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HVVega 01-24-2011 10:22 PM

Dangers of LED navigation lights
 
I just wrote this in response to another thread but it struck me as so important I thought a new thread was called for.

I was having a beer with my friend who skippers about 50,000 tons of bulk carrier and he made a very interesting observation. Twice they have had to sheer off hard - not easy for a boat that size - because the color of "white" LED mast head & steaming lights is almost exactly the same as a star. He explained, those lights tend to be weak and look exactly like stars from a few miles away. They are so small you do not notice them getting closer on a moonless night until you are right on top of them. This from a very experienced and careful professional seaman who also owns a lovely sail boat. He uses loads of LED's on the boat but not for his navigation lights. Next time in a dark anchorage look at the other boats mast head lights and you will see what he's talking about right away. Meggi once mistook one for Venus and was waiting for it to get a bit higher so she could practice with the sextant.

Freddyman 01-25-2011 05:58 AM

I can't see any reason why someone would choose LED for a steaming light. Since you are running the engine anyway, what's the advantage?

I do have an LED tri color and I doubt that it would be mistaken for a star. A ufo maybe, but not a star.

Maine Sail 01-25-2011 06:00 AM

Quote:

Originally Posted by HVVega (Post 690669)
I just wrote this in response to another thread but it struck me as so important I thought a new thread was called for.

I was having a beer with my friend who skippers about 50,000 tons of bulk carrier and he made a very interesting observation. Twice they have had to sheer off hard - not easy for a boat that size - because the color of "white" LED mast head & steaming lights is almost exactly the same as a star. He explained, those lights tend to be weak and look exactly like stars from a few miles away. They are so small you do not notice them getting closer on a moonless night until you are right on top of them. This from a very experienced and careful professional seaman who also owns a lovely sail boat. He uses loads of LED's on the boat but not for his navigation lights. Next time in a dark anchorage look at the other boats mast head lights and you will see what he's talking about right away. Meggi once mistook one for Venus and was waiting for it to get a bit higher so she could practice with the sextant.

One reason why you should not buy non USCG/ABYC A-16 certified nav lights. Certified nav lights MUST meet certain color spectrum standards or they don't get an approval.

That being said no real reason for an LED masthead/steaming light on many boats unless you want the longevity.....

BubbleheadMd 01-25-2011 07:47 AM

Actually, I can see the use of an LED steaming light. Not all smaller sailboats are equipped for engine charging, mine isn't and others who have older outboard without alternators may not be.

My outboard actually does have a 6 amp alternator, but I have to custom fabricate a longer charging cable because the one that came with the engine doesn't reach the battery bank. Right now, shorepower is my only charging method.

I understand that the USCG will certify a light based on it's brightness, arc of visibility, and color spectrum, but NOWHERE in the COLREGS can I find a reference to color spectrum beyond the words "white, yellow, red, green" etc. All it says, is that on a vessel of 12m or 29ft in length, you must display a white light, visible for 2 nm, in an arc of 22.5 degrees. It doesn't state an exact wavelength, nor does it even say that "only USCG approved lighting fixtures and lighting elements may be used". If it does, someone please provide a cite. Obviously, in a maritime law situation having all USCG approved lighting fixtures and elements provides an extra layer of legal protections, but I'm not seeing where it's mandated by law.

Further, the only time an anchor light or a steaming light should "look like a star" to a helmsman, is during a zero bearing rate (head-on) collision situation, where the light presents the illusion of not moving. In any other crossing scenario, the light will be moving across the helmsman's field of view rapidly enough to differentiate it from a star.

Look, this argument is as old as the hills. People have complained for years about how anchor and steaming lights look like streetlights and automobile lights when compared against the shoreline. There's always going to be an excuse as to why a skipper didn't see someone or suffered a collision.

Even if you legislate the exact frequency of light, lumens, fixture type and replacement elements, and certifying agency, for every class of vessel afloat, people are going complain that they "can't see" and use that as an excuse in a collision.

CapnBilll 01-25-2011 08:29 AM

An LED IS a point light source. Using an array of multiple LED's would prevent mistaking, and provide redundancy in case of failure.

BubbleheadMd 01-25-2011 08:39 AM

Agreed. The best ones (newer ones) come as an array inside of a single bulb or fixture with a heatsink built in.

Argyle38 01-25-2011 08:40 AM

This is the write up from Bebi Electronics on the subject. They reference Annex I Paragraph 9 of the COLREG's.

Bebi Electronics-What Our Marine RV & Off Grid LED Specifications Mean

I looked up the associated COLREG's and was suitably convinced in the safety and legality of the device so I went ahead and bought one of their sources for my anchor light and my stern light.

My steaming (masthead) light is incandescent since I'll always have the engine running, but when it blows, I very well may replace it with an LED for durability. I may consider a more "warm-white" type LED when that time comes, if I can get one that is bright enough.

I'm not at all worried about the color of the masthead or stern lights. If anyone mistakes my 30 LED anchor light with a star they have recently seen, they better be in the market for some frankincense.

Maine Sail 01-25-2011 08:43 AM

Quote:

Originally Posted by BubbleheadMd (Post 690726)

I understand that the USCG will certify a light based on it's brightness, arc of visibility, and color spectrum, but NOWHERE in the COLREGS can I find a reference to color spectrum beyond the words "white, yellow, red, green" etc.

The standards by which nav lights are built is published in the CFR (Code of Federal Regulations). You, as a used boat owner, are NOT required to have "certified" nav lights or install them UNLESS you are a boat builder or re-seller/broker/dealer. If you buy a new boat in the US it WILL have certified nav lights or the builder broke federal regulations.

If you are a builder you must use USCG/ABYC A-16 nav lights properly installed and placed for proper visibility. All USCG certified or ABYC A-16 lights will meet the minimum standards as set forth by the CFR. This is what labs like IMANNA use when testing nav lights to USCG/CFR nav light standards..

capecodda 01-25-2011 08:45 AM

Interesting discussion.

The Color Spec in the rules is located in International: Annex I, Part 7.

Maine Sail 01-25-2011 08:57 AM

Quote:

Originally Posted by Argyle38 (Post 690733)
This is the write up from Bebi Electronics on the subject. They reference Annex I Paragraph 9 of the COLREG's.

Bebi Electronics-What Our Marine RV & Off Grid LED Specifications Mean

An Bebi also says this:

"If you have insurance and you are involved in a collision at night, your claim may be dis-allowed if you have a non-OEM light bulb, whether it is an LED, incandescent, halogen, or fluorescent, in the fixture, regardless of the real reason for the collision."


With the cost of pre-made USCG certified fixtures coming way down in price I find it to be a false economy to use lights that are unknown as to whether they really meet the standards or not. The only way to know for sure is to have them tested by a lab like Imanna. If a manufacturer is not willing to put their money where their mouth is why should I pony up? By the way Bebi's statement that no aftermarket buls carry a USCG certification is a flat out mis-truth. There are four DR. LED bulbs that are USCG certified for use in certain Aquasignal Series 40 housings. I have the certification reports from Imanna stored on my hard drive. I still prefer a purpose built LED nav light as opposed to aftermarket bulbs, and I own two Dr. LED certified nav light combos. The Dr. LED bulbs have not proven to be very reliable and my Hella Series 32 LED's have been very reliable. When the next Dr. LED bulb fails the entire fixture will get replaced with a purpose built unit.

Having been involved in a night time death that involved a solid week of forensic navlight & navlight testimony, well before LED's, I am fairly confident that if my friends father had been using aftermarket LED's the drunk that killed him, by running him over, would have walked..

The defense lawyers left no stone unturned in their nav light investigation from voltage, to possible wiring faults to the flag possibly obstructing the stern light.... An LED that did not meet color, axis or otehr requirements would have made their job a slam dunk..


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