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Old 06-11-2012, 07:18   #61
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Re: Never really wanted Radar or AIS until this Moment

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Really dense fogs can happen really fast and be incredibly localized here (PNW) I have known people that have made it through tight passages in the San Juan Islands using radar. GPS had an accuracy to 5-10meters at that time and 2meters could put you on the rocks, you couldn't see more than a boat length away so radar was the only way to navigate.
Port T is at or near the northern end of a convergence zone in the lee of the Olympic peninsula. Somewhere around Bellingham is to the extreme south of that zone. Features include dense fog which is highly localized, just as you say. But that the formation is known, one should not be caught unaware. One suggestion is to note winds at the surface and winds aloft to correlate wind speed to incidence of fog formation.
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Old 06-11-2012, 07:26   #62
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Re: Never really wanted Radar or AIS until this Moment

I have found the trouble with the recreational power boats in fog is that they have their radars on (you can see the radome turning) when they appear about 100 feet abeam of you at 3/4 throttle on a collision course. I can only assume that the boat driver doesn't really know how to use a radar, but since he has one, he assumes he can drive like it's a sunny, clear day. If nothing's immediately in front of him on the radar, he assumes all is clear. They don't seem to have any concept of relative bearings, how to recognize a collision course, etc.

I don't know what to do about this, except go slow and LOOK OUT! There are a lot of radar-assisted collisions in the fog.
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Old 06-11-2012, 07:49   #63
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Re: Never really wanted Radar or AIS until this Moment

[QUOTE=Richard5;1077828]
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My contention is being caught unaware. Not once have I been in a fog because I was unaware of it's formation.
Where do you sail, in terms of home waters?
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Old 06-11-2012, 09:10   #64
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Re: Never really wanted Radar or AIS until this Moment

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Port T is at or near the northern end of a convergence zone in the lee of the Olympic peninsula. Somewhere around Bellingham is to the extreme south of that zone. Features include dense fog which is highly localized, just as you say. But that the formation is known, one should not be caught unaware. One suggestion is to note winds at the surface and winds aloft to correlate wind speed to incidence of fog formation.
Actually one should not be caught un aware and ill equipped....the friend I was talking about was not caught unaware, he knew the fog was there and also knew how to work his radar which was integrated with his charts.
The sky can be crystal clear and sunny and just around the point on the other side of Admiralty Inlet it can be pea soup. I get a kick out of standing in the sun, looking out onto the water at a fog bank and seeing just the bridge of a freighter up in the sun above the fog.
Radar can helpful in any conditions that reduce viability, fog rain, dark (moonless overcast night)etc.
AIS provides a tremendous amount of information about the "big boys" around you...though not all places in the world (or where I plan on cruising) require AIS transponders.
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Old 06-11-2012, 11:00   #65
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Re: Never really wanted Radar or AIS until this Moment

I've been in that sort of fog where all about is dense, but you can see the sun and patches of blue sky overhead. That's tough on the eyes. It's also about the closest I've come to running down a fishing boat that was blissfully bobbing with no signals well offshore.
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Old 06-11-2012, 11:57   #66
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Re: Never really wanted Radar or AIS until this Moment

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Back in my Santana 22 days, when the only nav instruments I had onboard were a compass, a knotlog and a watch, I once anchored 100 yards from the entrance to Stillwater Cove because I couldn't find it. I kept sounding my whistle every two minutes until the harbormaster came out in his launch to lead me in. That's when I bought my first GPS.

I bought my first radar after having spent the night off the Big Sur coast in fog so dense I couldn't see my bow pulpit. Those are the times you make holy vows to become better equipped. Thank goodness so many of us survive them. Not everyone is that fortunate.
We inadvertently anchored a bit too close to shore at Stillwater Cove and hit rock with our keel after being lifted up and down from the swell. We got out of there FAST. The harbormaster at Stillwater came over to us after having seen our difficulties and offered us a mooring for our overnight stay. In fact, he took our line and ran it to the mooring ball. It might be a private enclave, but they uphold the best traditions of maritime assistance (as you experienced as well).

We bought our AIS when, after returning from a long sail down from the Delta, as we approached the central bay we heard on vessel traffic (we always monitor this on the Bay) that there was BIG ship traffic coming down from the north behind us, from the south towards us, from the west to Oakland, and from Oakland west to sea.

My biggest problem with AIS - the large number of targets that show up on SF Bay - even more cluttered with recreational vessels adding the transmit function.

My most fun with AIS - seeing the S/V Maltese Falcon across the Bay, finding them on AIS, and seeing their destination listed as "Day Sail".

Fair winds,
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Old 06-11-2012, 13:16   #67
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Re: Never really wanted Radar or AIS until this Moment

Those who have spent much time sailing in congested coastal waters where fog is common know that a VHF radio and a good, loud horn are essential pieces of safety equipment. (A noise making device is required on all boats, regardless of size or method of propulsion.)

The vessel in this situation should have been:

1) sounding its horn at intervals of not more than every two minutes (as opposed to the 3-5-minute intervals stated in the original post). If it was sailing and did not have its engine on, it should have sounded one long (4-6 sec) blast followed by two short blasts (<1 sec) every 2 minutes. If it had its engine on (regardless of whether its sails were up), it should have sounded one long blast every 2 minutes;

2) making "securite" calls periodically on VHF ch. 16 to notify other vessels of its current location, speed, heading, and destination; and

3) monitoring channel 16 for securite calls made by other vessels.


Radar and AIS are great tools. But they aren't foolproof. Use all of the tools that you have at your disposal but TRUST NONE OF THEM. The best way to avoid a collision at sea is to know and follow the Navigation Rules. If everyone followed the Rules, there wouldn't be any need for AIS.


The following are quotes from the Navigation Rules:

"Rule 35 - Sound Signals in Restricted Visibility

In or near an area of restricted visibility, whether by day or night the signals prescribed in this Rule shall be used as follows:

(a) A power-driven vessel making way through the water shall sound at intervals of not more than 2 minutes one prolonged blast." (This includes sailboats under power...whether or not the sails are being used.)

"(b) A power-driven vessel underway but stopped and making no way through the water shall sound at intervals of no more than 2 minutes two prolonged blasts in succession with an interval of about 2 seconds between them." (i.e., A boat drifting with its engine on but not in gear.)

"(c) A vessel not under command, a vessel restricted in her ability to maneuver whether underway or at anchor, a vessel constrained by her draft, a sailing vessel, a vessel engaged in fishing whether underway or at anchor and a vessel engaged in towing or pushing another vessel shall, instead of the signals prescribed in paragraph (a) or (b) of this Rule, sound at intervals of not more than 2 minutes three blasts in succession, namely one prolonged followed by two short blasts." (Does not include sailboats that are motor sailing.)
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Old 06-11-2012, 13:27   #68
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Guess this doesn't aply to cargo freighters or cruise ships
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Old 06-11-2012, 13:42   #69
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Re: Never really wanted Radar or AIS until this Moment

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A bigger concern is careless fisherman heading off at a high rate of speed to get to here early morning spots, not seeing the white sailboat.....
Or maybe a French high speed ferry not bothering with fog signals and chit-chatting rather than paying attention to their radar.

Condor ferry hits French boat – fisherman killed | News | Pbo

http://www.beamer-france.org/BanqueDocument/pdf_289.pdf See second half of this document for english translation, unless you prefer the french original.
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Old 06-11-2012, 13:48   #70
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Re: Never really wanted Radar or AIS until this Moment

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The issue here is we were already 10+ miles from land and. In an area of known for alot of traffic both large ships and small fishing recreational boaters when the conditions deteriorated. Coast guard typically issues a low vis safety warning etc.they didn't start doing this until the fog had been there for several hours. The fog also didn't lift until after 10 am. Someone mentioned put down the android well if we had wed or not known were close to a cruise ship and a large freighter. Neither of which issued any type of fog warning. It seems people are quick to assume we had to choice to be in fog or not. Or even that stopping would have been any safer. At least we knew where the big boys were. Maybe I should have changed the title to " Glad we had marine traffic on a DROID, even Radar wouldn't have saved us from stupid rec powerboaters "
Sorry if my post came over as being critical. I believe radar to be an essential safety tool for cruising and the point I was making was when considering tools radar should not come after AIS.
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Old 06-11-2012, 14:08   #71
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Re: Never really wanted Radar or AIS until this Moment

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Guess this doesn't aply to cargo freighters or cruise ships
I also didn't mean to come off as critical. Just trying to suggest what you could have done differently in that particular situation and educate the readers of this forum.
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Old 06-11-2012, 14:43   #72
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Re: Never really wanted Radar or AIS until this Moment

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Back in my Santana 22 days, when the only nav instruments I had onboard were a compass, a knotlog and a watch, I once anchored 100 yards from the entrance to Stillwater Cove because I couldn't find it. I kept sounding my whistle every two minutes until the harbormaster came out in his launch to lead me in. That's when I bought my first GPS.

I bought my first radar after having spent the night off the Big Sur coast in fog so dense I couldn't see my bow pulpit. Those are the times you make holy vows to become better equipped. Thank goodness so many of us survive them. Not everyone is that fortunate.
LOL. I hear ya! The darkest night I ever saw was 3 AM in Block Island Sound when a fog rolled in. I used radar to find the buoy I lost in the fog and was able to get close enough to verify it. This was the pre GPS days. Recently did my first cruise with my AIS transponder through New York Harbor and found it to be one of the best things to have on board. I was not surprised once by any of the Tugs and barges coming up behind me. Only a fellow sailboat or two without AIS. Though AIS will not save you from the powerboater doing 30 knots it will save you from those BIG boys and use a lot less power than radar Plus it provides a lot more information so you don't have to guess what that target coming up behind you is. It is a great addition for safe passage making IMO.
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Old 06-11-2012, 15:15   #73
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Re: Never really wanted Radar or AIS until this Moment

That Condor ferry was going 40 knots, he can't hear fog signals over the engines and - as we saw in the report from the Ouzo collision - yacht radar reflectors are just about worthless. But he does have AIS -

Live Ships Map - AIS - Vessel Traffic and Positions

I had questions about AIS too -- until I installed a transponder. Now I consider it far more important to my safety in crowded waters than my radar, horn, and radar reflector.

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Old 06-11-2012, 15:42   #74
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Re: Never really wanted Radar or AIS until this Moment

All electronics are but tools which when combined with other navigational tools make for a well equipped "navigational tool box" (of which one og the most important ingredients if the ability to use them)
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Old 06-11-2012, 15:52   #75
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Re: Never really wanted Radar or AIS until this Moment

Ask your crew how THEY feel about you sailing them in the fog without Radar or AIS...

....."Oh, and by the way crew, today we will be sailing in dense fog, across the shipping lanes, and among fast moving ships and many boats as well...But don't worry crew, we won't see them, and they can't see us!"
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