Reply
 
Thread Tools Search this Thread
 
Old 08 December 2008, 07:56   #21
Member
 
Pete7's Avatar
 
Country: UK - England
Town: Gosport
Boat name: April Lass
Make: Moody 31
Length: 9m +
Join Date: Aug 2001
Posts: 4,951
Quote:
Originally Posted by chewy View Post
At the end of the day its upto the individual but I personally would deploy the sea anchor.
Do you carry one? we have a Drogue on board which could be deployed as a sea anchor just we have never tried it. However I don't think it has to be anything special, a bucket or pair of sailing salopettes could be used.

Quote:
Originally Posted by chewy View Post
Can anyone explain how filling the boat with water actually stops the boat from been beam onto the sea?
I don't think it does, I think flooding the hull is more about increasing stability and reducing the possibility of a breaking wave capsizing the rib. Alan does explain it in his first book. those interested in reading more about his idea perhaps should look on Amazon for a copy.

Pete
__________________
.
Ribnet is best viewed on a computer of some sort
Pete7 is offline   Reply With Quote
Old 08 December 2008, 08:50   #22
Member
 
chewy's Avatar
 
Country: UK - England
Town: Up Norf
Make: Avon SR4,Tremlett 23
Length: 4m +
Engine: Yam 55, Volvo 200
Join Date: Apr 2007
Posts: 5,217
I never said it was bad advice Alan. What I do know is that a boat with no sea anchor will get washed up the beach and one with a sea anchor deployed will ride the waves, it will probably end up on the beach but will have given the crew chance to fix things.

I've just bought a sea anchor for my SR, it not been in the water yet due to it been refurbed.

I've used sea anchors loads of times on the Atlantics and they work. Why do the RNLI fit them? If you capsize you deploy the sea anchor so when the boat rights again its facing the weather so it doesn't go over again.

I'm sure in the sort of RIBs you use Alan your method works but I'd prefer to ride it out facing the weather rather than just bobbing and surfing all over the place.
__________________
chewy is offline   Reply With Quote
Old 08 December 2008, 09:36   #23
Member
 
Country: UK - England
Town: Southampton
Boat name: Yoda & Obi Wan
Make: XS700
Length: 7m +
Engine: 200 HP
Join Date: May 2004
Posts: 1,032
Quote:
Originally Posted by Alan Priddy View Post
Better still, dont use it. We worked a long time on establish if a sea anchor would work in big seas and the boat ended up being safer without. I would always advocate filling the boat with water if you cannot make headway in big seas or are drifting on to a lee shore.
Not quite the "RYA" way but then again, have they ever had to survive in bad conditions
If I read this right you are saying you would prefer to allow your boat to blown beam on and be full of water in bad condition when trying to keep of a lee shore.

Quote:
Originally Posted by Jono Garton View Post
Until the tubes come off, my 6.3 Ocean Pro holds 5 tonnes of water! Personally I like the water not in the boat.
Call me old fashioned but I think I would agree with Jono on this one

Lesson 101 in capsizing a boat (not making way).

As a general rule it’s a breaking wave that will capsize the boat. As a rule of thumb it is fairly well accepted that a beam on breaking waves that’s height is equal to the beam of your vessel may capsize you, bigger than that more likely. It’s also generally accepted that if you are bow to the waves the breaking wave will need to be over 80% of the boats length to capsize you.

Do the sums and we can see pretty clearly that any techniques that hold the bow to the waves are likely to prevail over a technique that allows the boat to be beam on to the same breaking waves.

The sea anchor does just that, deployed from the bow it avoids you becoming beam on, given a long enough line it also increase the 80% margin quite considerably as it provides some resistance for the bow.

The RNLI I believe fit a sea anchor as standard on their Atlantics- I have certainly seen a few clips where quick deployment was the one factor that saved the boat from impending disaster.

We have spent considerable time experimenting with sea anchors, although much of it has been from larger racing yachts. On the two occasions we did it from a 7m ish RIB in rough weather the sea anchor was not sufficient to hold the bow to sea/wind, my conclusion was simply the sea anchor on the boat was not big enough for the boat. It was in fact the same as the sea anchors that come with a standard SOLAS life raft. The life raft of course has the benefit of ballast bags which the RIB does not.

I have also spent time with my boat full of water, however this was never intentional, as already mentioned there are issues of electrics, fuel tank breathers, hypothermia etc, however to my mind filling the boat with water kind of defeats the objective of having a boat in the first place. I hope I never get into a situation where my mind remembers this thread and start to wonder if it is the appropriate action.
__________________
Doug Stormforce is offline   Reply With Quote
Old 08 December 2008, 11:00   #24
Member
 
chewy's Avatar
 
Country: UK - England
Town: Up Norf
Make: Avon SR4,Tremlett 23
Length: 4m +
Engine: Yam 55, Volvo 200
Join Date: Apr 2007
Posts: 5,217
At last someone sees sense rather than just agreeing.

Indeed all Atlantics are fitted with sea anchors and are permanently fitted in the bow, they can be deployed from the stern in the eent of a capsize.
__________________
chewy is offline   Reply With Quote
Old 08 December 2008, 11:12   #25
Member
 
Country: UK - England
Town: Portsmouth
Boat name: Not sure
Make: ABC/Priddy
Length: 10m +
Engine: 2 x 500 FPT
Join Date: Jul 2001
Posts: 928
All.

Whilst I accept that there are always training manuals and courses for this, there are times when the conditions and situations are so bad the "Written Rules" will not work.

Here is the simple version of why I would always advocate filling a boat with water. By flooding the hull, the displacement will go below the waterline and the craft will become part of the sea and rise up and down with each wave or breaking wave. Holding the bow into big seas in a small boat can cause more problems than expected, ie the wave will roll over the bow and in some cases pitchpole the entire craft and crew. On a lee shore the craft should rise up and down over the hazards of rocks etc and get you closer to shore so you have a better chance of not being smashed to pieces on the rocks. Of course the boat is a total write off but you and the crew should live to tell the tale.

It has to accepted that unless you have tried any of this in BIG seas, comments can only be made from courses that you have attended and books you have read.

So here is my experiance of bad weather over the past few years

RIBS

1997. 7.4 metre rib, North Atlantic coming back from USA via Greenland 55 knots lying a hull for 12 hours.
2000 10 metre rib 50 miles NW of Ireland 45 knots lying a hull for 20 hours.
2001 10 metre boat, 1000 miles off Canada Coming from New York to UK, 50 knots of wind and three converging storms (Hell) lying a hull for 15 hours.
2002 10 metre Rib 70 knots in the South China Seas 18 hours.
2002 10 metre rib 120 knots in Hurricaine Hannah, Canada. We went out for a play to see what would happen. After this I gave the sea anchor and drouge to The Royal Newfoundland Yacht Club to auction for charity as it was a waste of time to carry it..
2003 10 Metre rib 77 knots off the tip of Greenland 8 hours.
And we lived to tell the tale so in this case, there is a very good reason for flooding the hull.
I guess that one of the main things is to make sure your craft is built right in the first place and all the electrics are waterproofed. The other alternative is to look at the wetaher forecast and not go out in it!

Sailing

2006 Lively Lady 36 foot sailing yacht 50 knots North Atlantic 48 hours bare poled.
2006 Lively Lady 55 knots South Carolina 12 hours.
2007 Lively Lady 70 knots Wilsons promitary Australia. ( this is the area that the Sydney Hobart went all wrong.

The rest really doesnt matter but as I said earlier, What do I know? Everything that the skipper does has to be down to his skills and past experiances. I have sailed with many good skippers who have got in to lots of trouble by "Sailing by the Book"

Only experiance will teach you lessons

Alan P
__________________
Alan Priddy is offline   Reply With Quote
Old 08 December 2008, 11:19   #26
Member
 
Country: UK - England
Town: Mayfair, London
Make: RibEye/Ferretti 881
Length: 7m +
Engine: Yamaha 25/Twin MTU
Join Date: Oct 2002
Posts: 691
Quote:
Originally Posted by Alan Priddy View Post
Hey, what do I know?????????????????
AS for bad advice, Before you all knock what I am saying, wait for a really bad day and try it.
A fully water logged boat of any discripton is better than something sitting on top of the water in any conditions.
Alan P
I have no idea what you do know and what you don't know.

However your statement above is nonsense. "A fully water logged boat of any discription (sic) is better...".
Of any description? Many boats would break up far more easily in rough seas when water logged rather than if fully buoyant and riding the waves.
__________________
timw is offline   Reply With Quote
Old 08 December 2008, 11:33   #27
Member
 
Country: UK - England
Town: Dorset & Hants
Boat name: Streaker/Orange
Make: Avon/Ribcraft
Length: 4m +
Engine: 50Yam/25 Mariner
Join Date: Apr 2007
Posts: 5,551
Tim - I think you need to put this into context - Alan has far more experiance than most of us. If there were me & him in a boat & its was all going tits up - I'd let him make the call on the best course of action every time.

Part of being a decent skipper is knowning when to learn from others experiance/ mistakes / whatever you want to call it.

In this case its not bouyancy thats in disput - its stablity / risk of capsize & being blown onto a lee shore. A fully bouyant rib has bugger all under the water & will be blown very quickly . Put a couple of tonnes of water in it & it takes a lot more wind to move it the same speed/ distance . Likewise a wave will flip a light boat far easier than a heavy one with the weight at the bottom - just look at yachts - its why they have a bloody great big weight hanging under them .
__________________
PeterM is offline   Reply With Quote
Old 08 December 2008, 11:38   #28
Member
 
chewy's Avatar
 
Country: UK - England
Town: Up Norf
Make: Avon SR4,Tremlett 23
Length: 4m +
Engine: Yam 55, Volvo 200
Join Date: Apr 2007
Posts: 5,217
Cheers Alan. How do the RIBs lie without any drogue and full of water?
Do you intentionally fill the RIB with water or just let nature take its course.
We can't fill the Atlantics due to the open transom.
Do you get problems with the engine with the boat sitting so much lower in the water, ie water ingress through exhaust etc?
__________________
chewy is offline   Reply With Quote
Old 08 December 2008, 13:42   #29
Member
 
Country: UK - England
Town: Portsmouth
Boat name: Not sure
Make: ABC/Priddy
Length: 10m +
Engine: 2 x 500 FPT
Join Date: Jul 2001
Posts: 928
Chewy. in my experiance, they lie fine, I am here to tell you about it so that must mean something. We leave the scuppers down and nature does the rest.
Our engine boxes are always water tight and the breathers at the highest possible point. As a rule, outboards are pretty much water tight and dont present too many problems that a good can of WD40 wont sort out.
Timw.
Outside water pressure against inside water pressure = Zero so why should it break up unless it was a piece of crap in the first place? As I said, there is no subsitute for a well prepaired craft and half a million sea miles and every ocean does give me the edge over a lot of people. The other thing to take into consideration on a lee shore is once you ruduce the windage, the current runs up and down most coastlines which will give you a better chance of survival. Again, I am talking about conditions that the rescue services would find it difficult to help you with apart from above.
The RIBNET Forum is here for people to ask advice and for others to pass it on. I only speak from experiance, if it is to be disregared, so be it and in the unfortunate event of a mishap you must make your own mind up as to how you deal with it, We all have our own lives to live and although I am sure that I have used up more than my fair share of mine, I am still here.
Alan P
__________________
Alan Priddy is offline   Reply With Quote
Old 08 December 2008, 14:26   #30
Member
 
chewy's Avatar
 
Country: UK - England
Town: Up Norf
Make: Avon SR4,Tremlett 23
Length: 4m +
Engine: Yam 55, Volvo 200
Join Date: Apr 2007
Posts: 5,217
Thanks Alan, its good to hear other people expeirences and methods.
Not sure if I should block the flooding hull on my SR up now!
__________________
chewy is offline   Reply With Quote
Old 08 December 2008, 16:35   #31
Member
 
Country: UK - Wales
Town: Pwllheli-North Wales
Boat name: V-ONE
Make: Highfield
Length: 8m +
Engine: Honda 250hp
Join Date: Mar 2001
Posts: 2,367
Quote:
Originally Posted by Alan Priddy View Post
RIBS

1997. 7.4 metre rib, North Atlantic coming back from USA via Greenland 55 knots lying a hull for 12 hours.
2000 10 metre rib 50 miles NW of Ireland 45 knots lying a hull for 20 hours.
2001 10 metre boat, 1000 miles off Canada Coming from New York to UK, 50 knots of wind and three converging storms (Hell) lying a hull for 15 hours.
2002 10 metre Rib 70 knots in the South China Seas 18 hours.
2002 10 metre rib 120 knots in Hurricaine Hannah, Canada. We went out for a play to see what would happen. After this I gave the sea anchor and drouge to The Royal Newfoundland Yacht Club to auction for charity as it was a waste of time to carry it..
2003 10 Metre rib 77 knots off the tip of Greenland 8 hours.
And we lived to tell the tale so in this case, there is a very good reason for flooding the hull.
I guess that one of the main things is to make sure your craft is built right in the first place and all the electrics are waterproofed. The other alternative is to look at the wetaher forecast and not go out in it!

Sailing

2006 Lively Lady 36 foot sailing yacht 50 knots North Atlantic 48 hours bare poled.
2006 Lively Lady 55 knots South Carolina 12 hours.
2007 Lively Lady 70 knots Wilsons promitary Australia. ( this is the area that the Sydney Hobart went all wrong.

The rest really doesnt matter but as I said earlier, What do I know? Everything that the skipper does has to be down to his skills and past experiances. I have sailed with many good skippers who have got in to lots of trouble by "Sailing by the Book"
Alan

What a CV

I'm not going to comment further as you don't talk any sense.

Jono
__________________
www.waterwise-marine.co.uk
Jono Garton is offline   Reply With Quote
Old 08 December 2008, 18:06   #32
K&S
Member
 
Country: UK - Scotland
Town: Glasgow
Boat name: Riberty
Make: xs 650
Length: 6m +
Engine: suzuki 175
MMSI: 235063328
Join Date: Aug 2007
Posts: 377
Quote:
Originally Posted by Alan Priddy View Post
Hey, what do I know?????????????????
AS for bad advice, Before you all knock what I am saying, wait for a really bad day and try it.
A fully water logged boat of any discripton is better than something sitting on top of the water in any conditions.
Alan P
Not sure i agree with this 100%.
I understand to a point what you are saying. True a Searider with flooding hull is stable in all but the worst conditions but adding water to the inside of most boats i'm not with you on that one.

Having had a searider stuff in conditions far better than the conditions that you describe with the engine still going was a bit hair raising. The best tacktic was to get going with the waves to help empty it.

As for deliberately filling the boat and await our fait i dont think so, first of all the crew would have thought i had gone completely mad and second i'd be more inclined to get the boat anchored / stabalised with nose into the waves so at least the waves were coming in one direction rather than sitting broad side waiting to be 'bongo sliding' towads a lee shore

In conditions where i thought deliberately filling the boat to aid safety was a wise idea then perhaps i needed my head examining earlier in the day for going out
__________________
K&S is offline   Reply With Quote
Old 08 December 2008, 18:18   #33
RIBnet admin team
 
Nos4r2's Avatar
 
Country: UK - England
Town: The wilds of Wiltshire
Boat name: Dominator
Make: SR5.4
Length: 7m +
Engine: Yam 85
MMSI: 235055163
Join Date: Jul 2005
Posts: 13,054
RIBase
I'm with Alan on this (and no, I'm not blindly ageeing)

After stuffing both my seariders by being a pillock and going too fast in quite nasty weather,they moved very little when full of water to the transom.It's a bit disconcerting though!

I've also tried using a sea anchor on a rib on a few occasions. and there rarely seems to be quite enough windage to actually tension the line unless I could get a really good throw so the anchor ends up over the peak of the next wave.Unfortunately (it might be down to my sea anchor) it's not easy to throw what's effectively a parachute into the wind.

However, I tend to agree with K&S in the quote below far more!

Quote:
Originally Posted by K&S View Post

In conditions where i thought deliberately filling the boat to aid safety was a wise idea then perhaps i needed my head examining earlier in the day for going out
__________________
Need spares,consoles,consumables,hire,training or even a new boat?

Please click HERE and HERE and support our Trade Members.

Join up as a Trade member or Supporter HERE
Nos4r2 is offline   Reply With Quote
Old 08 December 2008, 18:21   #34
Member
 
chewy's Avatar
 
Country: UK - England
Town: Up Norf
Make: Avon SR4,Tremlett 23
Length: 4m +
Engine: Yam 55, Volvo 200
Join Date: Apr 2007
Posts: 5,217
I was totally against Alans theory of filling my boat with water but considering the type of "cruising" he does who am I to argue. If thats what works in the middle of know where then so be it, horses for courses really.
__________________
chewy is offline   Reply With Quote
Old 08 December 2008, 18:26   #35
K&S
Member
 
Country: UK - Scotland
Town: Glasgow
Boat name: Riberty
Make: xs 650
Length: 6m +
Engine: suzuki 175
MMSI: 235063328
Join Date: Aug 2007
Posts: 377
Quote:
Originally Posted by chewy View Post
I was totally against Alans theory of filling my boat with water but considering the type of "cruising" he does who am I to argue. If thats what works in the middle of know where then so be it, horses for courses really.
True its an impressive C.V.

However, i have to say that in ribbing terms most of my 'Sh%T what should i do now' moments have actually been on inland waters where you least expect them.

I'd far rather be in trouble in 3m high rounded waves in a larger rib than in a 4m rib in a steep breaking chop.
__________________
K&S is offline   Reply With Quote
Old 08 December 2008, 18:28   #36
Member
 
Pete7's Avatar
 
Country: UK - England
Town: Gosport
Boat name: April Lass
Make: Moody 31
Length: 9m +
Join Date: Aug 2001
Posts: 4,951
Quote:
Originally Posted by chewy View Post
Thanks Alan, its good to hear other people expeirences and methods. Not sure if I should block the flooding hull on my SR up now!
Yes block it up. Here is my two pence worth:

In anything up to F8 I think you are better off keeping the rib moving and away from breaking waves, particularly on an average sized outboard powered rib. Modern ribs have superb power to weight ratio you really can drive the rib around the waves even if it means a long series of diagonal tracks to get home, rather than a straight line into the waves. You will be suprised at the angle you can cross the face of a wave to get over the top even when there doesn't appear any water under the down side of the rib. Downwind, use the throttle with bottle, but you will tire and start making mistakes and that could be your downfall. Change if you have other experienced crew.

F8 and above, firstly what were you thinking off? offshore you may find the waves have a pattern which you can keep moving, but close inshore with shallow water or wind against tide / current conditions you are in trouble. What ever you choose to do you may find that changing your mind not an option. There will be no chance of pulling in a sea anchor unless it has a trip line and even then leave a large amount of line in the water until it is recovered during which you are going to drift sideways. Flood the hull, do you have suficient pumps to empty the hull quickly on the average rib? or are you hoping the trick of a quick blast which worked so well in the Solent during a hot summers day will do the trick only now you are down to 8-9 knots tops and in big waves. I am against Alans idea, not because I don't think it would work but I don't think most ribs are designed for it, especially the electronics.

One early experience involved a passage from Scrabster round into the North Sea in 92. Interestingly Alan was their. A good Easterly was blowing the North Sea across the top of the Atlantic moving West causing huge breaking waves to well up and then quickly disappear only to leave a trough in its place. Alan and the other two round GB boats had stopped in calmer water about 100 yards off the malestrom. We approached in a little 5.2m rib with just 60 hp. The driver asked me what we should do, I suggested he go for it but time the bursts of throttle carefully to work our way through the waves. After a mile we were relieved to see calmer water ahead. Later he asked me why there was footprints on the front of the outboard. I pointed out that I couldn't keep my feet on the deck so held onto the backrest and put my feet on the cowling which was much nearer the horizontal.

Thankfully in this country the weather forecasts whilst may not be exact normally foretell when it's going to be serious. I don't think folk are going to be caught out like Alan well offshore but could be caught out rounding a headland or entering an estuary. The difference in waves in the entrance to Strangford Lough between a flood and ebb tide with an onshore wind needs to be seen to be believed.

Pete
__________________
.
Ribnet is best viewed on a computer of some sort
Pete7 is offline   Reply With Quote
Old 08 December 2008, 18:53   #37
Member
 
chewy's Avatar
 
Country: UK - England
Town: Up Norf
Make: Avon SR4,Tremlett 23
Length: 4m +
Engine: Yam 55, Volvo 200
Join Date: Apr 2007
Posts: 5,217
Quote:
Originally Posted by Nos4r2 View Post
I've also tried using a sea anchor on a rib on a few occasions. and there rarely seems to be quite enough windage to actually tension the line unless I could get a really good throw so the anchor ends up over the peak of the next wave.Unfortunately (it might be down to my sea anchor) it's not easy to throw what's effectively a parachute into the wind.
Thats because its not rough enough!
__________________
chewy is offline   Reply With Quote
Old 08 December 2008, 19:09   #38
Member
 
m chappelow's Avatar
 
Country: UK - England
Town: yorkshire
Boat name: little vicky
Make: avon ex RNLI
Length: 3m +
Engine: tohatsu
Join Date: Mar 2008
Posts: 2,310
i have carried and used sea anchors for years on ribs and sibs but you will find that unless there is a strong wind most boats will lie across the tide beam on ,and what i have found is they work better with a hole in the middle otherwise they can be too effective and start to snatch rather than have a constant pull.,also have a tripping line attached other wise they can be hard to pull back in a big sea .one of the bst ones i had was made from a sleeve from an old pvc fishing smock with some brass eyes put in ,when i was deep sea fishing off iceland we used to use an old tractor tyre .once heard of someone using a seagull outboard as a sea anchor on a sailing yacht in a mid atlantic storm as the normal sea anchor had blown out ,
__________________
m chappelow is offline   Reply With Quote
Old 08 December 2008, 19:14   #39
RIBnet admin team
 
Nos4r2's Avatar
 
Country: UK - England
Town: The wilds of Wiltshire
Boat name: Dominator
Make: SR5.4
Length: 7m +
Engine: Yam 85
MMSI: 235055163
Join Date: Jul 2005
Posts: 13,054
RIBase
Quote:
Originally Posted by chewy View Post
Thats because its not rough enough!
Fair comment-I've been lucky enough not to have to deploy one in bad conditions except on a yacht when the forestay parted-but obviously that's not a rib...
__________________
Need spares,consoles,consumables,hire,training or even a new boat?

Please click HERE and HERE and support our Trade Members.

Join up as a Trade member or Supporter HERE
Nos4r2 is offline   Reply With Quote
Old 08 December 2008, 23:05   #40
RIBnet Supporter
 
willk's Avatar
 
Country: Ireland
Length: 4m +
Join Date: Feb 2008
Posts: 14,681
Quote:
Originally Posted by Alan Priddy View Post
Timw.
Outside water pressure against inside water pressure = Zero so why should it break up unless it was a piece of crap in the first place? As I said,
etc etc

Probably not the week to mention it Alan (sausages) , but we have a saying here - "Never wrestle a pig in it's own sh1t - the audience soon can't tell one party from the other"

I was present at one incident where your flooding technique would have helped a lot (had we had the presence of mind to employ it). It does however, run contrary to every instinct a boater has (keep the water out of the boat). As a diver I know that one is often safer in (under) the water than drifting on it. Makes sense with a boat too
__________________
willk is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




All times are GMT. The time now is 01:23.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.