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**estarzinger** · 24-06-2010, 11:38

Quote:

Originally Posted by SaltyMonkey

The question is timing and size. It's a whole lot easier going forward in 50-60 kts than 70-90 kts on a 47 ft aluminum vs a 24 ft Dana in a confused cross sea.

We did also go round the world on a small (narrow and low free-board) 37'er and I felt the same (eg comfortable) about working on it's bow. That's the boat where I had to fix the furler in the gulf stream. And we used warps (off the stern) on the boat very successfully in storms.

At sea we have only ever seen 60kts sustained, and that probably only 3 times. We have see higher katabatic winds but that's a land effect and so not relevant to this discussion. We have see higher gusts in squall lines but that's also not really relevant to drogues and para-anchors. To see 90kts sustained you would have to make a really bad routing mistake with a hurricane. Honestly more that 40kts is very very rare.

A drogue is not an option.

Why Not? We know some boats that size that have used series drogues very successfully around south Georgia.

This is true, but again it's still a matter of strategy of when and how you will make your rounds and maintenance. Prepare early. Validate when you can, not because someone dictates a ridiculous maxim such as "You need to feel comfortable in all conditions".

OK, if you think its ridiculous that fine by me, but I suggest to people if they are going to be living on the ocean they should get comfortable with their environment - to me that only seems sensible. Like a rock climber is comfortable on the rock - still have some adrenaline but not be frozen into inaction.

SaltyMonkey · 24-06-2010, 12:04

High winds and sea - N atlantic crossing you might get a barrel full unexpectedly and not enough time to react. And of course there is the south australia NZ coast which can be unpredictable.

Quote:

Originally Posted by estarzinger

...I suggest to people if they are going to be living on the ocean they should get comfortable with their environment - to me that only seems sensible. Like a rock climber is comfortable on the rock - still have some adrenaline but not be frozen into inaction.

I have no problem with that.

Furlers - no one mentioned they had an engine and how to use that effectively in any of this. If you have one, you can possibly use it.

smackdaddy · 24-06-2010, 12:36

Heh-heh. There always seems to be a good fight going on regarding drogues and anchors. Had a good one on another forum.

My concern with the JSD was always the rudder. The force of the breaking water mentioned above as it slams into the transom/cockpit/hatchboards/etc. seems to be very powerful. I've just wondered...if the JSD is (after initial acceleration) holding the boat in place at about 1 knot as the wave "moves past" from stern to bow - what force is that putting on the rudder?

It was mentioned above that the most common problem with sea anchors was rudder damage due to "falling back" from either too stretchy a rode, or the anchor popping out of a wave face. Wouldn't the acceleration of breaking and sub-surface water cause the same forces with a JSD?

Look at this bad boy....galerider or JSD?

YouTube - Rough sea with freakwave

Hiracer · 24-06-2010, 12:54

Quote:

Originally Posted by smackdaddy

My concern with the JSD was always the rudder.

I think that is a valid concern. I've read about broken rudders with sea anchors, but never with a JSD. If there are some, let's hear about it.

The bungee effect with an elastic rode and sea anchor will happen on a regular basis in a storm, particularly if the boat swims at anchor. (This is perhaps part of the reason for the Pardey bridle.) But the danger to the rudder while using a JSD would occur infrequently, only with a wave strike large enough to pick up and drop her. So from a purely statistical perspective, I would image the risk is much less while riding to the JSD. This might explain why there aren't any reports of broken rudders with use of the JSD (that I'm aware of).

Quote:

Originally Posted by smackdaddy

Wouldn't the acceleration of breaking and sub-surface water cause the same forces with a JSD?]

Apparently not. I think the explanation is that the boat is moving much faster during a wave strike on a JSD than in the case of a sea anchor, so the speed differential between boat and wave is much less with the JSD. Less relative wave speed, ergo less force on the rudder. See my post #31 herein, and the link to the designer's comments.

SaltyMonkey · 24-06-2010, 12:57

And the problem with Pardey bridle is difficult to set and keep set. Then there is friction, chafe, and the like. Still, I'm a believer in this approach. Of course I don't want a spade rudder

Hiracer · 24-06-2010, 13:06

Quote:

Originally Posted by SaltyMonkey

Of course I don't want a spade rudder

I don't have a spade rudder either, but nevertheless in my view the non-spade rudder is more at risk of damage in the sea anchor context because it is totally unbalance, i.e., there's more force torquing it on account of its unbalanced design. Plus they tend to be barn door affairs, meaning wider and therefore a longer lever for the water to torque. A double whammy.

kb79 · 24-06-2010, 13:18

Quote:

in my view the non-spade rudder is more at risk of damage in the sea anchor context because it is totally unbalance

what about a balanced skeg rudder?

SaltyMonkey · 24-06-2010, 13:19

Wider? Longer? Bigger? Unbalanced? No i don't agree, and they have added support off the stern, unless they are barn doors like a IP or OI - that give me a concern

dana-tenacity · 24-06-2010, 13:24

Quote:

Originally Posted by SaltyMonkey

Good luck with that drogue trying to keep the boat stern-to on a cross or confused sea created by shifting winds on a fast moving or secondary lows. Good luck with an inexperienced crew when you have to perform rotating shifts to keep teams at peak concentration while aiming through the rogues.

Done it many times - no problem.

I'm thinking of weather that would have the crew (all of them) off the deck for safety reasons, you're not aiming anywhere, you are entirely passive, and if smart, down below, dry, well fed and in a bunk well protected from flying objects.

colemj · 24-06-2010, 13:33

Quote:

Originally Posted by smackdaddy

...if the JSD is (after initial acceleration) holding the boat in place at about 1 knot as the wave "moves past" from stern to bow - what force is that putting on the rudder?

I really shouldn't be in this discussion because I have no experience with these devices. But I have talked to a few people who have deployed a JSD (running before a storm bare poles) and they said they maintained 3-4kt of boat speed with the drogue. All said their autopilot handled it perfectly and the boat settled down nicely. They also said that they would see large following seas come up behind until they reached the drogue and split and go right around their boat, leaving them riding in a calm "slick".

Again, heresay - I don't have any personal experience. Maybe someone who has deployed one can comment?

Mark

Hiracer · 24-06-2010, 13:38

Quote:

Originally Posted by kb79

what about a balanced skeg rudder?

Better, IMO. But those usually don't have full sized skegs.

smackdaddy · 24-06-2010, 14:02

Quote:

Originally Posted by colemj

I really shouldn't be in this discussion because I have no experience with these devices. But I have talked to a few people who have deployed a JSD (running before a storm bare poles) and they said they maintained 3-4kt of boat speed with the drogue. All said their autopilot handled it perfectly and the boat settled down nicely. They also said that they would see large following seas come up behind until they reached the drogue and split and go right around their boat, leaving them riding in a calm "slick".

Again, heresay - I don't have any personal experience. Maybe someone who has deployed one can comment?

Mark

Personally, I'll take first-hand accounts any day over marketing material. Especially when that material (on the JSD website) starts chunking zingers like this:

Quote:

It is poignant to realize that every sailing vessel which went to sea from the time of the Romans had on board all the materials and skills needed to build a drogue which would have been capable of bringing the ship safely through a survival storm. They had strong hawsers used for anchoring, spare sail cloth for sail repair, and a sailmaker with the skill to fabricate the cones.

With the help of the drogue; St Paul on his biblical voyage across the Great Sea could have safely made passage to Rome instead of being shipwrecked in the wilderness, and the spread of Christianity would have taken a different course. The settlement of the American continents might have been advanced by 400 years if the Vikings had the drogue. Their vessels, although ideal for fast coastwise voyaging, were hopelessly unsafe on the open sea under storm conditions. Since they were undecked, they could not lie ahull without swamping, and if they tried to run off they would surf and plunge into the next wave. The Viking ships had no structural bulkheads and would have split open like a pea pod on impact with the green water in the preceding trough.

With the help of the drogue, the Vikings might have been able to support their colonies in the New World.

So much for conjecture!

The Vikings would have been Christian Sailors in Seattle WAY sooner with the JSD! Heh-heh. Priceless.

Quote:

Originally Posted by Hiracer

I think that is a valid concern. I've read about broken rudders with sea anchors, but never with a JSD. If there are some, let's hear about it.

The bungee effect with an elastic rode and sea anchor will happen on a regular basis in a storm, particularly if the boat swims at anchor. (This is perhaps part of the reason for the Pardey bridle.) But the danger to the rudder while using a JSD would occur infrequently, only with a wave strike large enough to pick up and drop her. So from a purely statistical perspective, I would image the risk is much less while riding to the JSD. This might explain why there aren't any reports of broken rudders with use of the JSD (that I'm aware of).

Apparently not. I think the explanation is that the boat is moving much faster during a wave strike on a JSD than in the case of a sea anchor, so the speed differential between boat and wave is much less with the JSD. Less relative wave speed, ergo less force on the rudder. See my post #31 herein, and the link to the designer's comments.

Yeah, I've not heard of or seen anything specific...and I've done a lot of research. But I see the wave in that video - and the power of it when it slams that ship...and I get the shivers. Serious power going on there.

All in all, I like the JSD. It seems like a great solution. Maybe it needs some better thinking on retrieval - but it seems to be good stuff.