Heavy weather .. Lessons Learnt

Re: Parachute anchors

being far from an expert on Parachute anchors, I hestitate to offer an opinion. But I would have thought they'd really only be useful when

1)Sea is regular
2)Wind and waves are coming from the same direction
3) There's plent of sea room

<hr width=100% size=1>O wad some Power the giftie gie us
To see oursels as ithers see us!
 
Re: Parachute anchors

Well, the theory is as follows: the paranchor is deployed, and the ships leeward drift deploys it upwind of the ship. It shouldn't make any difference to deployment where the waves are coming from (remember that wind has a direction, waves msotly have an up and down motion, the waves travel but not the water) so they have no effect on the paranchor other than that of the recirculation of the water near the surface (name for that escapes me) - elsewhere AndrewB questioned whether the recirc may not tend to collapse the p/a.
Far from the sea being regular, the p/a should be deployed quite well below the surface, away from the recirc effects - this puts it steady in the water, balanced by the amount of drift it permits. A big question there is whether the resultant tugs on the rode will cause other problems.
Again, on number 3, the s/a is the one for when there is not much sea-room, since you stay anchored roughly to one spot. Contrast that with running off, that is when you will need plenty of sea-room.
According to Noel Dilly, who has a lot of exp., the best bet is to run off with a long series drogue. I don't like this idea, as it implies sea-room and getting pooped a lot.

<hr width=100% size=1>Black Sugar - the sweetest of all
 
Re: I suggest you

Well, I have read-learned-and-inwardly-digested LP's book and the Heavy Weather Sailing book plus loads of others, but this one has always escaped me - maybe a price thing? I will check. Ta.

I think your suggestions on the limits of heaving-to effectiveness should be tempered with what sort of boat. I would be happy h/t in F9, but haven't tried in higher simply cos I have always managed to avoid >F9. ( I am long keeler w keel-hung rudder). The fact that boats survive what the crew can't suggests that these lists of internal do's and don'ts are perhaps even more important than h/t, paranchor,drogues...

<hr width=100% size=1>Black Sugar - the sweetest of all
 
Para-gussets

Excellent, I see the generosity of your method now. She gets to avoid all the dangerous flying obstacles whilst you soldier bravely on. Once she's settled in position, I'd be inclined to empty any bottles below to minimise your personal risk of injury.

Would you organise any hand-signals, or do you think she'd be too busy keeping the tow from snatching to respond? I expect she'd be a little dizzy on her return- perhaps some water wings would stop her spinning the line too much? Still, she'd be keeping a beady eye on this wouldn't she?

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Drogues v para-anchors: sufficient searoom?

I suspect that the searoom required would be similar for both. Both devices rely on some downwind movement by the yacht to hold the anchor taut. It is possible to sail downwind with a series drogue, using the drogue to slow the yacht, but it doesn't have to be used like this.

I haven't seen anywhere an assessment of how fast one travels downwind with either of these devices rigged, no more than a steadying sail set, in big seas. If it is 2 knots then a day would mean 50 miles - the minimum to my mind of what comprises 'sufficient' searoom. Weather forecasts are now sufficiently reliable in most parts of the world to give sufficient warning to yachts within 50 miles of land to enable them to take cover. With prudence the risk of being caught on a lee shore is far less than it once was.

I am sure you must be right about the risk of pooping when using a series drogue to hold position. But the crew should be below, so the real question is whether the cockpit drains can cope.

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Re: Parachute anchors

I was thinking more of the efect on the boat of the wave direction, where you obviously want to be pointing into oncoming waves. eg Yu obviously would'nt want to be in a position lying to a sea anchor where the wind was coming from the north and large waves were coming from the east or west. I was under the impression the slick left by the leeward drift of the boat broke the waves before they hit the boat? The leeward drift of the boat seems therefore to be important. .. thus implying a lot of searoom

<hr width=100% size=1>O wad some Power the giftie gie us
To see oursels as ithers see us!
 
Re: Drogues v para-anchors: sufficient searoom?

What we really need to do, Andrew, is pick up on some of these winter gales and go out in your boat and try out the differences - no, second thoughts, I'll be your shoreside support, with your CG66 grasped in the fingers of one hand, something bracing in the other. :-)))

<hr width=100% size=1>Black Sugar - the sweetest of all
 
Re: Drogues v para-anchors: sufficient searoom?

Joking apart.. I think I read that the optimum speed to run off with a s.d is just below the speed of the waves? They seem to be faster than 2kts - I think there is a formula which someone can come up with relating the height of the wave to the wave velocity? Running slower would surely mean being hit by breaking waves more often, with consequent damage? I also read about the damage that these breaking waves can do - bending and twisting s/s pushpits.

As to the best attitude to the waves, the reserve buoyancy of the bow, with a sensible sheer, is considerably higher than the stern, so it will ride them better head on than stern on. That is not to say that I am disregarding the point the Pardeys make about getting the boat at an angle to prevent being thrown this way and that. An angle of 30-40deg seems to be suggested as optimal.

The Pardeys are not the only ones to push for the PA, there are many other instances, they are just the most vocal (commercial?) of those.

<hr width=100% size=1>Black Sugar - the sweetest of all
 
Re: Drogues v para-anchors: sufficient searoom?

Acshully DeeGee its your turn, I've tried out the SB butterchurn , the RNLI snowstorm ornament, the AVS of an AWB as well as the patience of Kim. So off ye go, I'll write it up for you upon your return!

<hr width=100% size=1>O wad some Power the giftie gie us
To see oursels as ithers see us!
 
Re: Drogues v para-anchors: sufficient searoom?

No probs, we're planning a January cruise. You're welcome to come as scientific observer, don't forget to bring your para-anchor. (I'll PM you further about this).

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SCAREy suggestion.

SCARE = Storm Conditions Anchoring or Running Experiment.

Well, I was thinking that we should organize an 'event' like your CBourg trip. But this one, instead of wimps suggesting "to go out in an F7+ is irresponsible" - we only go if the forecast is F7+.

Some boats would take their parachutes, some their series drogues and they could all come back and evaluate results. (Those not returning would be disqualified, of course).

Unfortunately, I would only get my PA or SD as the results of - so I would only be able to act as shore support - which of course, I would willingly volunteer (&=))

<hr width=100% size=1>Black Sugar - the sweetest of all
 
Sea room; aye, there\'s the rub...

For most of us, the biggest danger is always going to be the lee shore, not the survival storm. In any ordinary North European summer gale, I would infinitely prefer to heave to, as in such a case the boat should be making more or less of a square drift, with negligible leeway. I've argued before that a boat should be making way when hove to - not a lot, but maybe as much as a knot, to reduce the rudder loads, and indeed it is evident that most boats do this - else why lash the helm down?

I cannot see how either drag device can function at anything less than two knots; my one experiment with a warp and a tyre may have produced an even higher speed but it was pre-GPS and in my case pre-through hull log!

I think the danger of losing the rudder, if lying to any type of drag device from the bow, must be very great.

My boat is a very classical shape with highish bows, a long keel with rake down to the after end, and a counter stern. She really, really, does not like having her bows into the wind and sea, and I would esteem it folly to try to keep her so. I am for the warp out astern, ideally with series drogues on it. I've been pooped in this situation and it was not very alarming - but the boat has a tiny footwell with 30mm drains on it. A boat with a proper cockpit might be a very different proposition.

So, for me - anywhere on the continental shelf - heave to. In a mid-ocean survival storm - series drogue from the stern.

I think!

<hr width=100% size=1>Que scais-je?
 
Harness tethers

Interesting that one elasticated harness tether lost all its springiness. is this supposed to happen?

Also, would it be a good idea in these sorts of condits to be double hooked on - port and starboard. If the boat goes all tippy with the downhill side being the side you are clipped too, you are very likely to end up in the water, being towed along when the boat recovers. And getting back aboard in 12 foot seas could be a tad interesting. So would it be better to be hooked on uphil as well as downhill?

<hr width=100% size=1><A target="_blank" HREF=http://www.writeforweb.com/twister1>Let's Twist Again</A>
 
Re: Elasticated Harness tethers

I'd thought elasticated webbing safety lines are designed so that there is less trailing line to get snagged up and that the elasticity is not part of the safety functionality. However the guy thought that it was. ie there was sacrificial breaking to lessen shock loading.

<hr width=100% size=1>O wad some Power the giftie gie us
To see oursels as ithers see us!
 
Re: Heaving to

Definitely my first choice in any ordinary North European summer gale, up to certainly F9. I have hove-to in that sort of wind, admittedly in long keeled boats, but my experience stops at that point! The boat sits quieter, and you lose less ground to leeward.






<hr width=100% size=1>Que scais-je?
 
Re: Elasticated Harness tethers

I dont think so - the fall arresters have a length of webbing folded back on itself about 5 or 6 times, and stitched together - the stitching breaks progressively and reduces the impact.

The elasticated harnesses are just to reduce tangles as you say, and were I suspect simply over stretched - there is no way something so small can reduce the impact of a 15 stone body moving fast.

The best solution is to use short tethers (as required by ORC) when the going gets rough, unless you need the freedom to move. Peeps clipped on at 'workstations' (as the ORC/RORC) refer to them should only be on 1 metre tethers.

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