Heavy weather sailing

[rabbi]

Originally Posted by Cap Erict3

Jordan used to be open to questions. Ask him.

too late. He passed away some years ago


This weight thing just my own observation. I remember I read it somewhere when I initially did my research some years ago but have no clue where.
Bach then I played around with a few cones to check their quality, understand how it works and the variables involved and finally built a JSD for my previous cat before our first longer passages (ok, i was late and did it during the night watch of the first days). We used it only once in a non lifethreatening situation. It was just blowing some 35kn but we needed to slow down to avoid landfall at night. So we deployed the JSD (also to test it out in moderate conditions) and boat speed dropped to roughly 2kn. We could even turn off the autopilot as the JSD was taking care off.

We could feel the elasticity of the JSD, gradually increasing breaking force as more cones come into play. Everything was very smooth with absolutely no shock loads.

without the weight at the end the JSD would be stretched out all the time, with all cones sharing the load, no elasticity beyond stretch of the lines and the boat would be almost stationary due to the many cones. Also expect higher shock loads. IMO not what Jordan intended to do with the JSD.

[mikereed100]

Rabbi,
I think you are mistaken in regards to being able to adjust the speed of the boat while using a JSD by altering the amount of weight used in the anchor. The purpose of the weight at the end of the drogue is to simpy to keep the cones submerged. Jordan recommended 15-25 lbs. The CG paper mentions 25lbs for 'smaller' boats, 35-50lbs for 'larger' boats.

As long as the boat is moving, all of the cones are in play, regardless of the amount of caternary in the system. Increasing caternary by increasing the anchor weight may increase damping, but should not allow the boat to move faster through the water over time.

[rabbi]

Originally Posted by mikereed100

Rabbi,
I think you are mistaken in regards to being able to adjust the speed of the boat while using a JSD by altering the amount of weight used in the anchor. The purpose of the weight at the end of the drogue is to simpy to keep the cones submerged. Jordan recommended 15-25 lbs. The CG paper mentions 25lbs for 'smaller' boats, 35-50lbs for 'larger' boats.

As long as the boat is moving, all of the cones are in play, regardless of the amount of caternary in the system. Increasing caternary by increasing the anchor weight may increase damping, but should not allow the boat to move faster through the water over time.

Maybe i'm wrong, but this comes from my experiments and was confirmed on our single deployment. Since we were not in a serious situation but just used it to slow down i did some playing around before retrieving in the morning.
With boatspeed at 1.5-2kn the tail weight we used (20-25lb of chain) sank a significant portion of the JSD tail. Motoring full ahead just gave a marginal increase in speed but was enough to see the JSD stretch out a bit, bringing more cones into play. More if a wave was pushing us. you could see the effect by watching the line straighten, and the length of turbulence from those cones near the surface. When retrieving we reduced speed a little more by motoring in reverse and you could see a much shorter line of turbulence.
Maybe it was just a visual effect, or maybe we used too much or too little weight. But to me this makes sense. As mentioned a line of ~150 cones all actively causing drag would limit the stretch to the flex in the line. This was not the way it worked for us during the night, we felt like being tied to bungee cord in the sense that the boat would speed up a little and then be held back by bungee-like increasing forces on the JSD.

This is just my view and I'm certainly no expert on the subject. Afterall we used it for one night only and I slept like a baby most of the time. Everyone should trust their own gut feelings on this subject.

[Cap Erict3]

Originally Posted by rabbi

Maybe i'm wrong, but this comes from my experiments and was confirmed on our single deployment. Since we were not in a serious situation but just used it to slow down i did some playing around before retrieving in the morning.

With boatspeed at 1.5-2kn the tail weight we used (20-25lb of chain) sank a significant portion of the JSD tail. Motoring full ahead just gave a marginal increase in speed but was enough to see the JSD stretch out a bit, bringing more cones into play. More if a wave was pushing us. you could see the effect by watching the line straighten, and the length of turbulence from those cones near the surface. When retrieving we reduced speed a little more by motoring in reverse and you could see a much shorter line of turbulence.

Maybe it was just a visual effect, or maybe we used too much or too little weight. But to me this makes sense. As mentioned a line of ~150 cones all actively causing drag would limit the stretch to the flex in the line. This was not the way it worked for us during the night, we felt like being tied to bungee cord in the sense that the boat would speed up a little and then be held back by bungee-like increasing forces on the JSD.



This is just my view and I'm certainly no expert on the subject. Afterall we used it for one night only and I slept like a baby most of the time. Everyone should trust their own gut feelings on this subject.

From what I read in Jordan' documents, your experiences seem in line with his noted results.


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Looking for another pretty place to work on the boat.

[Cap Erict3]

Originally Posted by Cap Erict3

From what I read in Jordan' documents, your experiences seem in line with his noted results.


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Looking for another pretty place to work on the boat.

My earlier comment was intended to point out that a slight change in the chain weight was not likely to adversely effect drogues performance. In my opinion.

I have no experience with it, but think it likely the best choice between sea anchor, warps or other options.


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Looking for another pretty place to work on the boat.

[med]

Read post #3 in this thread:-

MULTIHULL DISASTER STORY FROM MED

Worth reading to understand how even an experienced sailor can make a fatal mistake.

The are some good lessons to learn from that accident.

[Mycroft]

Link didn't work for me med, is this the thread you meant?

http://www.cruisersforum.com/forums/...med-40329.html

Sadly the link to the original tale in the first post of that thread no longer works and I wasn't able to find a copy of it.

[med]

Post #3 here contains a lot of interesting detail:-

MULTIHULL DISASTER STORY FROM MED

The link keeps getting changed when I try and post it. No idea why.
Please put "multihulls4us" instead of "cruisersforum" in the above link.

[rabbi]

links to other forums like MH4US are not allowed (CF is a commercial site and not a hobby project for supporting sailing stuff).

With regards to the details, well there not much in regard to drogue device vs sea anchor. The sea anchor was deployed wrongly, was this the reason for the flip? Possibly yes, possibly not. Maybe the sea anchor just lost grip because it was torn out of the face of the next wave. We just don't know.

[med]

Originally Posted by rabbi

links to other forums like MH4US are not allowed (CF is a commercial site and not a hobby project for supporting sailing stuff).

Oops! I hope I don't get told off. Sorry guys!

[Mycroft]

Wow, riveting story! Amazing how bad decisions caused by fear and fatigue can compound.

[belizesailor]

Originally Posted by Swiftyacht

... I was previously a mono hull sailer but I think heaving to with a cat is somewhat different. Any comments on this subject most appreciated!

Originally Posted by monte

.... Option 2 - heave too, fore reach at low speeds to maintain postion and make the boat comfortable and safe. Option 3 - run with the wind and swell, lose ground but be comfortable.
We initially chose option 2 for the worst of it and were very comfortable fore reaching at 2-3 K. We were taking the swell at a slight angle to the bow, not enough to worry about sliding sideways down the waves and not too little that the bows would slam off the wavetops. Just a small amount of jib out and the helm lashed over. This worked very well and would have easily handled worse conditions so we were confident we had a good approach and back up plan for similar or worse future conditions...

Swifty, As you can see from Monte's post, heaving-to is a viable strategy for cats too. Every boat behaves differently though, so best to know before you go by practicing heaving-to in that particular boat. Whether mono or cat is not the biggest factor in heave-to behavior.

Heaving-to, mono or cat, is my prefered option too provided it is appropriate for the situation.

The basic technique for heaving-to in a cat is no different than a mono, but may need to be tweaked to adjust for characteristics of a given boat. I think there are threads here discussing this too.

Ive hove-to in squalls w gusts to 80 knots in cat and rode out sustained hurricane strength (Cat I) conditions in a mono. I hope those remain my lifetime records.

Ive sailed cats and monos with sea anchors & drogues aboard, and have deployed both for training/testing, but never used either out of necessity. Though I do feel more comfortable having a drogue aboard a cat/tri in the event speed control becomes necessary.

Ive experimented with using fixed props as drag devices, which another post mentions, on a cat. Both just locked and in slow reverse. It has some effect, but not like a drogue. I did not like the response of the boat in slow reverse...seemed to make it less directionally stable...not a good thing when surfing.

[arsenelupiga]

Originally Posted by med

Read post #3 in this thread:-

MULTIHULL DISASTER STORY FROM MED

Worth reading to understand how even an experienced sailor can make a fatal mistake.

The are some good lessons to learn from that accident.

if they were able to tie near headstay, they could use extra rope and retie to other bow.

seem like basic thing.

maybe they too exhausted, however, that is not excuse.

[med]

Originally Posted by rabbi

links to other forums like MH4US are not allowed (CF is a commercial site and not a hobby project for supporting sailing stuff).

With regards to the details, well there not much in regard to drogue device vs sea anchor. The sea anchor was deployed wrongly, was this the reason for the flip? Possibly yes, possibly not. Maybe the sea anchor just lost grip because it was torn out of the face of the next wave. We just don't know.

Indeed there are no ready packaged answers for you.
However, I feel it is worth reading to understand some of the things which are involved and which can go wrong.

[arsenelupiga]

Originally Posted by rabbi

links to other forums like MH4US are not allowed (CF is a commercial site and not a hobby project for supporting sailing stuff).

With regards to the details, well there not much in regard to drogue device vs sea anchor. The sea anchor was deployed wrongly, was this the reason for the flip? Possibly yes, possibly not. Maybe the sea anchor just lost grip because it was torn out of the face of the next wave. We just don't know.

i have mooring with 3 attachments (third - middle one, just in case) . Once I had to stop mooring process as wind suddenly increased with hail with boat attached on port bow and middle cleat only. Rotation of the boat was significant as not balanced. This could easily be reason for structural failure as boat sometimes faced beam on wind/wave. See no reason parachute would be any different, except much larger waves that can hit when boat beam on.