Collision Regulations : Navigation lights and their arc of visibility
by Nigel Richards 4 Mar 2018 11:43 UTC
Navigation lights ©
www.ecolregs.com
This month we are looking at some of the navigation lights and their arc of visibility. Even if you are sure of yourselves, it doesn’t hurt to have a reminder. So, lets start. Any vessel at night should be able to be seen by other vessels. Depending on the size of the vessel will depend on how it’s lit. Let’s look at lights for vessels of our general size; up to about 20 metres.
At night and poor visibility, we need to light up. Rule 23 says ‘A power driven vessel, underway, must show a steaming or mast head light forward, side lights and a stern light. The angle from which you can see these lights have a common denominator; 22.5 degrees abaft, or behind, the beam of the vessel. Therefore, from anywhere forward of that you will see the white high up high and either a red or green side light. If you are behind that 22.5 degrees from the beam, you should only see the stern light.
It is important to make every attempt to en-sure the angles of visibility are correct. It’s from these angles that everyone can make a true assessment of whether a risk of collision exists. Having a high-powered hand lamp is also a very important tool too; if a close quarter situation develops and you are unsure whether you are being seen, illuminating your sails or vessel's sides may assist the other vessels watchkeeper. Never shine the lamp toward the other vessel though, night vision once destroyed can take up to half an hour to restore.
When you are sailing, without mechanical assistance, Rule 25 stipulates you show port, starboard and stern light.
If your vessel is less than 20m, these can be combined into one tri-colour light at the top of the mast, most prefer this option for the reduced power load. Also, you can display an all-around red above an all-around green, as well as light sides and stern light. However, the all-around red and green must not be displayed in conjunction with a tri-colour light. Remember though, if your engine is driving the boat, you are deemed to be a power-driven vessel and must act as such by lights and responsibility.
During daylight that means you should also be displaying a black cone, apex or point down. This day mark is rarely seen but is a requirement under the rules.
This article has been provided by the courtesy of Island Cruising NZ.