Shawnee, I feel for you; since I'm having car trouble too, I can say with authority, it sucketh!

What????

:headshake

Thanks Cloud, I feel your pain too!

What? Does that make sense to you?

It makes sense to me, but I think it's total BS.

TW is saying that in WWII, airplanes would turn their wing headlights on so that they could sneak up on submarines in broad daylight. He's saying lights made the planes less visible. Therefore, daytime running lights on cars are not effective at making cars more visible. TW thinks daytime running lights are stupid.

I personally find it easier to see cars with their daytime running lights on, because cars today are mostly all the same basic invisible color. Some sort of silver/gray/tan. They blend into the road and the background. I like daytime running lights.

Agreed.

How did the lights make them less visible? This makes no sense.

Agreed.

If you're chillin' on the deck of a U-boat you scan the sky for dark dots against the bright sky, lights along the wing may mask that sillouette... [shrug] I think the running lights are effective as well.

Accidents in Canada went down 11% when DRLs were introduced.

When do most crashes occur? During that hour after dawn and hour before dusk. And during rainy weather when headlights are also necessary so that others can see you. That 11% number says why headlight on before dusk and after dawn saves lives. The reason why: because that is when the human eye is least effective at seeing other vehicles and therefore why the DRL is most effective.

What vehicles are hardest to see without headlights on? Red. DRL corrects a major driver mistake. Too many drivers October through February fail to always turn on headlight on every day when commuting to and from work (8AM and 5PM). Too many drivers foolishly think headlights are for you to see the road. #1 headlight function - so that others can see you especially when most crashes happen - dawn, dusk, and inclement weather. Headlights on a sunny mid day may actually make the car slightly harder to see. But that is not when headlights are required and critically essential to avert crashes. DRLs are only correct bad driving - people who think headlights are only for seeing in the dark. DRLs with photocell would be even better because headlights at dawn, dusk, etc would be full brightness - all 55 watts.

DRLs were just as effective when using a photocell as xoxoxoBruce described. That was how it was done in the 1960 before marketing subverted the function to increase sales.

I've described it elsewhere I but hold that the modern fashionable silvery-gray with a dash of brown is much, much harder to see than red. Just based on my personal experience.

The bit about the planes and U-boats is plausible. I've heard that some squid produce bioluminescence to prevent casting a dark silhouette when seen from below. I don't think it works for cars, though.

I remember hearing about this when I was in the military. I think it's called active camouflage, which, for aircraft, is probably most effective with pale blue lights.

The technique was not used long. Radar made it easier for planes to get on top of a Uboat faster and to do so in inclement weather and at night.

With Ultra, they knew where to look. With radar, the Uboats were found quickly even when Uboats resorted to snorkels.

Anybody want to sink a German car?

I always thought headlights in the daytime would make a car more visible...at first. Because, when only a few cars had headlights on in daytime they stood out, so you noticed them.

When every car has headlights on in the daytime, they all begin to blend together again.

For me, I am having a giant torch attached to the lid of my car, with sparks that shoot out, and lazzzzzzzzzzerrrrrrrrrrrs.

They'll see ME.

Shawnee, a serious suggestion if I may.
It seems very strange that the lights both work, but have become less bright.
Can you find someone with the same make and model car, park side by side facing a wall at night, and compare headlights? Just to check if yours are in fact dodgy. And what a pick-up line! Wanna see my high-beam?