Runway color

[flyguy]

Anyone else notice this. I started noticing this a while back and have seen it so often and so consistently that I am sure that it is real.
Light colored runways are much easier to land a taildragger on than dark colored ones.
Our home airport was recently resurfaced and is quite dark. Ever since then I have had troubles finding the ground. Pick one, bounce it or drop it in.

In contrast, every time I land at a local x-Army field that has light brown pebbles in the runway material, and is quite light colored, I roll it on.

We have a hot-springs spa back in the hills that has a narrow dirt strip of light tan color. Even with the distractions such as dodging gopher holes I still put it on smooth almost every time.

I'm pretty sure this is the same thing that happens when you try to play tennis at dusk. The ball is never where your eyes/brain averages it out to be due to the lack of light. I suspect a lack of "texture" information coming back from the black runway makes it even worse.
Darryl

[Vasey fan]

Re: Runway color

I've never noticed a difference, I'll have to play with that.

Different runway widths tend to be more of an issue, but you can minimize that by training yourself to get more info from your peripheral vision.

[flyguy]

Re: Runway color

You have a good point there. The narrow dirt strip seems to be the easiest to get a precise touchdown. It has uneven edges with dry weeds, some loose dirt and little holes, all right where I look for depth perception.
I think I might try landing closer to the left edge of the runway, see if that makes a difference. It is about 50 ft across.

Interesting how one can fly for years and still learn something new almost every day.
DC

[mulwyk]

Re: Runway color

Ok, I could be way off on this, but I always heard it was a question of "texture" or "contrast". Like a smooth, black surface (water at night for example) would be the most difficult to land on because it's so difficult to judge distance to the landing surface. The easiest to land on would be a white surface with, maybe, yellow triangles painted on it because it would be easy to judge height above the surface.

I was always able to make a perfect 3 point landing on our farm strip...a narrow dirt track with foot high weeds on either side. But on a long wide concrete "airport" runway I'd bounce it high nearly every time. It wasn't a question of color, I don't think, but a matter of reference, of having a scale reference (those weeds?) to judge height.

[M Jones]

Re: Runway color

All pretty interesting thoughts. Having a reference, like the weeds, and a narrower runway does make sense. I hadn't really thought about it that way, but I do know that I usually make better landings on those 'green' runways we have around here most of the year.

[Mark Julicher]

Re: Runway color

Landing cues vary from pilot to pilot. I have not noticed a distinct difference from concrete to asphalt, but I can tell you from experience that a wide runway will lead to a high flare and dropped in landing if you are not prepared for the visual cues. The USAF's B-52 bases had 300 foot wide runways. I always took students to these locations at least once during training and it was a remarkable experience for them. Due to the overwhelming tendency to flare high, the USAF eventually painted these wide runways to provide standard 150 foot wide edge stripes. That is still a very wide runway if you are used to a typical municipal airport.

I was a USAF instructor when the first military simulators were equipped with first generation visual systems. I noted a strong correlation between flight time and ability to land the simulator. High time pilots almost universally pranged on with a late flare. Low time pilots always landed the simulator much better. The early visual systems had limited visual cues and so the fine details important to a higher time pilot were not available. The low-timers were not using peripheral vision and fine detail and it did not affect them so much when these were absent. This was exactly reversed in the aircraft where the old heads had plenty to see could judge altitude and sink rate.

The low-cue situation is very similar to glass water landing, desert landing, or snow field landing, and to some extent night landing. Anything that can be used to increase visual detail is good. As a pilot learns to scan more of the runway - near - far - edges - etc. landings improve, but take away the cues and it requires a big adjustment.

Later generation simulator visual systems added a lot of detail, especially in the approach and landing areas.

[flyguy]

Re: Runway color

It probably would have been more accurate for me to refer to the amount of light reflected back from a wide runway instead of the color.

Your eye will integrate the information coming from a moving object and give you an average position that gets further from the real position as the amount of light reflected from the object diminishes.

Very interesting demonstration: Remove one lens from a pair of regular sunglasses (not Polaroid?) and wearing the glasses swing an object suspended from a string back and forth in front of you. The object will look like it is swinging in an ellipse, not a straight line. It is very strange looking. Cause is: both eyes see the object at the same place when it stops at the end of the swing, but they get different "integrated" positions when it is moving. Your kids will really get a kick out of this if they haven't seen it before.

Same effect from landing with lessened light reflected from the surface (if that is all you have to look at), although I always figured that I was more likely to fly into the ground at dusk or night as opposed to dropping it in. Have to think about that some more.

The very wide runway effect may be even more troublesome than the black asphalt surface problem.

Interesting input from you guys, thanks.
Darryl

[flyguy]

Re: Runway color

Did some landings this AM and moved them over to the left edge of the runway on our midnight-black new asphalt. Rocks, grass, and landing lights over there where I was looking. Wow, seemed so easy. Not perfect roll-on's, but had it right down there and could tell exactly what the plane was doing.
It is always possible that I was just working harder, but it didn't seem that way. Just seemed, well, easy. You can't say that about Taylorcraft 3 point landings very often. Chuckle.
Darryl