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USCG Alert regarding LED lights

Posted: February 2nd, 2016, 6:10 pm
by SplashyLady
The Coast Guard wants to be sure lights are up to spec - good info here:

http://www.uscg.mil/hq/cg5/cg545/alerts/1015.pdf

USCG Alert regarding LED lights

Posted: February 3rd, 2016, 10:51 pm
by Lyndon670
Another interesting point of conversation regarding LED lights for navigation. I am a police officer operating a police helicopter - amoungst the regular police details that we do we also perform search and potentially rescue details. We work along side the Coast Guard when requested. I can tell you that LED lights do not show up to any search parties operating with Night Vision Goggles (NVG) - which is how night searches are mainly conducted. It is a very small factor to consider when converting to LED lights for navigation lights, but it is a concern none the less.

USCG Alert regarding LED lights

Posted: February 4th, 2016, 1:09 am
by RGrew176
Lyndon670 wrote:
> Another interesting point of conversation regarding LED lights for navigation. I
> am a police officer operating a police helicopter - amoungst the regular police
> details that we do we also perform search and potentially rescue details. We work
> along side the Coast Guard when requested. I can tell you that LED lights do not
> show up to any search parties operating with Night Vision Goggles (NVG) - which
> is how night searches are mainly conducted. It is a very small factor to consider
> when converting to LED lights for navigation lights, but it is a concern none the
> less.

Thanks for posting this very valuable information. I did not know that LED lights did not show up when using night vision equipment. I had no intent to change any of my navigation lights to LED but I will look into changing my interior lights to LED's this upcoming season.

USCG Alert regarding LED lights

Posted: February 4th, 2016, 8:18 pm
by Viper
Lyndon670 wrote:
> Another interesting point of conversation regarding LED lights for navigation. I
> am a police officer operating a police helicopter - amoungst the regular police
> details that we do we also perform search and potentially rescue details. We work
> along side the Coast Guard when requested. I can tell you that LED lights do not
> show up to any search parties operating with Night Vision Goggles (NVG) - which
> is how night searches are mainly conducted. It is a very small factor to consider
> when converting to LED lights for navigation lights, but it is a concern none the
> less.

Lyndon, I had heard of this pertaining to red LEDs but not other colours. I also thought that the newer generation units were better at handling that now. Is this not the case?

You seem to have experience with these so perhaps you can enlighten us with some real world experience as apposed to what we are led to believe. When performing a search using NVG, are you relying on the lights on the vessel or ambient light from say the moon, stars, and other light sources near by? I guess the more detectable light the better?

Are infrared imaging devices not used in searches? They wouldn't rely on available light and would only apply in certain circumstances where a heat signature is present but another good tool in the search arsenal I think.

Your thoughts?

USCG Alert regarding LED lights

Posted: February 4th, 2016, 8:30 pm
by Lyndon670
You guys are on the right track. We also use FLIR type equipment (FLIR is synomous with the equipment but is also a brand name - kind of like the Kleenex brand) - which looks for different temperature frequencies in the light spectrum. That is "mombo-jumbo" but breaks down to this: FLIR cameras look for differences in temperature. And therein lie the problem. To use a FLIR camera, you are aiming a camera lens at the area you want to search. In otherwords you are limited to the field of view of the camera. The more narrow the field of view, the closer the target is. The wider the field of view, the further away the target is. To sum all of that up, FLIR is great for fairly close searches - IE backyards, shorelines, even open fields. But, for large area, it simply is ineffective due to the limits of the field of view. FLIR also does not see the LED light as there is no "temperature" to them. But, with the FLIR, I can pick up on all of the other "heat signatures".

NVG's are great because they see the whole picture - we flip the lenses down on our helmets and see every bit of traditional light possible. For example, we had a couple of young girls lost in a large wooded provinical (national) park a couple of years ago. It would have taken hours, perhaps days to perform a grid search and fly with the FLIR camera to locate them. With NVG's it was a simple as - believe it or not - having them open their cell phones. We were able to see the light from miles away with the NVGs. The NVGs look for the light, not the temperature frequency. Because LEDs are so far down on the temperature frequency spectrum, they remain invisible to current NVGs. There is possibly military spec NVG technology being used in the especial forces, but not by search and rescue units.

Again, for nearshore operation or small lakes- I have no issue with LED nav lights. But if the body of water is big enough, it is just something to consider.

USCG Alert regarding LED lights

Posted: February 4th, 2016, 8:38 pm
by Viper
Makes sense Lyndon.