Nav lights at night

[Anonymous]

One of the things that I notice getting worse, not better, is the number of yachts not showing any lights - or maybe they turn them on suddenly, when they have seen you. I have noticed this in the Channel and the Med.

Have others noticed the same thing?

Another problem that is just starting is washed-out reds and greens. The colours are so un-saturated that from a distance it is impossible to distinguish between green and white or even red and green. By 'distance' I mean only a couple of miles as that's usually the max range. Often those vessels don't show on the radar, either making them a hazard to themselves and everyone else. I suspect that the colour problem is down to certain LEDs.

Have others noticed the same thing?

I would hope that in time good low-power LEDs that meet the requirements of Appendix 1 of the Colregs (and are as green and red as they should be) will become commonplace, and everyone will leave their lights on, but for now, I perceive this to be one of the greatest general safety issues facing mariners at night.

 

[RestlessL]

Perhaps they need the power to run their laptop so it will switch them on automatically when a dangerous AIS target is detected /forums/images/graemlins/tongue.gif

 

[awol]

There is no "Appendix 1" to the Colregs. "Annex 1", Section 7 defines the limits of the colour co-ordinates for navigation lights and Rule 22 defines the luminance in terms of distance of visibility - a mere 1 nautical mile for the sidelights of a vessel <12m - with Annex 1 Section 8 defining the objective quantities that give the ranges.

It is possible that the absence of light, followed by sudden appearance, is caused by distance or waves; the brightness, if you can see tham at 2 miles (and they are <12m), already exceeds the requirements; and the colour should be correct for lights meeting the specification.

You may feel that the Colregs are inadequate in this respect but that, I feel, is a different topic.

 

[Anonymous]

It is "Annex 1" and not "Appendix 1", as you say. The colour and intensity details are all there and I reproduce it below. It should be incumbent on suppliers of nav lamps to ensure that their product comply with these regulations, surely?

<span style="color:blue"> 7. Colour specification of lights
The chromaticity of all navigation lights shall conform to the following standards, which lie within the
boundaries of the area of the diagram specified for each colour by the International Commission on
Illumination (CIE).
The boundaries of the area for each colour are given by indicating the corner co-ordinates, which are
as follows:
(i) White
x 0.525 0.525 0.452 0.310 0.310 0.443
y 0.382 0.440 0.440 0.348 0.283 0.382
29
(ii) Green
x 0.028 0.009 0.300 0.203
y 0.385 0.723 0.511 0.356
(iii) Red
x 0.680 0.660 0.735 0.721
y 0.320 0.320 0.265 0.259
(iv) Yellow
x 0.612 0.618 0.575 0.575
y 0.382 0.382 0.425 0.406

8. Intensity of lights
(a) The minimum luminous intensity of lights shall be calculated by using
I = 3.43 x 106 x T x D2 x K–D
where I is luminous intensity in candelas under service conditions,
T is threshold factor 2 x 10-7 lux,
D is range of visibility (luminous range) of the light in nautical miles,
K is atmospheric transmissivity.
For prescribed lights the value of K shall be 0.8, corresponding to a meteorological visibility of
approximately 13 nautical miles.
(b) A selection of figures derived from the formula is given in the following table:
Range of visibility Luminous intensity of
(luminous range) of light in candelas for
light in nautical K=0.8
miles
D I
1 0.9
2 4.3
3 12
4 27
5 52
6 94
Note: The maximum luminous intensity of navigation lights should be limited to avoid undue glare.
This shall not be achieved by a variable control of the luminous intensity.
30
</span>

The effect you suggest is not what I am talking about. I am talking about seeing an outline of a yacht at sea with no lights on, then the lights suddenly coming on when a larger vessel comes into sight (quite typical).

I don't have a problem with actual requirements of the colregs if only people would actually turn their lights on after dark and ensure that the colour of their lights looks, at a good distance, the same as 'ordinary' tungsten lights. Many of them look washed-out even close up. One person told me that he preferred his new LED lights - much nicer colours than the traditional ones /forums/images/graemlins/shocked.gif /forums/images/graemlins/confused.gif

 

[awol]

The bit you are missing is Rule 22 which defines the "visibility" and gives the "ranges" for different classification of vessels. 1nm is the sidelight requirement for vessels <12m. The technobabble you quoted just gives the method for determining this.

Visual acuity and colour perception varies between individuals and is known to deteriorate with age (and allegedly with onanism /forums/images/graemlins/tongue.gif). The lights of which you complain almost certainly conformed with the regulations when they were purchased, and I would be surprised if they had deteriorated outside the limits.

As for running without lights - I would have thought that LED users were much less likely to be guilty than incandescent bulb users - after all they have expended quite a large sum, usually for a replacement, for the main advantage of low current draw.

I admit to occasionally running without lights - my excuse being the absence of a masthead tricolour and the night-vision destroying reflections off sea and spray from my pulpit mounted bicolour. Most common times are in areas of pot/net markers and when a distant light "may" have been sighted.

 

[Anonymous]

I left out the non-technical stuff as that is well-known to everyone (hopefully!?). What seems to be less well known is that the rules don't just require the lights to be 'visible' but they define how to determine that visibility. They also define the colour. This means that any nav light manufacturer can test (in-house or using a test laboratory) his lamps to a simple specification. There is no need for any nav lights to be made that do not meet the Regulations but no doubt it is much cheaper to make LED nav lights that don't! I know of more than one LED manufacturer who claims to meet the requirements so it should not be difficult to source them.

If you look at vessels lights at night - have a look on a busy river or channel with dozens of boats coming and going - 90% or more will have colours that are identical - whether they are little inflatables, yachts, pilot cutters or large ships, the colours are the same. Now take a look at the colour of some nav lights known to be LEDs and you will see that some of them are very washed-out. The colour is different to ordinary nav lights. Surely, if you sail at night you have already noticed this and wondered why? It is not a problem close by but it is a problem farther away. The point is not whether you 'like' the new colour or think it is 'better' - though I certainly don't - the point is that the colours clearly don't match traditional nav lights.

I would hope that LED light owners would run their lights at night. I would hope that everyone runs with nav lights at night with no exceptions. The whole point of lights is to allow others to see you and if you don't show them or if you keep turning them off you will confuse others. My suggestion is that if your lighting arrangement causes you problems then you need to change the arrangement. If, as you suggest, onanism might be the problem then you know what to do about that /forums/images/graemlins/wink.gif I have never had that problem myself, or switched my lights off at night, for any reason at all.