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Old 10 March 2013, 12:41   #41
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Some years back I was at the press launch of a new range of RIBs. They were very new indeed, barely finished in fact, and didn't have any nav or comms gear at all.

This wasn't a problem as we were only going from Lymington over to Yarmouth for a good lunch at the George. So simple you'd think you could do it with your eyes shut.

Conditions were great, for all of a mile or so until we went slap bang into a wall of the thickest fog I've ever been in. Within about a minute we were profoundly lost, completely unable to even work out what direction we were facing. We may as well have had our eyes shut, it wouldn't have made any difference. Our lunch booking was only saved by an accompanying RIB with radar that managed to round us up and shepherd everyone to the pub.

There were four of us on board, all pretty familiar with the area, and all used to finding our way around. We weren't in any particular danger all all, but the feeling of complete helplessness is something I won't forget. An iPhone would have been really handy that day...
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Old 10 March 2013, 12:51   #42
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FWIW the echo sounder is an underused tool for navigating, as it can be used to indicate when you are getting in shallow water, and as a cross reference to your dead reckoning.

I agree that navigating solo is tricky, but you have a throttle, and can always put it to idle while you assess the situation, if it is too deep to anchor, you are not really in danger, and as for having the wife and kids, they can help by listening etc.
I'm surprised no one else has mentioned the echo sounder. It's invaluable especially in blind navigation. An echo sounder used with a paper chart and ships compass is one of the most valuable tools on a vessel in fog. Doesn't matter whether its a rowing boat or a 50m motor yacht. If you've lost all other forms of navigation aids it can get you to a safe harbour if you know how to use them correctly.

Following a 5m contour line on a chart in poor visibility gives some certainties that you ain't going to hit a 50000 tonne ship anchored in the bay or motoring across it. The only other vessel you might hit is another RIB following the same contour line into the same harbour.

Following a contour line takes practice but is very rewarding when done correctly and yes it can be done on a RIB. If your chart plotter packs up you'll need a paper chart as back up to show what's around / under you. Even a photocopy of the intended cruise area for the day is better than nothing.
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Old 10 March 2013, 13:33   #43
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cos you ARE ALL GOING TO DIE!!!!

Great stretegy
Absolutely not. As I said, I carry backup GPS/plotter, compass, watch etc. The point I was trying to make, is that paper charts aren't the silver charm that will protect you from all that is evil, some would have us believe. Unless you know where you are to start with, they are toilet paper in fog. We normally leave port heading for a fixed point, usually a wreck, the trip home is a reciprocal of the trip out.
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Old 10 March 2013, 13:58   #44
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Absolutely not. As I said, I carry backup GPS/plotter, compass, watch etc.
What? No Sunstone?

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Old 10 March 2013, 14:19   #45
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What? No Sunstone?

Very cheap too ..


http://www.ebay.co.uk/itm/5-x-Sunsto...item35c1672e7d
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Old 10 March 2013, 15:10   #46
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What? No Sunstone?

No good in fog, stick to the trusty lode stone
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Old 10 March 2013, 15:21   #47
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No good in fog, stick to the trusty lode stone
Every sensible Viking also carried a Sun stone or (Norwegian or Icelandic feldspar ) a translucent stone around his neck for use in fog or sea frets which would show up the suns position even on a grey day ,
& the old shout or yell hoping for an echo back from a cliff face .
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Old 10 March 2013, 16:15   #48
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[QUOTE=m chappelow;521652] a translucent stone around his neck for use in fog or sea frets which would show up the suns position even on a grey day ,
QUOTE]

Well I never, you learn summat new every day
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Old 10 March 2013, 17:32   #49
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Apparently you can have your chakras balanced by them too. Erm, wow?
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Old 10 March 2013, 17:42   #50
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and if you want to know the weather


http://www.theweatherstone.co.uk/

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Old 10 March 2013, 18:15   #51
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Quote:
Originally Posted by Pikey Dave View Post
Absolutely not. As I said, I carry backup GPS/plotter, compass, watch etc. The point I was trying to make, is that paper charts aren't the silver charm that will protect you from all that is evil, some would have us believe. Unless you know where you are to start with, they are toilet paper in fog. We normally leave port heading for a fixed point, usually a wreck, the trip home is a reciprocal of the trip out.
I agree they are not the "silver charm to protect from all that is evil" but they still have usefull info on them that could be used, even in fog. Cross referenced with a sounder/fish finder (if it works) it can give you a clue as to where you might be, and it will tell you what bouys etc have bells, or sound signals, all clues as to where you may be.

All together it is all info that could get you out of the S**t if your chartplotter goes tits up.
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Old 10 March 2013, 19:22   #52
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Quote:
Originally Posted by tonto

I agree they are not the "silver charm to protect from all that is evil" but they still have usefull info on them that could be used, even in fog. Cross referenced with a sounder/fish finder (if it works) it can give you a clue as to where you might be, and it will tell you what bouys etc have bells, or sound signals, all clues as to where you may be.

All together it is all info that could get you out of the S**t if your chartplotter goes tits up.
Hear hear!

Never go without paper in my view. You don't need a meticulous log to benefit from having them on board. Plot your position or write down the LL at an interval that matches your speed, conditions and the risks. If pilotage then just write the time you pass each buoy or transit. Not difficult even at speed, harder if rough or raining but these conditions are exactly when it is most important.

Even if you have 50 gps receivers on board and they are all working, unless they have every hazard and nav mark programmed in then they are just giving LL which needs to be related to a CHART.

Also you need to remain flexible when at sea, changing conditions, breakdowns, others in distress etc mean that you may need to consult a chart.

In my experience if a distress goes and the cg mentions a buoy or headland by name, it is much easier to stop, grab paper, use your fingers as dividers and then crack on.

Re earlier post, gps's give COG which is NOT heading and has nothing to do with Heading.
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Old 10 March 2013, 23:13   #53
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Unless you are keeping a meticulous log (yeah right) & know where you are & mark it every minute (on a 20knot+ RIB passage, give me strength) If it suddenly all goes dark grey you're fecked, anyone who thinks other wise is kidding themselves. Knowing you're lost is arguably safer than the bloke carrying charts who thinks he knows where he is.
True, plotting your position on a paper chart at half hr intervals or whatever the day skipper course says ain't gonna happen on a rib.

But all isn't lost, Dead Reckoning has never been an exact science. If you plot a course that has plenty of safety margin, you can afford to be much less accurate with your DR. Whilst you plotter is working properly, you're probably looking at it every few seconds to keep an eye on your CTE. Although it can be a bit demoralising on long passages, just keep an eye on your DTG (distance to go) Or even better, your eta at next waypoint. If you can remember roughly your eta and bearing to waypoint that's pretty much all you need.

If you get the dreaded black screen of death then just keep going on the same course till your eta time. I would've thought that any waypoint you had in your gps you could stick a mark on a paper chart with reasonable accuracy? You can then plot a new course to the next waypoint, a quick time/distance calc to know how long to run for. I wouldn't be too fussy about calculating tidal set, you should know roughly what it's doing, if there's a strong tide on your port beam, then steer a few degrees to port, if its on the nose then expect to run for a bit longer. There's no point in trying to be super accurate, it's impossible to hold an accurate course. Although if go slow enough, preferably off the plane, you might be surprised, I was the first time I was forced into it.

When choosing a course to steer back to port in fog, isolated rocks are probably your biggest danger, gently sloping shores are your friend if you have a sounder. Many harbours will have some sort of buoyage offshore, perfect for plotting a course to, if when you think you should be at the buoy, you can't see it, set up a suitable search pattern until you do find it then you can safely plot a new course home.

IMO paper charts are pure gold, the amount of info on them if you know what you're looking at is staggering. True, these days I have an actual chart drawer as well as a chart table but also on the rib I wouldn't be without them. And there's plenty of other handy tips on here for keeping pilotage/nav/tide info on board, have laminator, will travel...

In the days when GPS was still pretty new and electronic charts were still a few years off, paper charts were my paddle out of s**t creek a few times and allowed for changes of plan etc when I didn't have waypoints stored on my little garmin 45.

Next time I get a can of red bull out the fridge after 2200, somebody stop me, pleeease....
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Old 10 March 2013, 23:31   #54
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Originally Posted by John Kennett View Post
There were four of us on board, all pretty familiar with the area, and all used to finding our way around. We weren't in any particular danger all all, but the feeling of complete helplessness is something I won't forget. An iPhone would have been really handy that day...
But so would a compass!

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A bloke on a rib my have a small GPS screen and his Wife and kids to worry about.
Does modern electronic navigation make it too easy for Mr Rib to head to sea with his family having done no proper passage planning? I know Mrs P is amazed at how much time I spend pouring over charts before I go anywhere new.

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Agreed, offshore, fog is not such a biggy. Inshore, crab pots a 55000 tonnes of parked steel are.

Fal Bay is the NCP for N. Atlantic shipping waiting for a job.
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It's scary stuff. There's a thread on here somewhere, where Roy Cruse, Bob Keeper and Myself got caught in thick fog coming back from Kynance to Mylor. We were so concerned about hitting anchored shipping in the Bay and Carrick Roads, we were comm'd back to Mylor by Falmouth Coastguard who had us and the ships on radar.
I remember your story well, but would an iPad have helped? not really unless you are going to trust the phone signal and some AIS app to guide you through the ships. Your 'old fashioned' approach of slowing right down and talking to people with radar seems rather sensible.

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True, plotting your position on a paper chart at half hr intervals or whatever the day skipper course says ain't gonna happen on a rib.
I've been on a rib where thats been done. Can't say the points were that accurate, but it was an old school GPS (no plotter) and laminated chart - it worked surprisingly well even in a chop - just to make sure that nobody had miskeyed the waypoints etc.
Quote:
But all isn't lost, Dead Reckoning has never been an exact science. If you plot a course that has plenty of safety margin, you can afford to be much less accurate with your DR. Whilst you plotter is working properly, you're probably looking at it every few seconds to keep an eye on your CTE. Although it can be a bit demoralising on long passages, just keep an eye on your DTG (distance to go) Or even better, your eta at next waypoint. If you can remember roughly your eta and bearing to waypoint that's pretty much all you need.

If you get the dreaded black screen of death then just keep going on the same course till your eta time. I would've thought that any waypoint you had in your gps you could stick a mark on a paper chart with reasonable accuracy? You can then plot a new course to the next waypoint, a quick time/distance calc to know how long to run for. I wouldn't be too fussy about calculating tidal set, you should know roughly what it's doing, if there's a strong tide on your port beam, then steer a few degrees to port, if its on the nose then expect to run for a bit longer. There's no point in trying to be super accurate, it's impossible to hold an accurate course. Although if go slow enough, preferably off the plane, you might be surprised, I was the first time I was forced into it.


Oh no I'm agreeing with both Mollers and Martini in the same post... what is the world coming to.
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Old 10 March 2013, 23:34   #55
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People like Sir Cloudesley Shovell for instance: Cloudesley Shovell - Wikipedia, the free encyclopedia
In my experience fog usually = quite calm. It was a storm that did for Cloudesley Shovell.
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Old 11 March 2013, 07:16   #56
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Oh no I'm agreeing with both Mollers and Martini in the same post... what is the world coming to.
We've both got a good few years and plenty of sea miles under our belts in a wide variety of craft - it's a credit to you
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Old 11 March 2013, 07:46   #57
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Do you not have a proper compass on your console? Using GPS to determine heading is rubbish because it shows you is the average heading that you were on a moment ago - not where you are heading now. Steering a compass course is a skill (whether on a rib or any other boat) - it was covered in my PB2. There might be a "magnetic" compass in your phone too - but it will be heavily damped so I doubt its accurate / precise enough to navigate properly by.

How bad was the Vis? 15 knots still sounds quite fast if you can't see anything. How quick can you stop / avoid an obstacle?
Yes we have a good compass and were using it steer a bearing based on where we were and where we wanted to get to. However your right it's a skill to keep a rib on a constant course so we regularly checked the GPS to ensure we were where we expected to be.

It was a case of keeping one eye on the compass and one eye on the compass and another for fishing boats travelling at speed with no running lights !

Vis was about 100 meters. 15 knots was the speed we needed to maintain in order to get back before light started to fail.
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Old 11 March 2013, 07:47   #58
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Yes we have a good compass and were using it steer a bearing based on where we were and where we wanted to get to. However your right it's a skill to keep a rib on a constant course so we regularly checked the GPS to ensure we were where we expected to be.

It was a case of keeping one eye on the compass and one eye on the compass and another for fishing boats travelling at speed with no running lights !

Vis was about 100 meters. 15 knots was the speed we needed to maintain in order to get back before light started to fail.
Rule 6
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Old 11 March 2013, 07:59   #59
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I'm surprised no one else has mentioned the echo sounder. It's invaluable especially in blind navigation..
The echo sounder was actually working and was also watched making sure we kept well out from the coast. We were running in about 60 meters of water so knew we were staying safe in that aspect.

Where the Handheld came into its own was finding the way into Teignmouth.
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Old 11 March 2013, 08:06   #60
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Rule 6
Exactly and at 15 knots we could stop well within the available visibility.
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