Being seen ...

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For anyone who hasn't already read it, the MAIB report of the sinking of the Ouzo can be found at:
http://www.rya.org.uk/NR/rdonlyres/60475AB0-CB12-45B9-BDCC-1E80129524D3/0/MAIBReport.pdf

It makes for dismal reading indeed: apart from the actual tragedy itself, it appears that masthead tricolours are considered inadequate when heeled more than 5 degrees or so, and yacht-sized radar reflectors in general appear to be largely ineffective devices - again, especially when heeled. This finding is also a conclusion reached by: http://www.ussailing.org/safety/Studies/radar_reflector_test.htm

I'm left wondering just how many yachtsmen and women are floating around with a false sense of confidence: under the mistaken notion that they can be easily seen by everybody else, including heavies carrying multiple radars and with lookouts on station ?
Colin
 

CPD

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[ QUOTE ]
I'm left wondering just how many yachtsmen and women are floating around with a false sense of confidence: under the mistaken notion that they can be easily seen by everybody else, including heavies carrying multiple radars and with lookouts on station ?
Colin

[/ QUOTE ]

I dont have a false sense of confidence. I have a very real sense of survival. I keep out of the way, colregs or no colregs.
 
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What's happened to all the older threads ?

I seem to remember we've discussed visibility at sea before. Wasn't there a thread on the use of masthead strobes ? I'm pretty sure it was in that thread that I suggested using a BIG all-round white in preference to masthead tri-colours.

My reason for posting that then, was that a couple of years back I followed another yacht into Oostende in the wee small hours as a bad blow was developing into something worse. A dirty night, and as the yacht ahead of me rolled, it kept becoming completely invisible, and that was at a distance of about half a mile. I knew approximately where it was, but someone visually scanning ahead of a fast-moving ship would probably never have seen it. When we tied up, I mentioned this to the skipper of the other (expensive) yacht, but he was adamant that his lighting complied fully with the regs etc. I might as well have kept me mouth shut.

Wasn't there also a thread on the use of hydrophones, where 7.5 minutes was considered by somebody as a long time when a ship closes with your vessel at 4 knots ? (not sure where the 4 knots came from)

The Pride of Bilbao's watch had scanned their radar just 3 minutes (1 mile) before the alledged incident with the Ouzo - and reported seeing *nothing* on their screens. Until the very last moment, there was also *nothing* seen by the visual lookout.

3 guys, all experienced, and probably all on deck at the time - and they STILL got run down. The Bilbao would have been highly visible with all it's deck and cabin lights on. It doesn't make any sense.

Seems to me that there are people using stuff at sea - which simply doesn't "do what it says on the tin", so to speak.

Colin
 

BrendanS

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They are still there. At the Jester forum page, scroll down towards bottom. Click on the 'Show' drop down box, and change from 3 months to all dates, and click on the change button. This will show threads from beyond 3 months
 
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[ QUOTE ]
They are still there. At the Jester forum page, scroll down towards bottom. Click on the 'Show' drop down box, and change from 3 months to all dates, and click on the change button. This will show threads from beyond 3 months

[/ QUOTE ]

Ennit good when someone knows what they're doing ...

Thanks
Colin
 

lumphammer

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[ QUOTE ]


3 guys, all experienced, and probably all on deck at the time - and they STILL got run down. The Bilbao would have been highly visible with all it's deck and cabin lights on. It doesn't make any sense.



[/ QUOTE ]

I suspect that had Bibao been going in a straight line then the Ouzo tragedy wouldn't have happened, I think that since Bilbao didn't see them it turned into them, and Ouzo just wasn't fast enough to get out of the way.

This is the only problem with my philosophy of 'keep out of the way of the big stuff' it only works if they keep going on a steady course. Still, mid-atlantic hopefully 'big stuff' will all be going in straight lines
 
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I think that's a fair conclusion to draw - but as you say "since Bilbao didn't see them ... " - and that for me is the key fact: that they simply were not visible at night to a ship equipped with radar and with lookouts on station.

On the high seas ? Well, lookouts do get bored and fall asleep, and of course you have to get to the high seas in the first place - and this will inevitably mean passing through shipping lanes.

So how can we make small boats more visible ? I've been wondering about the practicalities of lining the inside of the boat above the water-line with aluminium foil. Would that help ? I suspect it would be a heeling issue again.

I dunno - billions of dollars spent developing stealth technology - and we want to do the reverse !

Colin
(who's just bought a 3 million candle-power spotlight ...)
 

lyina

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Being Seen

What about a chaff type flare for emergencies, could be used from a life-raft as well to attract a rescue !?
 

PacketRat

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Re: Being Seen

I've heard the crumpled bako foil idea before. I'm going to screw up a few rolls and put it aft and in the forepeak simply because I can't think of any reason not to.
It would be nice to know if anyone's tested the idea.
Robin.
 

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There was a sailing mag test a few years ago with 2 boats - one who had crumpled al foil stuffed into nooks and crannies everywhere, and another whose owner had carefully lined his cabin and topsides with al foil before relining it.

The first boat produced a slightly better return to an identical boat without foil, while the second became almost invisible - the smooth foil was reflecting the return away from the transceiver. IIRC there was also the suspicion that the foil was masking any reflection from the engine block, which is usually the strongest reflecting component .
 

Gargleblaster

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[ QUOTE ]
On the high seas ?

[/ QUOTE ]
This is what worries me. In a standard Atlantic swell [1 to 2 metres] I've been told by a Dutch ship that they had been watching me for an hour on radar as they came up behind me. However with the clutter associated with big seas and or rain, I wonder how well I could be seen. In big seas I have been within half a mile of big container ships and bulk carriers which disappear from visibility in the troughs and while a bridge is much higher than my cockpit I must disappear down the troughs as well. And my mast is only 12 metres above the water and most ships stand much taller than that. I have noticed in heavy weather you see a lot fewer ships in the Atlantic. I manage to convince myself that this is because they are trying to avoid teh low that I am in however it may be that when I am looking they have disappeared down a trough.
 

andlauer

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Bonjour
In 23 days crossing back the Atlantic I met very few boats betwenn 5 and 10.
In NW Atlantic the fog is such that you can't have an efficient visual watch.
hopefully the boats are not aiming at you so the risk of a collisison is as small as with a container...
An efficient mean, for the boats (not for the containers), is the AIS.
Eric
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Jake

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Hi John (Glayva)

You're absolutely right. I have made two crossings of the Channel on the bridge of a ferry - one a 50 knot fast cat, and the other a conventional ship.

Spotting boats electronically is a nightmare in anything over a force 4-5.
Visually, at night, and in poor weather, it's not much better.

The skipper told me that boats ( especially small motorboats) vanish into the seaclutter on radar, and only sharp lookouts can spot the often weak masthead lights of yachts. On the fast-cat, these lookouts (with x8 bino's) were permanently posted on each bridge wing, despite two powerful radars working in two different wave bands.

My own defence is in three areas - visual ( day) - lots of bright paint - including a bright flourescent 2m section at the top of the mast, and a huge radar reflector also painted 'rescue' orange. The divers say that fluorescent yellow is better still, so considering that for my top sail panel.

Visual (night) - powerful, low-draw navlights set high - one set on the A frame aft, another combo on the mast. (Not used together, of course!)

Electronic. - Mother of all radar reflectors, set high astern. Anything creeping up behind should get a return - not always the case from a refelector mounted on the leading of an oval mast.

A very good weapon is the radar enhancer (See-Me) which amplifies the return. Expensive, and has a current draw, but gives a very definite target on the receiver's screen.

Another option is a radar detector, but it will be going off pretty much continously until well clear of the main shipping routes.

Following back some (trailable) motorboaters one night, we lost all but one in a modest 1-2m swell. This boat had a bright all-round white set high on a s/s pole. We could see him for miles, even when the hull vanished repeatedly.

I've also considered aluminium 'chafe' in the hull, but apparently the best reflectors need corners, so am considering sheet metal (thin aluminium) bent in strategic areas of the cabin.

Eric is also absolutely spot-on about AIS for smaller boats - just been on the boat belonging to a pair of girl contenders for the Atlantic row, and an AIS receiver is one of their main lines of defence. It's no bigger than a small fixed GPS unit, and solar panels keep it working via gel batteries.

Whilst still not entirely foolproof ( see the next issue of PBO - Nov 2007 out 5 October for a full feature on AIS and MARPA) this little set gives the bearing and range of a ship, it's name, and MMSI number. Some readers have said that this is better than a standard radar, as you know who's coming at you, and how to call them up for just a small current draw! (This bit of kit is made by the marine electronics firm Nasa.)

After all this, we're still a lot safer at sea than on a motorway!
 

PacketRat

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Damo, thanks for that, it's just the kind of information that makes a good forum. A small but cheaply won improvement in visibility.

Another thread a while back sold me on the idea of AIS. I can't assume anyone will see me on radar or visually. A cynical lookout with VHF, flares and torch handy, plus AIS is my strategy.

Robin.
 
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