When to Start Blowing the Fog Horn

[markpierce]

When should one start blowing one's fog horn? In my mind, it should be when the level of visibility is less than the range of one's fog horn. So, big ships should start blowing when visibility drops to two miles, and the smallest vessels at one-half mile. What do you all say?

[nigel1]

On my big ship, usually at about less than 1 mile, but it all depends on other circumstances.
On my own boat, not yet (thankfully) been in a situation where where I have needed to, I've got one of those hailer type horns with the auto signal.

As an aside, but to do with fog horns, years ago I was a ship of some 400m in length, with a fog horn fwd and aft. The 3rd mate advised the lecky that the fwd horn was not working.
Lecky climbs foremast, and asks 3rd mate on the bridge to press the tit. As you can guess, nothing wrong with the horn, its directed forward, so not heard from the bridge. Took about a week for the lecky to recover his hearing

[wolfaroo]

I think 0.5nm is the maximum range of a horn on a vessel <20m in ideal conditions, but with background noise such as engines etc. in anything other than ideal conditions, it is doubtful another vessel 0.5nm away would hear you clearly.

If it is a bigger ship, then you will definitely hear them before they hear you so you don't really need to start sounding until after you hear them if vis around 0.5nm.

At 0.5nm vis you have plenty of space to manouver and will probably see another <20m vessel before you hear them. Therefore, except when you can hear another horn, it probably isn't worth sounding yours regularly until vis <0.25nm.

IMHO.

[sailorboy1]

I think a lot depend so on where you are when the fog rolls in and what type of boat is expected to be around.

If you blow you horm every 2 minutes like you are suppose to and only sailboats are around, which may be doing about 5 knots, that's 0.67 km if both boats are heading toward each other. So you are on each other about the same time one hears the horn.

Of course if in an area with power boats, freighter, ferrys, etc. they probably don't even hear your canned horn at all till they run over you.

On my most recent 20 mile trip in the fog I was the only boat who sounded their horn (at least I never heard any other which is almost the same thing). This included when I saw something on radar and sounded the horn and had a close call but never got a horn reply.

So to answer the question; as soon as the fog hits and you can not see far enough around to be able to make a course change in time to avoid the collision that comes out of the fog.

I now know that to be safe I really should have at least 4 can of air horns on the boat! But of course I don't.

[MarkJ]

Originally Posted by markpierce

When should one start blowing one's fog horn?

Now.

It'd stir up this bay

[S/V Illusion]

When you can't see well. Usually coincides with the time you start thinking about it.

[S/V Alchemy]

When you feel waving the white cane at the bow is becoming ineffective.

[capn_billl]

Anytime it's foggy?? Seriously if you can see the fog it's probably time to sound the horn. Don't wait until you can't see the hand in front of your face.

[Captain Bill]

I really wonder what good fog horns do in the age of power boats. I was once off of St. Augustine in fog with only about 100 ft visability. I decided to lay off the inlet until the sun came up and the fog lifted before going in the inlet. All the time I'm dutifully blowing my fog horn every two minutes. As it started to get light, sports fishermen started coming out of the inlet in high powered boats at very high speed. I heard no fog horns from any of them. With the sound of their engines I'm pretty sure they never heard mine. One guy came blasting out of the fog despite me blowing the trumpet horns and missed me by only about 20 ft. I'm guessing he was doing over 30 knots and I don't think he could have heard anything over the sound of his 3 200+ Hp outboards. I seriously doubt the guy at the helm ever saw me. At least he never turned his head to look in my direction. Several other boats passed by just at the edge of visibility, all at normal power boat cruising speed.

[Arch Stanton]

I was out in some nasty fog crossing the Strait of Juan de Fuca and came upon something I never would have expected - a kayaker. Missed him by about 30 feet. I was keeping a very close watch that day but some things you just can't see till you're on top of them.

Also crossed close behind this guy that day:

[Dsanduril]

Was in Long Beach harbor one day. Lookout on the bow, because the extra 30' helped. Going dead slow, trying to find the Los Alamitos breakwater (knew about where it was). Long before GPS. 20' runabout comes roaring by at full speed, just about exactly the same time as the bowman calls out the breakwater. Runabout makes a skidding turn, but going too fast. Piles up on the breakwater, ejects two people. It was a mess, but both lived to talk about it. Never could have heard our foghorn over his engine, and going too fast for it to make a difference if he did. Had he been 15' to port would have been right up our transom.

[boatman61]

When your butt muscles cant handle the stress,,,,,