Motorcycles and Invisibility

[infrared]

Maybe this is not really my business; we all make our own decisions. I have seen a lot of posts lately saying that auxiliary lighting is the way to be seen, by otherwise careless cagers. I'd mostly agree, but when you are cresting a hill, or the sun is low behind you, any lights (or more lights) can make you even harder to see, and extra caution is needed. I have some back-up, for that statement.

From the day I started riding, experienced riders told me to ride like I was invisible. Good advice, although I did not know why, then. Yeah, had a few close calls. I lived . . . About the worst one for me came from the other side of the problem. I was coming from work, driving the big K5 Blazer (not one of the S-10 toys). I stopped at the Stop sign, and looked both ways. One side had a Sun kinda low in the sky, but not blindingly, yet. The cross street was empty, both ways, but just as I let out on the clutch, I spotted something low, fat and dark, about the size of a wharf rat coming my way. It was clocking about 35 mph (55 kph) down the middle of the road. This was a curious-enough sight to make me lock up the brakes, trying to figure out what this thing was. I heard tires squeal, and a motorcycle appeared, right in front of my truck. There was maybe a yard (meter) between my front bumper and the bike, as it went across my path, but I was fully stopped. The rider had dropped the bike, and slid to a stop. Since he was off already, he decided that we needed to talk. I would have gladly crawled under a rock. I apologized from the heart, but it didn't mean much until I said that I ride, myself, and that I really did look, but just did not see him. No blood no foul; he refused my money. He picked up the bike, and rode away. I was very seriously thinking about mailing in my driver's licenses: trucking, car and motorcycle. My eyes and ears are good. I really DID see something coming, maybe the size of a wharf rat, but that bike had been invisible, in every sense of the word. Two days later, I had the address for the DMV, but couldn't find a postage stamp. I had thought hard about things, and still I had no better answer.

NOVA is a PBS (USA) science-oriented TV program, and I'm always game for more education. That night, the show was about Camouflage Techniques. During WWII, Hitler's U-boats had ravaged the USA East Coast waters, and they could dive fast enough to evade most anti-submarine patrols, even by aircraft. The planes were ineffective as a coastal defense, and they knew it. What our warfighters did then was fairly amazing, for their day. The coastal defense squadrons mounted bright aircraft "landing lights" in the engine nacelles, and in a grid across the noses of their aircraft. These lights got to be called "Yehudi Lights." When the attack bomber sighted any surfaced U-boat, the aircrew went to work. The pilot pulled the throttles down to idling speed, and set the pitch of the props for gliding flight, while diving at the U-boat. The tail gunner had the task of taking a light-meter reading (with a common photographer's light-meter) of the sky behind the plane. Then he cranked up rheostats controlling the light array, to a similar value. By trial and error during practice runs, each plane then carried a written table of rheostat values that would "vanish" the plane even in a bright sky, to any lookout on the surface. Film clips of their practice runs were amazing to watch; the approaching bomber just vanished from the sky. With no sight and no sounds to warn the U-boat lookouts, they learned they were under attack when the bombs came down, and the pilots throttled up their engines to get out of gun range. Many U-boats were lost to these "invisible" anti-submarine planes. In another scenario on the show, an armored troop carrier on a ridge line had been fitted with a grid of lights, and just vanished into sky behind it when the lights came on.

All that to say this: The local bike laws here require riding with the headlight on, both night and day. Most "reasonable" people would figure that this requirement makes us much more visible to other drivers, and that is mostly correct. However, when the sky is bright behind you, it can be worse to have the headlight ON, than OFF. Extra lighting really may make things worse. I had looked for crossing traffic at that Stop sign, and there was no visible vehicle coming. That rapid "wharf rat" that I DID see was actually the very bottom of the front tire on that bike, because it was far enough away from the headlight to be seen. No other part of that "vanished" bike had been visible, though. Expect to be truly invisible, with the headlight on, and a bright sky behind you. The "glitter" of the pavement sands had made the ground look as bright as the sky to me, on one very scary afternoon. At least, now I knew how this close-call had happened. I put my driver's license back into my wallet, but now I'm extra careful riding, when the Sun is behind me. For your own consideration, then . . .

From the Web:


https://www.infosources.org/what_is/Yehudi_lights.html

https://www.wired.com/dangerroom/2008/05/invisible-drone/

"During WWII, The US Navy's Project Yehudi used lights mounted on the leading edges of the wings of a torpedo bomber to successfully hide the plane in broad daylight when attacking a submarine. Visual detection range in the tests dropped substantially from 12 to 2 miles. As the plane approached a target, the lights, which pointed forward . . . the output intensity (not color) of the light was set to match the intensity of the sky behind the approaching plane. This effect takes advantage of a physiological phenomenon termed isoluminance where objects of similar intensity can be indistinguishable from one another under certain conditions."

Cheers,

Infrared

 

[bluesdog]

I wonder if having an array of lights of differing or even varying intensity and spectrum would make a difference? The article specifically refers to, '... the output intensity (not color) of the light was set to match the intensity of the sky behind the approaching plane'

I've noticed that bikes with single headlights appear much less visible. By contrast, I've noticed trucks with various colored running lights, of varied intensity, are quite conspicuous. Of course, the trucks present a larger aspect, as well.

Another consideration: The human visual perception system is less adapted to perceiving oncoming objects approaching directly, whereas it is much more sensitive to lateral motion. That's why I 'weave' the bike a little when approaching an intersection, or see a vehicle waiting to enter from the side.

OTOH, I've witnessed cagers completely oblivious to emergency vehicles with all lights flashing, sirens wailing etc..

Just keep riding as if you were invisible. Except, of course, to the LEOS

 

[Pterodactyl]

I don't agree that running bright aux lites during the day can camouflage the bike. My experience as a rider and a driver tell me that your transference of what you learned about using light in WWII to riding a motorcycle is not relevant. I've had many riders and drivers comment about how my LEDs enhance my conspicuity. They may or may not save me from an accident but I think they shift the odds in my favor. Just my opinion.

By the way, I too have pulled out in front of a bike. In my case the bike swerved and I stopped before I was very far out into his lane. A maddening and humbling experience; thankfully not a tragic one.

 

[SoCalFJR1300]

I have a riding friend in Phoenix that puts a switch on all his bikes to turn on and off his headlight.

He rides with it OFF during the day.

I asked him why he does this becasue it has to make him more visable during the day.

He said there were studies done in Europe that show daytime headlights do no more good than no headlights at all.

Not saying I agree with that but that's why he says he turns it off.

 

[Geezer]

I use a headlight modulator and I know that it helps people notice me.

 

[leclairk]

Almost everyone has heard of it but I don't see many bikes on the road using it. Anytime I approach an intersection with a cage on one side I do this. The SMIDSY, hope the link works.

 

[Warpdrv]

Good Post - thanks for the link to the video....

 

[PhilJet09]

Interesting post, I learned something new. My only consolation is that my aux lights have a much different output intensity than my headlight. Still, I'll keep this in mind when the sun is on my back.

 

[Donal]

Another take on the same subject of motion camouflage and motion induced blindness

 

[RaYzerman19]

I've done a lot of observing to see what makes bikes visible. Next time you're in a group (at the front), look in your mirrors to see who stands out and who doesn't. The human sees better when there is contrast. A single headlight is more visible when there are fork lights installed, which create a triangle. Usually LED lights are more blue than the whiter/yellower headlight, another bit of contrast. I believe you are even more visible if one or both of the fork lights are amber, a greater contrast to the background behind you and yellow being a more readily visible colour (although the bluer LED's are quite good, IMHO). Fork lights also move more dramatically than a headlight when you weave. They're also low enough so oncoming traffic can still see your turn signals, provided you don't have overly strong retina burning lights.

Another thing that makes you invisible is a headlight that is aimed too low...... looks dim or non-existent at greater distances....

 

[Wlfman]

Triangle of lights, with the two lower ones in amber/yellow(aka Fog Lights) will get you seen.

 

[infrared]

I don't agree that running bright aux lites during the day can camouflage the bike. My experience as a rider and a driver tell me that your transference of what you learned about using light in WWII to riding a motorcycle is not relevant. I've had many riders and drivers comment about how my LEDs enhance my conspicuity. They may or may not save me from an accident but I think they shift the odds in my favor. Just my opinion.By the way, I too have pulled out in front of a bike. In my case the bike swerved and I stopped before I was very far out into his lane. A maddening and humbling experience; thankfully not a tragic one.

Kevin,

I did not say that lights can camouflage a bike in daylight, in ordinary situations. The problem arises when the sun (or a bright sky) is behind you, and you have one or more lights bright enough to match the brightness of your background. When cresting a hill (with the sun behind you), you may be very difficult to see. If your shadow is long and straight out in front of you, sunlight may reflect from the sand crystals in the roadway, making your entire background (road and sky) very bright to drivers looking for you in the bright sunlight. This is the situation where headlights can make a bad deal even worse. I would doubt that any one "fix" will cure this problem, but you need to be aware of this difficulty, and take extra precautions concerning your safety. A coffee break may be all the time you need, to let the light conditions.change enough to be safer.

A shiny windshield can also be a factor, there. It may reflect the color and brightness of the sky to other drivers, making your bike appear much smaller than you might think.

Cheers,

Infrared

 

[Justin]

One major problem for motorcycle is that people perceive thr single bright headlight of a motorcycle as the headlights of a car much farther away. That is why the triangle of light is very effective. I don't have a triangle of light, but I have 4 aux LED lights that I run dimmed to 10-20% during the day. They are bright enough to be seen, but the light isn't so intense they all blend together. I feel much more visible when I ride with extra lights, but I still ride like nobody sees me.

 

[900gc]

Light triangle w/aux. lights, variation in light color, flicker/twinkle/modulator devices Hi-Viz gear, reflective mat'l., secondary brake/tail lights, etal.

I take advantage of most all of the ways to be seen better. Are there some rare circumstances where none of this helps? Probably, but what can you do about it except be aware of the conditions and ride defensively.

As for riding with no lights;

Last year when preparing to merge onto a two lane, high speed road (in my car) from an aux. road (no entrance ramp lane at all, you have to merge into traffic from a dead stop!), the shadow of the overpass of the aux. road obscured my view of a motorcycle that was under the overpass. The bike turned out to be an older Sportster with no headlight on and the guy was wearing, what else, black. He blended in perfectly with the shadow. I ALMOST pulled out in front of him, and with the very short distance from the ramp to him, I doubt he could have avoided me in time IF I had pulled out. Somehow he registered just enough in my brain for me to think, "did I just see something"? so I looked again.

That small, weak Sportster headlight would have been like a lighthouse in that shadow if it had been ON.

 

[Bearly Flying]

Regardless of any lighting systems you have on your bike, ( and that's a good thing).

THEY are still out to KILL you, ride accordingly......

 

[bluesdog]

I've done a lot of observing to see what makes bikes visible. Next time you're in a group (at the front), look in your mirrors to see who stands out and who doesn't. The human sees better when there is contrast. A single headlight is more visible when there are fork lights installed, which create a triangle. Usually LED lights are more blue than the whiter/yellower headlight, another bit of contrast. I believe you are even more visible if one or both of the fork lights are amber, a greater contrast to the background behind you and yellow being a more readily visible colour (although the bluer LED's are quite good, IMHO). Fork lights also move more dramatically than a headlight when you weave. They're also low enough so oncoming traffic can still see your turn signals, provided you don't have overly strong retina burning lights.
Another thing that makes you invisible is a headlight that is aimed too low...... looks dim or non-existent at greater distances....

+1

This is how I roll now --

I still do the weave when approaching intersections, etc...

 

[Lauren_TK]

I've done a bunch of research on camouflage . . . for my own fun and amusement. I like to spend significant time in the library system investigating random subjects. In short, I shouldn't be confused with a real expert on visibility.

Having said that, my reading indicates that no camouflage system can be 100% effective. My take away from my reading as it applies to being seen, is that I do not believe we can find a visibility solution that will work 100% of the time--even if we exclude oblivious drivers from the calculation.

In my option, if we come up with a combination of gear (lights, reflective/hi vis clothing, etc.) that yields 99.99% visibility, we should still ride like we are invisible.

 

[Nanahanman]

That video gives excellent advice and I will add it to my defensive driving. Thanks for posting.

I have the LEDs on the forks and others have said it makes a BIG difference to visibility.

When in the city, use low beam headlight only.

This does 2 things.

First, the signal lights are not washed out by the intensity of the bright high beam headlight.

Second, it gives me the high beam option to go to and adds to the change in visibility.

 

[hppants]

During daylight hours I run high beams always. My fork mounted LED's have increased my visibility tremendously. I know this by the way vehicles traveling toward me now act.

In May while running one particular stretch of The Dragon, I was pulled over by a Tennessee State Trooper. I absolutely was not speeding, on coming bikes for a mile had been warning me to slow down with the courteous pats on the helmet. I told the trooper:

"Surely you haven't pulled me over for speeding?"

To which he replied:

"No, those lights you have down there are way too bright"

(Pants) "Let me get this straight. You are telling me that I'm too visible to on coming traffic and you want me to tone it down?"

(Trooper) "Exactly - adjust those lights as soon as you can."

(Pants) "Yes sir - I'll get right on that." (wink wink)