Thoughts on Night Nav white lights

[SkinnyBoat]

Sorry Chris. You are not correct. 2 x 180 deg lights is equivalent to a single 360 deg light. There is no blind point at all, assuming they are fitted properly . However that’s a big assumption! Look at the maths… 180 x 2 equals 360. If the lights showed any more than 180 deg, then there would be 2 white lights showing from the beam. If they were 179 deg lights, then there would be a blind spot. Not to mention that the paddler would lose his or hers night vision from the forward light if it was more than 180deg. I fully accept that I would be crazy to sail between them, but my point is that there is an international standard on lights but many kayakers ignore them. Kayakers get away with this because they are few in number and generally paddle in shallow water… but it may just take one collision to attract official interest. I’m a sea kayaker, but have nearly hit sea kayakers at night in a large yacht because they do not show recognised or any lights. Legally, 2 single white lights means 2 boats under 7m. There is no opinion on this. If you wish to break the rules, then be aware of the risk.

The link you gave says: "Each light must be visible for 800m and through 180° – the boat must effectively have white lighting visible through 360". That is quite clear. I personally think the 2 white lights recommendation is rubbish as you cannot do this accurately on a kayak, this leaves a small mast with a 360 deg light or a helmet 360 deg light as the best option.

[Chris Bolton]

Personally, if I were paddling on the Thames and the PLA rules didn't require me to show two lights, I'd carry a single white light on a pole just behind me, as I would in international waters or where there are no local rules.

But the PLA rules ( and they are rules, not recommendations) do require two lights, and my point was that it's invalid to quote the poster who shows two white lights in PLA waters as an example of not following the rules, because it's following the rules exactly.

I've never suggested not following the rules, but I recognise that, as stated in the COLREGS, local rules can vary so it's important to follow the right ones.

My following point was trying to understand why the PLA require two lights and what their intention is regarding 180º. Practically, setting up lights with an accurate cut-off would be difficult, but the basic question remains; do the PLA expect the lights to be visible from abeam or not?

Two exactly 180º lights are only equivalent to one 360º if there is no gap between them. If they are not visible from abeam, then the boat is unlit from that angle, so fails to meet the 360º requirement. So they must be visible from abeam, and in that case there will be two lights visible. In that situation, I would expect any other vessel to be aware of the local rules and assume there's a kayak between the lights. If the other vessel is clearly ahead or astern of abeam, they'll only see one, but hopefully not pass too close to it.

If you disagree, please tell me what you disagree with and how you would interpret the PLA rule as written (not how you think it should be). Just saying I'm wrong or I'm writing rowlocks isn't helpful.

[SkinnyBoat]

It’s a code. Not rules. https://www.pla.co.uk/assets/tidewaycodedigital.pdf

As far as kayak lights go it starts: ‘ As far as possible, the following lights should be firmly fixed to the boat .“ I am glad to see that you are no longer promoting your 220 deg white lights that would destroy the night vision of the paddler and would show 2 white light s from the beam. Again, 2 180 deg lights properly fitted will have no blind point from the beam. A 220deg white light on the bow will blind the paddler. I’ve done 1000s of miles at night in various boats, and these things are important.

[Chris Bolton]

It’s a code. Not rules.

Apologies, you're correct.

I am glad to see that you are no longer promoting your 220 deg white lights

I wasn't promoting them, I was (as explained at length) trying to understand the logic.

2 180 deg lights properly fitted will have no blind point from the beam

If there is no blind point, they must be visible. So there will be two lights visible. But it's pointless to discuss it further.

[SkinnyBoat]

"If there is no blind point, they must be visible. So there will be two lights visible. But it's pointless to discuss it further."

That is a complete impossibility. 2 x 180 deg lights are the same practically as a single 360 deg light. Total rowlocks above in my opinion. Happy to see that you agree with the fact that the the PLA code are not rules.

Let’s enjoy our time on the water. I am sure we all accept that lights on a kayak are difficult to adopt to international standards.

[Sean_soup]

That is a complete impossibility. 2 x 180 deg lights are the same practically as a single 360 deg light. Total rowlocks above in my opinion.

Are you as unbearably condescending as this in real life? You're coming out with some right old bollocks yourself. (Using the word 'rowlocks' as a euphemism does nothing to make that seem more polite btw.)

We're talking here about cheap navigation lights, not optical laboratory equipment and frikkin laser beams operating in a vacuum: there is no such thing as a perfectly 180° light. They're only 180° to within manufacturing tolerances, and beams have fuzzy edges even before the light starts reflecting and refracting about the place.

But assuming theoretically perfect 180°lights perfectly aligned, they are practically the same as a single 360° light if they are close together because you can't see either if you are in between them. Whether 5m or so separation is close together for a given observer depends how far away the observer is. The observer would fairly self evidently have to be far enough away that the difference in the bearing from their position to the one light and the other is negligible - at which point the observer is not going to be thinking "look at those two lights over there, I'm going to sail in between them".

I mention that because it's what you said above - that if you saw two lights, at the bow and stern of a kayak, you might perceive them as two separate craft <7m and sail between them. The two lights are 5m apart tops, so even if your assumption that you're looking at two separate craft were correct there would still be no gap between them that you can fit through, and if you try you'll collide with one of those little craft or both. If a craft with a light on it could be anything up to 7m, aiming to pass within 2.5m of that light is self-evidently a bad idea.

Under the circumstances, a kayaker close to the big boat you're in charge of might be better off with no lights at all. Sure you might run into them accidentally, but at least they'd be making it more difficult for you to do it on purpose!

[mrcharly]

Let's have a bit of uncommon sense here.....

No-one, at night, is going to attempt to navigate through a gap of 4 to 7 metres.
The length of time which a boat with 2 180 degree lights, bow and stern, would spend at exactly 90 degrees to an observers line of sight will be negligible, so is irrelevant.
I don't know of any lights with a 180 degree cut off which could be mounted on a kayak and are not 12v powered from an on-board battery.
I don't know of any reliable way to mount such lights without a bit of non-reversable work being done at bow and stern.

Visability is key - light mounted bow and stern on a kayak will be below the height of any chop / swell so, for the most part will be invisible.
In busy waters at night I doubt if anyone is going to complain about a kayaker who will be complying with colregs by showing an all round white light, possibly on their head.
And if they do complain - I wouldn't want to paddling there anyway.

The highlighted bit isn't correct for one type interaction on rivers - rowing skiffs and kayaks.

I used to live in Cambridge and train with the local kayak club on the Cam. Unfortunately, that meant sharing the space with rowing 8s.

The local regs require front white and rear red lights, so that it is possible to tell direction of travel, and get an idea of front-rear of boat. Especially important when the boat is a rowing 8, turning on a narrow river.

Without the lights, there would have been many collisions.

[pathbrae]

Let's have a bit of uncommon sense here.....

No-one, at night, is going to attempt to navigate through a gap of 4 to 7 metres.
The length of time which a boat with 2 180 degree lights, bow and stern, would spend at exactly 90 degrees to an observers line of sight will be negligible, so is irrelevant.
I don't know of any lights with a 180 degree cut off which could be mounted on a kayak and are not 12v powered from an on-board battery.
I don't know of any reliable way to mount such lights without a bit of non-reversable work being done at bow and stern.

Visability is key - light mounted bow and stern on a kayak will be below the height of any chop / swell so, for the most part will be invisible.
In busy waters at night I doubt if anyone is going to complain about a kayaker who will be complying with colregs by showing an all round white light, possibly on their head.
And if they do complain - I wouldn't want to paddling there anyway.

The highlighted bit isn't correct for one type interaction on rivers - rowing skiffs and kayaks.

I used to live in Cambridge and train with the local kayak club on the Cam. Unfortunately, that meant sharing the space with rowing 8s.

The local regs require front white and rear red lights, so that it is possible to tell direction of travel, and get an idea of front-rear of boat. Especially important when the boat is a rowing 8, turning on a narrow river.

Without the lights, there would have been many collisions.

Perhaps - but straying a long way from the OP.
What length is a rowing 8? Long enough to be well outside the COLREGS definition of a "small unpowered vessel" I suspect.
Also, we wouldnt be on tidal water in Cambridge So a completely different scenario to paddling on the tideway.

[mrcharly]

Although my experience is on the non-tidal part of the Cam, I do believe that rowing skiffs are used on the Thames.

8's take ages to turn, and are 19.9m long.

[twopigs]

Just to muddy the water ..... I would have thought some consideration should be given to the intensity of these lights - on dark sections a diffused light as suggested might be seen but on sections with a lot of lights on the banks .......

[mrcharly]

Wanted to update this.

Since my last query I purchased and mounted a kayalite.

Mounting:
My boat is a nelo 510, rotomoulded plastic. No through fittings that I could use.
I bought a D-ring patch (intended for gluing to RIBs) and some superglue that was for polyprop. The glue had some prep solvent that cleaned the plastic. Superglue on patch and it is solid. No sign of lifting in a year and half.

Light in use:
I put the light on the boat when walking it down to the shore (a mostly unlit rural road). Gives me some comfort knowing that cars will see it.

Out on the water, there is a surprising amount of light. If it were in front of me, or if I were with other paddlers, it would be dazzling.
As a solo paddler, I like knowing that I show up, boats are likely to see me. Also, in the event of a catastrophe, my boat would be easier to find.

Haven't kept track of hours of use on one set of batteries. It's probably had about 6-8hours so far.