Parachute anchor v series drogue, plus engines?...

[tcm]

ocean trip coming up soo.... time to think about whether to use parachute anchor or series drogue, again. "Again" because for most if not all trips these things stay in the lazarette.

The parachute anchor goes over the bows, and then acts like an anchor, bows into waves.

The drogue slows dow n the boat and means when you run downwind or downwind ish the drogue stops the boat from falling too fast down wave fronts and/or broaching.

My own exp with this parachute anchor on another boat as practice in 20knots of wind was that the boat yawed about 40degrees each way so only used it once on that boat ...as obviously no flippin good ,,,to be effective the boat *has* to hold firm on para anchor with not much yawing at all - to ride clean over (or through, a bit, if breaking) the oncoming wave. Yawing even a bit like 10degrees risks the bow getting pushed off wavetop and whole boat then all ovr the place for next wave... prhaps falling/sailing sideways down back of previous wave and/or twanging up towards anchor, hence then lying possibly sideways in the trough, ready to get smashed broadside by the next wave. Which is no blimmin good.

Being a bit motorboaty, i have tackled biggish seas in 35ish knots off spanish coast but using two diesel engines to play around as sails a bit speculative in big wind - although steady setting allows a snooze, or might do....although probly not....

So i am thinking ...perhaps have a go with engine(s) as well as para/drogue?

None of the stormy stories seem to have tried this, it's engine off and rush around the deck ....when the real issue is to hold the orientation of the boat relative to next wave, and elsewhere (like frinstance in a marina) you might well adjust exact orientation of a boat using engine.

So how about with para anchor just run motors in gear at idle to hold the boat going dead astern pulling against parachute? I think i will have a practice and try this, cos the yawing is the big prob. It sounds as tho there would be loads of load but in fact there is plenty of slip around props etc...I think.

Drogue has different problems, aim being to run downwind slightly slower than the waves. At least this means apparent waves speed is slower and less crashity, although on stern. Again, i would have no problem running engines at idle ready for trimming stern up with engines, given drogue streamed well astern...

Note that boat in question is a cat, so praps better ability to manoevre with two engines. Not sure that the manoevrability extends to reversing up wave fronts (!) but quick jabs could be useful with a drogue, or gentle rumble with parachute...

Of course, i am game to try anything. All views welcome.

 

[Talbot]

For a cat, there is quite a lot of evidence that the series drogue is better provided you have the sea room, as it allows the boat to move with the wave rather better. However, and this is really the crux of the problem, the stern of the boat needs to be suitably designed to allow a breaking wave to crash onto the stern without busting through the door into the saloon, and draining fast enough to avoid any problems. A lot of modern cats dont meet this criteria. You also need to fit really substantial fittings for the bridle - as enormous loads are experienced.

The same is true up fwd for a parachute system - and the loads will be even higher. Furthermore, I would want to ensure that I had replacement storm boards for the forward windows.

 

[jwilson]

I have briefly motored to windward in very extreme conditions. It was brief as the engine then died. We had been inverted just before this. While the engine ran it worked well, and given plenty of engine power and fuel it would be my first choice in future. Deep sea fishing boats do this frequently. You need a LOT of power just to keep the bows up into wind

 

[bigwow]

Richard Woods was an advocate of drogues and parachute anchors until he had the misfortune to need to use one in anger. He now says they are a waste of money and totally ineffectual. Me never used one or even thought about buying one.

 

[PeterGibbs]

Two different problems:

1. to prevent the boat loosing ground in strong heading conditions

2. to prevent the boat racing ahead of its hull speed and being rolled by a following sea.

The Pardys are key exponents of the sea anchor forward with a bridle to slew the bow off the wind and induce a stable slow slide to leeward. This is criticised by others who reckon the bow will not lie as directed on their boats and will slam left and right with obvious consequences. The boat will also slam back on its rudder and could take damage. Otherwise there seem to be few protagonists of the "hold your ground" school.

When running, numerous sailors have trailed ropes etc to slow progress and maintain stability. I have tried this on a 42 ton steel sailing vessel with numerous warps in gale conditions, and the effect was minimal. Other much more illustrious sailors have had recourse to trailing warps and report a calming effect. No doubt connecting these warps to a sea anchor or drogue could assist, especially when the vessel is heavy.


I read few accounts of skippers using engines to increase stability in following conditions. Perhaps sailing is regarded in some quarters as the only response to high winds. I use this motor/sail approach myself and my boat is the more stable and predictable for it. But I confess I have not yet faced down Pacific rollers....

PWG

 

[Bajansailor]

As bigwow mentions, Richard Woods has had experience of of sea anchors - have a look at his website http://www.sailingcatamarans.com where he has written an excellent report about the conditions and circumstances that led to him abandoning Eclipse in a storm of Central America.
Click on 'Latest News'.

(BTW, Eclipse was later found a few months later, functioning as a floating bird colony, and happily drifting along more than 1,000 miles away from where she was abandoned)

 

[tcm]

well yes, excellent tho i suppose only insofar as the report essentially says throughout ..."don't do what we did"...

 

[Bajansailor]

Errrr yes, but isn't that one way that you chalk up experience, by occasionally learning what NOT to do, as well as what you should (or could) do.......?

 

[tcm]

well yes fair enuf.

There are other lessons from richard's experience tho, incl their decision to go offshore, the wrongness of boat (not) likley to capsize, the importance of rest/sleep which i think v important issue and i take his claim that in those circumstances with little sleep etc etc - very relevant for shorthanded crews instead of slightly larger crews...

... also the "mood" of the skipper and crew in a real emergency. This is most interesting. With richard for example his crew of 1 suggested epirb/mayday and as far as one can see from the text - he actually fell in with her decision, pretty much immediately. So none of that clipping on to not-easily-sinkable and still-quite-dry catamaran....he called in the cavalary, and (as it happens, and with massive benefit of hindsight) perhaps too early....the account shows that once they had made the mayday call the seas subsided, and of course as we know, the boat survived, upright.

I think they could have worked the boat until something more really did happen, instead of (as they did) richard feeling that something worse might happen.

Tho again, this all with benfit of hindsight and this is only a lesson learnt from richard's experience, not a comment against richard who is -it must be said - extremely generous to all of us to learn with his utterly frank account of his experience.

hence you're right re lessons learnt...

 

[Bajansailor]

I sort of get the impression that the decision to issue a mayday was primarily because of concern for Richard's crew who was relatively inexperienced - I am sure that if Richard had been singlehanded, or had his transatlantic crew (who must have similar multihull miles clocked up) on board instead, then he / they would have stayed with the vessel regardless.

Especially as she was not insured, and he had spent a couple of years building her himself, and she was most definitely his pride and joy, and quite rightly so - I went sailing on Eclipse one day when they were in Barbados a few years ago, and I thought she was one of the nicest sailing catamarans I have ever been on, with so many really excellent design ideas in abundance.

 

[silver-fox]

We each have to make our own decisions about how we are going to deal with heavy weather. From what experience I have the old adage of “the weakest part of the boat is the crew” certainly holds true.

I have been amazed at the hammering an AWB can take. I have also been horrified at the speed with which crews of healthy, fit, and experienced sailors can be reduced to near helpless morons, incapable of thinking straight, by fatigue brought on by prolonged exposure to extreme conditions.

IMHO the challenge is extreme weather is how best to protect the first the crew (which will fail first) AND then the boat.

Any pro-active solution requires the crew up in the cockpit, which may be OK if you have a full ocean racing crew, but is not so good if you are a typical husband and wife cruising combination.

Lying a hull or heaving-to will protect the crew but leave a yacht exposed to the effects of breaking waves because both these solutions cause the boat to adopt a near broadside stance to the weather.

I first came across my preferred solution, the Jordan Series Drogue, in Hal Roth’s book “How to sail around the World”

Don Jordan, a retired aeronautical engineer and keen sailor, developed the idea of a series drogue following the Fastnet race of ’79 and having proved it worked has made the design freely available for all to use which I think is a magnificent gesture.

Below is a link to the US Coastguard Report carry out tests in simulated laboratory conditions and then using their own boats. I think the report lays a few ghosts about what causes the damage and how best to prevent it.

http://www.jordanseriesdrogue.com/pdf/droguecoastguardreport.pdf

I have to confess that since making the decision, I have not had cause to deploy the drogue.

An inevitable conclusion from this report is that modern sailing yachts are far more stable tethered from the stern than from the bow. Don Jordan has come to the conclusion that in extreme conditions we should also lie to anchor from the stern.

Maybe in a few years time that will become the norm but I haven’t had the courage to try it yet!

 

[Bergman]

he idea of running the engine(s) with lengths of rope dangling over the blunt end seems to be a bit sort of counter intuitive.

I suppose the tension on the drogue should keep the rope well away from the props but I think I would worry a bit none the less.

Not sure what you gain with engines. I would expect windage on a catermerangue would be enough to provide forward drive for manoeuverability. Thought the idea was with the drogue you set the thing and then took to the bunk and prayed, shouted abuse at the crew or wept quietly - as the situation demanded.