Drogues and sea anchors

Troutbridge

Troutbridge

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Being a bit lazy here, but anybody know of a chandlery that supplies these. I've done a quick search and so far all the 'off the peg' models seem a bit puny. Perhaps I need a 'bespoke' version. Anybody any ideas/experience (of sea anchors and drogues, before we wander too far off topic) /forums/images/graemlins/ooo.gif
 
This summers plan is to try one of those large sand/gravel sacks with built in handles that builders merchants use....

I'm working on the theory that if they can hold a couple of tons of sand, then they should be man enough for the job, and certainly as tough as anything i've seen advertised....

You can even get ones with a funnel/chute in the base... will try that alternative too...

All I need is to rig a tripping line to the centre to allow for a retrieval...

Gotta be worth a go!
 
The Drag Device Database by Victor Shane contains 120 firsthand accounts by offshore sailors who have used various drogues and sea anchors in anger. It gives systematically collected data stating type of boat, type of drogue or anchor, sea and wind conditions, etc. I think it was published in 1998 and is still in print.
 
Made a Jordan series drogue last year. It has 160 small parachutes. It was easy to make in front of the telly. You get the parachutes from Australia and splice them into braided line with a hook thingy. Didn't have to use it yet but nice to know its in the locker. Did the research and it seems to be the job for lightish displacement average white boats like mine.
 
your sand bag is possibly acceptable as a drogue. but lack of water flow through the bag will lead to lack of stability and probable bag collapse, then re-open, which would put a lot of strain on the system. It is also too small to have a lot of effect.

It is totally unsuitable for use from the bow. It would allow the boat to make so much sternway, there is a strong probability that you would damage the rudder.
 
Dumpy bags (which, BTW, hold 850 kg of sand etc.) are certainly strong but if they have sat for long in the sun they become very weak. I think you would be falling between two stools: they are too small to act as a sea anchor but, if you can get the mouth to stay open, would be far too big as a drogue.

For a boat of say 35 ft you would want a parachute of 10-12 ft dia or a drogue of 2-3 ft.

A few DIY stores do mini-dumpies of around the right size.
 
Jordan.jpg
CGabarit.jpg
 
Talbot,

I've got one that has an opening in the bottom, like a funnel, of about 12" diameter..... I figured that might be a bit more stable.....

Its worth a go....

Sure its maybe too small, but might be better than nothing.... or I may be able to put a pair in series.....

I'll play and see how I get on....
 
The one with the opening may have some effect (for example holding boat into current rather than wind if anchored, or suspending you into wind when not)I definitely would not add it to the bow for previous reasons, but may have some slight utility from the stern. If you do use it, make sure it is washed afterwards in fresh water and allowed to dry properly, or the next time it will just peel open.
 
This makes a change from the normal anchor thread.

Personally I wouldn't give a sea anchor/paranchor house room on a monohull. On my boat, the only way you could combat the stress on all the deck fittings, even if tied in series would be to take a turn round the hull or coachroof.

I inspected a Para-anchor this weekend and was surprised at how puny the shrouds were, mere 8mm braid on braid; especially when compared to how massive the main hawser. The eyelets weren't up to much either.

From more learnerd sources, Dumas, Motesssier, Hiscock et al, any attempt to stream them from the bow ensures that the boat rides at about 60 degrees to the wind at best, and more normally 90 to 120 degrees. The sternboard must risk the rudder.

Admittedly streamed over the stern they will stop you being pitchpoled (Wolfson Institute report) but the boat will be overwhelmed by seas breaking against her stern and threatening her companionway.

A small drogue, will control your down wind speed, but this can be achieved with warps (Robin Knox-Johnson in Suhaili), or a car tyre.

Warps laid on a long loop must easier to handle than any drogue device, Jordan series drogue accepted. The warp has more than one than one use, and an old car tyre comes at a popular price, free.
 
Car tyres do make excellent fenders - and if one is worried about black marks on the topsides, you can always make some nice fancy heavy duty covers for them.

And I would agree with Michael re streaming warps astern - this seemed to work well for RKJ and Suhaili, hence it should work well for most of us as well. If you want some extra drag, throw in a tyre (or perhaps an anchor attached to a fender?).
 
surprised to see a drogue made with laid rope - I thought plait or braid was the norm because of the mess that will result when it twists-up.
 
The term "sea anchor" as used in the days of Hiscock, Motessier et al, meant a small canvas cone. If streamed from the bow in a gale those devices were far too small to hold the bow into the wind and sea, and usually put the vessel beam-on to the seas, greatly increasing the risk of knockdown or capsize. The parachute sea anchor was unknown then to all but the multihull sailors and fishermen who began to experimenting with military surplus parachutes streamed from the bow. That proved so successful that monohull sailors, e.g. Larry Pardey, began to use them and purpose-made ones began to appear on the market. Today many sailors (see Earl Hinz's Heavy Weather Tactics: Using Sea Anchors and Drogues, 2nd edition, Adlard Coles or Paradise Cay) regard a parachute sea anchor as essential safety gear for offshore cruising. A parachute sea anchor that is properly made (see www.seaanchor.com) and deployed can hold a monohull or multihull with bow into wind and seas and reduce downwind drift to one or two knots in a gale. Most useful if you're 50 miles off a lee shore, or if you need to make repairs to rig or engine, or if your crew is exhausted. I wouldn't go offshore without a parachute sea anchor. Different boats behave differently. Mine didn't yaw more than 20 degrees either way during a 24-hour autumn gale off Norfolk VA. Other hull types, such as pilot cutters, or light finkeelers may require the use of a "Pardey bridle" to prevent excessive yawing.
Drogues streamed from the stern are quite different. I have no experience of them, but would feel unhappy about taking the seas on the weaker end of the boat rather than the stronger one.
As for the strength of the yacht's gear, find out the breaking strength of the rode you plan to use, then make sure your samson post or bow cleats, fairleads, bow roller etc. have strength to match. Chafe is a big problem, and a piece of chain in the rode is a good solution. You also need a strong swivel as well as proper splices, no knots.
 
The "one ton" builders bags with the "funnel" chute in the bottom work fine on a 34'er, 5½ tonne displacement mono. I have tried it both as a sea anchor and drogue (although only in an F8 so maybe not to reliable /forums/images/graemlins/grin.gif)

A stainless steel tubular ring keeps the mouth open but I found it was not needed. Try two loops of rope attached to opposite lifting points giving about 12' or more between the bag and the drag line - this should allow the bag to remain open sufficiently.
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