. Tower will say, circle to land north/south and you fly a normalish pattern, lower to the other end of the runway.
I am also a pilot. I'll add to this by explaining a couple of basic principles in flying aircraft.
The #1 reason this is a very bad idea is it is not compatible with flying what's called a stabilized approach, which is fundamental to safe landings. What this means simply is you fly your last (final) leg of approach on a straight line aligned with the centerline at a shallow glide angle. The moment before touch down you reduce engine power and flare (bring the nose up) and stall the wings just above the runway. If you are flying into a crosswind, you crab (fly with the nose angled into the wind to stay on centerline), then kick out of the crab angle just prior to touchdown (you control the rudder with foot pedals). A banked circular runway is totally incompatible with this. If you misjudge your approach a bit and land long, you miss the runway. You have to go from wings level to a banked turn at exactly the right moment. Lots of potential for things to go wrong. It's just a bad, unsafe idea.
Another reason this is bad, higher landing speeds. If you are flying in a banked turn, your wing will stall at a higher airspeed. Heavy aircraft already land fast, and anything that adds to that creates problems, wear on tires and brakes, etc.
These people also seem to be unfamiliar with basic geometry. A "circle-ish" runway configuration would do the job while retaining long straight runways. For example, just arrange eight runways in an octagon configuration, with the airport terminal etc in the center. If you have enough land area to work with, this is easy. The problem, of course, is that land in large metro areas is expensive, so you end up with compromises such as intersecting runways as you see at airports like San Francisco (SFO).
So while this may be fun as a flight simulator challenge, it is a bad, unsafe idea for the real world.
How would a circular runway affect inbound emergency aircrafts?
My intuition tells me that a straight runway would be less burdensome on the flight crew. You set up for your approach then you can go back to dealing with the issues at hand.
That doesn't make too much sense, as runways vary enormously in length, and airplanes vary enormously in how much space they need to land.
A loaded-up B-52 landing in no wind on a 5,000ft runway needs to touch down right at the beginning and even then it's going to be touchy. On the other hand, I could land my ASW-20 in a 20kt headwind 14,800ft down a 15,000ft runway and be entirely comfortable.
Of course, everybody tries to land near the beginning because it increases your margin for error, but it's not strictly necessary in many situations.
Circle to land requires visibility, you need to keep the runway in sight during the whole maneuver. So that wouldn't really have helped them in this situation.
Wow, there are so many reasons this is a terrible idea.
1. It doesn't actually solve the problem it sets out to solve (crosswind landings). To the contrary, a circular runway guarantees that if you have any wind at all then you will have a crosswind at some point in the landing. Not only that, but the apparent wind direction will be constantly shifting during the landing, making the landing even more difficult than a normal crosswind landing.
2. Flying in a circle at a low airspeed and at low altitude is absolutely the single most dangerous thing you can do in an airplane. When you are flying in a circle, the outboard wing is moving faster than the inboard wing, and so if you are flying close to stall speed the inboard wing will stall first, resulting in a spin. It is possible to recover from a spin but you have to descend in order to do it. If the spin starts at low altitude there is nowhere to descend to, so you will crash. Spins on approach to landing are one of the leading causes of fatal crashes in small general aviation aircraft.
3. Airport approach and departure procedures are designed around the fact that runways are aligned in particular directions.
The whole point of a stabilized approach is to avoid unnecessary maneuvers in the final moments of flight, and to simplify decision making. Your approach is a straight in powered glide. If you like where you end up, you cut power, flare and land. If you don't like the situation, you apply full power and climb straight ahead, then turn according to the rejected landing procedure for the runway or ATC instructions.
What you describe needlessly adds complication to the approach, which adds risk, which will certainly result in accidents and fatalities. It's just a bad idea, and there is a reason airport designers never considered this (it is not as if the idea of banked curved roadways is new).
Sorry as a pilot, I can say this is not just a bad idea, it is a lethally bad idea. A fun simulator challenge, but not something that will work in the real world. If you are doubtful, I would suggest you try circling around a point in IFR conditions within 50' lateral tolerance above a circular runway. Be sure to add zero visibility and a 10-20 knot cross wind to simulate doing so in the clouds above the runway as you descend.
You never land with a tailwind and if the wind shifts the airport simply change the runway to the opposite one. If you use a circular runway and landing with a cross wind you would during your landing roll be subjected to a tailwind.
Sure, you could stop using that part of the runway but then we're back at the practical economical argument for this design.
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.
The point being that it doesn't need a runway. There might be opposition to changing the rules, but rules intended for planes that needs to land at an airport makes little sense for something that can land on pretty much any small flat-ish surface.
True, but not every approach to an airport is a nice constant vector.
Continuous descent operations are the optimal, but there's plenty of suboptimal airport approaches that require level flight at a height where fuel efficiency is far less than at cruising altitude.
Yeah, the only real possibilities for landing on a runway are insanely long runways (dozens of miles!) or high-speed arrestor cables, like souped-up versions of those used on carriers. And even then, the super-wide maneuvering radius means flaring without stalling is practically impossible - you'd need to clear a long area in front of the runway so you can basically come in almost flat.
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...
Things are conventional because they tend to work well. And part of working well is being resilient to errors and non-optimal situations.
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