Sea Anchor Drogue line diameter?

One of the reasons for having a significant length of line is to be able to position the chute anchor call it what you will in such a position that it is not pulled out of the water when the boat rises on a large wave and mid atlantic you are likely to need more than 60 M.

In general I used to find that Lalizas kit was budget stuff at best and that is being kind so draw your own conclusions.

If your boat can heave to then providing you cross at reasonable times i.e. not a winter crossing of the northern route you should want for nothing more. If you still want something look at plans for a Jordan drogue and make one yourself, time consuming but not difficult.
 
on this occasion, I think the RNLI is the best source of information. They have drogue streamed behind the boat which then provides a positive control input to the steering.

http://www.poolelifeboats.org.uk/2012/09/23/rough-weather-boathandling-and-deploying-a-drogue/


That the small multi-cone drogues work is not doubted, but they are astonishingly fussy to make, to store and to deploy, as well as being expensive. They look like an over-technical answer to a simple question. A drogue system needs to be simple to build, easy to deploy and recover, capable of being adjusted for lateral control, able to be varied in its drag load (vehicle brakes are not fully ON or fully OFF :) ), scalable, and easy to store.

I haven't found an answer yet.
 
There was a thread somewhere on drogues and sea anchors, I don't recall - but the thread had a focus toward attachment points on the yacht. Thinwater was a key contributor (I was simply an interested bystander) but having any of these devices has other implications, how do you deploy and what do you attach it to.

Before you decide to go through with this maybe a comment on what you are going to attach it to might be in order.

Or am I speaking out of turn?

Jonathan
 
Neeves said:
There was a thread somewhere on drogues and sea anchors, I don't recall - but the thread had a focus toward attachment points on the yacht. Thinwater was a key contributor (I was simply an interested bystander) but having any of these devices has other implications, how do you deploy and what do you attach it to.

Before you decide to go through with this maybe a comment on what you are going to attach it to might be in order.

Or am I speaking out of turn?

Jonathan
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I have the two cleats at the bow, two mid cleats if required and the windlass post in the middle of the foredeck. The double bow roller is also substantial and well attached (for an AWB, I know they are lighweight Tupperware), and capable of providing an anchor point also( if I gave it a minute's thought).
At the back are the two outer cleats and the main winches.

I wonder how Shane Acton got on?
 
FullCircle said:
I have the two cleats at the bow, two mid cleats if required and the windlass post in the middle of the foredeck. The double bow roller is also substantial and well attached (for an AWB, I know they are lighweight Tupperware), and capable of providing an anchor point also( if I gave it a minute's thought).
At the back are the two outer cleats and the main winches.

I wonder how Shane Acton got on?
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It's not the number of cleats etc that matters, it's their size and how and what to they are attached the matters.

Shane Acton probably never gave much thought to it and if he did probably relied on the cork principal of just keeping it water tight and floating:rolleyes:
 
petehb said:
It's not the number of cleats etc that matters, it's their size and how and what to they are attached the matters.

Shane Acton probably never gave much thought to it and if he did probably relied on the cork principal of just keeping it water tight and floating:rolleyes:
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Hallelujah brother, and with a 1.2m draft, I will slip sideways easily.
I deliberately did not mention cleat size as this usually kickstarts an onrush of Tupperware assertions. If the chosen device rips the boat apart, then it seems you may as well adopt the cork principal.
However, if you have something that will stop you going 'quite' so fast and give back a modicum of control, that may be a good thing.
 
FullCircle said:
Thanks for all this information, but I am now wondering why Lalizas would market something that is so dangerous/useless? It seems similar in concept and design to the Jimmy Green item used in the PBO tests here.....

http://www.pbo.co.uk/gear/which-drogue-should-you-buy-25543

Lalizas also show this item requiring a 5x boat length piece of line, but the opinion here is getting on for 3 times that amount - say 60m (Lalizas) vs 150m (Forum) and 18mm or more, not to mention a huge para anchor to go with it, To be honest, I have nowhere to store such a device, and the budget for that would be North of £2000, and I don't have that either.

So, assuming that I am not going to be rounding Cape Horn (that's an analogy for those without humour), and I am no Moitessier, but may need to see out a good size mid atlantic blow, then are there any other recommendations?

Sorry to pee on my own bonfire, but should I just bin this idea?

PS I do have 5 litres of oil aboard.....
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You might invite Lalizas to respond. It would be interesting to hear their reasoning.
 
Just a quick 2p worth, not to hold a candle to the technical bumf above. I've sailed many miles trailing a drogue - they are wonderful for holding the stern firm to windward in big seas and allow you to make progress downwind in F7-9 under wind-vane steering with minimal visits on deck. A heavy, not floating line has to be best: it needs to get down below the wave action. I used 100m of 1" terylene line with a number of Jordan series type drogue cups (I never completed a full Jordan drogue) plus 3m of 8mm chain at the end. The chain was once bitten off, presumably by a shark.
 
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I think the OP has already mentioned that he has a fairly limited budget for this issue (haven't we all) so it is probably worth thinking about what you are trying to acheive.
If all that is wanted is a drogue to trail of the stern to slow the boat down somewhat and to give directional stability in big seas then that is a much different requirement to a parachute anchor set off the bows and designed to almost stop the boat.
Clearly the size of drogue the OP already has is neither - too big for a speed limiting drogue and too small for an effective parachute anchor.
If the aim is for a speed limiting drogue then a smaller drogue is needed - with an appropriate sized drogue the maximum drag is likley to be in the 300 to 500kg range although I don't think the OP mentioned the size of his boat (large boat means larger drag obviously). With loads in this sort of range the amount of stretch in the line is not much of an issue and the drogue will probably work just as well with a stretchy nylon line as with a more rigid polyester line or even non-stretch dyneema!!
If we accept that stretch is not that important and that we have a limited budget for something we hope not to use (or at least only need to use once or twice) then it makes more sense to use what is already on board. Most boats already carry a decent number of mooring lines that can be joined together to make a long enough line to trail a drogue, combined with a short length of chain and some shackles (lock the pins with cable ties) that should be enough to do the job. Any mooring lines on board should be more than strong enough to cope with the loads imposed by a drogue. Rig a couple of the mooring lines as a bridle if possible to improve directional stability and away you go.
This approach minimises the extra kit you have to buy and stow for very rare useage and you can have all the mooring lines already joined together well before you get into any bad weather and so just as ready to deploy as a dedicated line.
Obviously a parachute anchor is a completely different beast and will almost certainly require a dedicated line, but certainly not a collection of joined up mooring lines.
I would suggest that most people on trade wind ocean crossings will need a drogue much more often than a parachute anchor - in fact most will never need a parachute anchor. Given the usual budget constraints it is best to concentrate on having an effective solution for deploying a drogue. A Para anchor is nice to have if you can afford it but not essential.
 
I'm all for dual use components and one could extend crsjones suggestion. The OP will, surely, have a second anchor rode consisting of, say, 50m of nylon with chain attached. There is not going to be much use for it in mid-Atlantic and it could be used as part of crsjones suggestion.

Jonathan
 
thinwater said:
You might invite Lalizas to respond. It would be interesting to hear their reasoning.
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I had a dinghy made by Lalizas. It was the worst piece of junk I have ever had the misfortune to own. The rowlocks fell apart in the first day. A fish spine punctured the hull. With a 5hp engine fitted, the biggest recommended on the name plate, it would spew water over the transom. I hated that dinghy and would never buy any of their junk again. It was the only thing I could buy in Northern Spain when my rib was stolen a couple of years ago.
 
Neeves said:
I'm all for dual use components and one could extend crsjones suggestion. The OP will, surely, have a second anchor rode consisting of, say, 50m of nylon with chain attached. There is not going to be much use for it in mid-Atlantic and it could be used as part of crsjones suggestion.

Jonathan
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10m of 10mm chain with 70m of 18mm Anchorplait.
 
So this thread, it seems to me has reached an end. I am wiser in that consensus shows that what I have does not/will not work, and need to establish what does work.
I will open another thread where you can all give me your Adlard Coles Heavy Weather experiences and what equipment you carry.
I will probably limit this to those who have a boat similar to mine in length and carrying capacity.

Thanks to all the respondents, I value the contributions.
 
>So this thread, it seems to me has reached an end. I am wiser in that consensus shows that what I have does not/will not work, and need to establish what does work.

I'm not sure why you wrote that. Whether or not to use a para anchor or drogues depends on keel and fin configuration, details in my post. What size and length of rope is determined by boat weight, if you order either option the manufacturer will provide the correct rope size and length for your boat. The only issue is are you intending to go long didtance sailing? If not don't waste money on buying one of the options.
 
There are 2 reasons to carry drogues: bad weather, and emergency steering if the rudder gets jammed. I experienced the latter after hitting a submerged log. The former is probably more likely for most of us, and not having steering offshore is more of a drag then you think. This link gives some very good instructions. I've tried it like that in strong conditions, and it really works.

http://bermudarace.com/emergency-steering-drogue-new-approach/
 
KellysEye said:
>So this thread, it seems to me has reached an end. I am wiser in that consensus shows that what I have does not/will not work, and need to establish what does work.

I'm not sure why you wrote that. Whether or not to use a para anchor or drogues depends on keel and fin configuration, details in my post. What size and length of rope is determined by boat weight, if you order either option the manufacturer will provide the correct rope size and length for your boat. The only issue is are you intending to go long didtance sailing? If not don't waste money on buying one of the options.
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I wrote it because I asked what diameter and length of line to use. The thread veered off into a more general one of drogue and anchor design. I am advised by the wise that my plan was not wise, hence stopping it and starting a more general thread.
 
>I wrote it because I asked what diameter and length of line to use.

The only people who can determine the rope diameter and length are the manufacturers of para anchors and drogues after you give your boat weight , which I've said before. To find out call one of each or the one you would buy.
 
I disagree, KE. There does not have to be one definitive answer from the manufacturers. There are many degrees of freedom in the answer, including cruising area (likely wave and storm characteristics), crew strength and agility, storage space, deck equipment, and so on. Design and specifications are always a compromise as FC knows well.
 
>I disagree, KE. There does not have to be one definitive answer from the manufacturers. There are many degrees of freedom in the answer, including cruising area (likely wave and storm characteristics), crew strength and agility, storage space, deck equipment, and so on. Design and specifications are always a compromise as FC knows well.

When we ordered out para anchor the only thing we were asked was the weight of the boat, they are designed for all storms anywhere as are drogues. Storage, crew strength etc is down to the skipper.
 
Sarabande and Kelly: I think the answer, and having load tested many drogues, is half and half.

The load is determined as the maximum force that drogue can put on the line. For a parachute it is the wave impact force on the specific boat, for other drogues it is the force they generate at the maximum practical speed before they rip out. No one would design for any less than this maximum (for example, big waves not expected). There may be different drogue choices for different circumstances (perhaps that is what Sarabande meant), but the rode design matches the drogue, including weight added and length. It is part of it.

The load will be same for any drogue of the same diameter (or VERY close), so you can compare line strengths between makers.

The line should not be strained above about 12% of line strength. If it is, it will fail from fatigue. This has happened a few times, mostly with chutes. The ropes were too small. The reality is that for big storms and big boats, the conservative design number is pretty burly, larger than the anchor line.
 
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