January 19, 2010

Strobe lights at sea

MASTHEAD NAVIGATION LIGHTS have become taller and more complicated over the years. Now you can buy a triple-decker that shows, in layers, port, starboard, and stern running lights; an all-round white anchor light; and a white all-round strobe light.

The big question is this: if a strobe light is illegal up there, why should a sea-going yacht carry one?

Oh, yes, it’s illegal all right. Here’s Rule 36 of the International Regulations for the Prevention of Collisions at Sea:

Signals to attract attention
If necessary to attract the attention of another vessel any vessel may make light or sound signals that cannot be mistaken for any signal authorized elsewhere in these Rules, or may direct the beam of her searchlight in the direction of the danger, in such a way as not to embarrass any vessel. Any light to attract the attention of another vessel shall be such that it cannot be mistaken for any aid to navigation. For the purpose of this Rule the use of high intensity intermittent or revolving lights, such as strobe lights, shall be avoided.

Well, maybe it’s just sort of illegal. You’ll note that this rule talks about “avoiding” strobe lights, rather than specifically banning them outright. I take that to mean you shouldn’t do it all the time, but it’s OK to use a strobe in an emergency. In fact, in U.S. inland waters, the white strobe is a recognized Mayday signal, one that will summon help to you.

I read just the other day of a sailboat that came across a large fishing boat on a dark night and altered course to avoid it. Just as they changed course, the fishing boat also altered course – toward them. There was no response to the sailboat’s VHF radio calls, so they switched on their masthead strobe. That finally got the fishing boat’s attention, and they altered course again to miss the sailboat, admitting on VHF that they hadn’t noticed her until the strobe came on.

Legal or not, I, too, would use a strobe under those circumstances. If it frightens the fishing boat into thinking it’s about to go aground or run smack into a weather buoy, and gives the helmsman a heart attack (just a mild one) that’s too bad. They should keep a better watch.

I seem to remember the Pardeys advocating the use of portable strobe lights in one of their books. They fastened one to a long burgee stick and hauled it up to the masthead when they were hove to in heavy weather and both of them were down below.

Since then I have always carried a couple of those waterproof strobes that fasten around your arm with Velcro, so you can be seen at night if you fall overboard, and I wouldn’t hesitate to switch both of them on if I were being run down by a larger vessel.

Nothing attracts your attention like a bright strobe on a dark night. It is visible much farther away and more readily than a steady white or colored light, and when all is said and done it is the aim of all practical seamen, apart from those manning warships, to avoid collision and loss of life at sea. I can’t imagine any legal action being taken against a yacht that used a strobe to avoid being run down. So, OK, go ahead and buy one of those triple-deckers. It might help you sleep more easily at night.

Today’s Thought
Necessity knows no law.
— Mark Twain, The Innocents Abroad

Boaters’ Rules of Thumb #4
Alternator size: Lacking a multi-step regulator, the rule for long battery life is that you should limit the charging rate in amps to 10 percent of available amp-hours. With a modern multi-step regulator, you can charge at between 25 and 40 percent of the total amp-hours in your battery bank.

“I think your wife has had enough to drink.”
“Really? What makes you say that?”
“She’s all blurred around the edges already.”

1 comment:

BilB said...

In a discussion about being hove to at see the subject of visibility came up. The international signal for being stopped and not underway is the letter M which which is two slow flashes followed by a long pause. I believe it is legal to strobe this pattern and if it is used as well as the masthead anchor light it would add to visibility with the strobe pulses being more visible than the anchor light. This suggestion is for being visible in open waters, not anchorages.