March WNS

A good friend of mine and a business colleague of his took a RIB out from Yarmouth, IoW in May 2006. Somewhere off Yarmouth, the boat stopped violently (for reasons unexplained even by the subsequent investigation) throwing both men out of the boat into the water. Both were wearing buoyancy aids and were in the water for 30mins before being spotted by a Wightlink ferry and hauled aboard. My friend was unconscious and could not be resuscitated. His colleague survived. Story HERE
The received wisdom is that you've got maybe 30mins in the E Channel at it's coldest and maybe up to 1 hour at it's warmest unless you're wearing some kind of immersion suit. It is also said that the more fat you carry, the longer you will last which is probably why my friend's colleague survived.
Going back to this WNS, maybe the sea was at it's warmest for the season but the MOB is a teenager, probably scrawny as most teenagers are, so maybe 1 hour is being optimistic
 
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Remind sailors (not mobos) of the benefit of Raymarine's remote control for the AP

[/ QUOTE ]Iirc, there's some similar gizmo also for MoBos - obviously cutting engine(s) rather tan A/P.
Can't say by heart where I read about it, though.
 
I deleted my post because I thought I had overstepped the line between banter and rudeness and I have no personal animus against Tony who, if nothing else, gets us all talking once a month.
 
MAYDAY as soon as it's clear he is not aboard. The sooner CG aware the sooner the SAR operation starts - lifeboats/helicopters/etc. aren't instant resources despite how it sometimes seems. They can always be stood down. Also alerts other vessels in the area - some of which may have rescue boats available.

Also bear in mind that even if you can see and quickly recover him he may still need to go to hospital or require some form of first aid treatment.

W.
 
I m with you.. anyone overboard who isnt themselves then also laughing and swimming,is a Mayday. Time is vital, and, as you say, you can always cancel it. Finding it takes 20 mins to get someone back on board, or even you cant get them back on board... well, why lose that time...
 
Everyone keeps mentioning taking the tide into account.
But the tide will have been affecting the person and the boat in exactly the same way ever since he fell in. So if you just steer the reciprical (sp?) of your course, not your track, you should get straight back to the MOB. Assuming you've been steering a straight line of course.
 
although I would agree with many comments about it being an unlikely situation. does it really matter? we have all had an opportunity to think about what we would do, those more knowledgeable have helped those less so and at the least may have provoked some thoughts to those who would look at sorting fenders at 20kts!
 
I'll happily be corrected if i've gone wrong here but I don't think that's correct flaming.

Let's say the tide is running N to S, and as you were driving into the harbour your ground track was due West. Because of the tide the boat's heading was, say, 275degress, not the 270 it would have been without tide

When you turn around the reciprocal course is 95degrees. That's the wrong answer, because it doesn't allow for the fact the tide is now pushing your port side not your starboard side. In other words, you will suffer an actual tidal drift effect of 5 deg (at 20knots), and you're adding another 5 to your 095 heading. Ground track is then 100deg

Your boat speed of 20kts into the harbour is an element of the 5deg calc. If you were doing 10kts to the harbour, you would have needed about 10deg of correction, ie a heading of 280deg. The boy in the water is doing zero knots east-west, and just being carried by a 2 knot tide, so he has done 20knots relative to you. So the offset needed to your ground track to reach him is found from the tangent/sine* thing Deleted User and I debated, ie it is the angle whose tan/sine is 0.1, which is of course the same angle as your HDG/COG different on entry to the harbour, namely 5deg. So you want a ground track to reach him of 95 degrees. You dont want a heading of 95degrees, cos that will give you a ground track of 100 degrees, at 20kts. So if you charge at him at 20kts you'll need to include in your maths (a) the fact you want a 95 ground track plus (b) tidal correction of 5 degrees the other way (ie steer 5 deg less) which means a heading of 090.

That said, you wouldn't do all this maths, you'd just guess and look for the boy. But a receiprocal course could give you a bad error in a strong tide and a slow boat.

* In the post a few above I said cosine. It should have been sine, doh!
 
"There’s now a F3/F4 on the nose against a 2kt flooding tide, it’s started to rain and the visibility is poor."

Perhaps then would have been a good time to all get below in the shelter of the saloon out of the weather before it gets even worse ,bit less rolly downstairs and bonus you could keep an eye on all the crew and areas they need to access ?
 
He's a really clever boy then. He saved at least one man's life
 
course, track, heading .....

easy to get it wrong ...

I know what flaming is saying and if he substituted "heading" for "course" then I'd be 100% behind him ....

Fact of the matter is - at 20 knots heading in to a harbour you ain't steering a compass course .... unless you're a complete numpty!!
 
as one that ties on the fenders, you cannot seriously move on a flybridge boat doing 20 knots, & at 20 knots you would not go near the lazerette for fear falling down in there.

Overboard, doubt it, too busy hanging on. Fender sorting is for when its mostly calm, its not a danger sport, or at least its not for me.
 
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You are half a mile out, right? At 20 knots and 5 minutes, you are now approximately a mile inland.
Put out the boarding ladder, climb down and walk back along the enormous trench your props have dug, and you should find him covered in mud somewhere.

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That's the funniest post I've ever read on here - Brilliant
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Sorry tony but this ridiculous wns senario has crashed and burned!
 
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substituted "heading" for "course" then I'd be 100% behind him ....

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Erk, no. If you did a reciprocal then the heading adjustment you were making on your heading as you thrashed into the harbour to allow for the tide would become the wrong way round on your new course, ie you'd have added it not subtracted it or vice versa. But I agree none of this much matters!
 
No offense taken.

Regarding the fenders, by using the word 'prepare' I was thinking of getting them out of the lazarette and perhaps tying the aft ones on to the guard rail while leaving them inboard ready to be flipped over once inside the harbour. I deliberately avoided the word 'rig' as that would, indeed, have been stupid.

IMHO, sending a young person down to the cockpit to do this is reasonable. The 'lid up/cockpit gate open' bit was a bit Sherlock Holmesy and - as others have pointed out - I should have gone for a simpler reason for the MOB.

Your contributions to WNS are much appreciated. I may make cockups, but the thing still works as a debating/educational forum.

Best wishes
TJ
 
No, they're for pulling the boat back into the water from where it finished up a considerable distance inland. I'm disappointed that no one volunteered a viable technique for this. /forums/images/graemlins/frown.gif

Best wishes
TJ
 
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And do the theme assuming a competent skipper with a good plotter, instead of piling on unlikely scenarios like a busted plotter.

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Jfm

Thanks for your most helpful and thoughtful suggestions.

The reason I 'broke' the chartplotter is that many can lay down a trace of the boats passage is asked to do so. Back tracking in that situation presents no problems.

I originally set the turn in point at 1/2 mile, then realised that that wouldn't give much of a search problem either so changed it to 5 min at 20kt - and forget to change the original text. Doh. /forums/images/graemlins/frown.gif

Great to have you sticking with WNS. Your input makes getting hammered for my errors well worthwhile. /forums/images/graemlins/smile.gif

Best wishes
TJ
 
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