Parachute sea anchor

[Mudisox]

What a long and argumentative thread.

I've read though the whole thread, amazingly without falling asleep.

All my experience can add, [and it has been in a variety of boats, yachts and ships in pretty appalling conditions of both wind and sea states, [5 hurricanes/typhoons and even the 87 'gale'] is that it is the sea state, that is important not the wind. You can mentally picture what the wind will do to your windage, and steady waves/swells are less of a problem than waves that come from all directions.

There is no one single answer to fit all. My own observation is that above 70 kts or so the wave tops are blown off as spume, and few waves will break.

My most hair raising and worrying time was in almost flat conditions passing between Ortac and Casquets when the Channel flood at Springs were met by the North going CI water. It felt that the boat went through 40-50 degree aspects in all direction as a response to irregular waves possibly standing waves. It only lasted 15 mins to crawl through under slow engines, but I can't imagine that a drogue/ parachute would have been of any use. Stupid I know but I now will avoid those areas on charts.

I have also hung onto parachutes and also streamed warps, but in different shapes of vessel. But one thing is for sure, length matters, despite what some might think. It allows stretch, and that helps to absorb the forces. 600m stretches more than 100m, note metres not feet. Recovery is not so much of a problem if you are not in a hurry and allow the seas / wind to calm down.

Back to bed then.

 

[VO5]

VO5, you haven't answered a single question that I asked. I asked them because I am interested. Perhaps I can be more clear:
- when did you try a Jordan Series Drogue?
- what was the boat, specifically (make, model, length etc or a description)?
- what were the wind and sea conditions?
- how was the JSD deployed? (length of warp, from which part or parts of the boat etc)?
- why was it deployed (what problem were you trying to address? e.g. going too fast and risk of pitchpoling? yawing and broaching?)?
- how did the boat respond to the deployment of the JSD?
- what specific problem did the JSD have that convinced you not to use one again (e.g. didn't slow the boat enough, kept pulling out of wave faces?)?

I'm genuinely interested.

I tried it about 6 years ago. I was not the skipper at the time, I was just invited to crew by a Belgian dentist friend. This was a Prout (38 ?) French Register. The voyage was outward bound from Cherbourg to first Vigo, then Lisbon, then the Med.

In the middle of the Bay of Biscay conditions began to worsen as a deep depression moved across. As I was not the skipper I did not take charge, I just kept my status as crew. Therefore the decisions were not mine.

Presently the skipper decided to deploy the JSD whilst having brought in nearly all sail except for a reduced genoa. I was very surprised that the JSD occupied such very small bulk.

The sea state was a force 7 gusting 8. But soon this worsened as a result of the wind backing. This whipped up a very lumpy sea with waves coming from two directions, a cross sea.

The cat did not like this at all and jumped about like a mad goat. The drogue seemed to slow her down but the movement was a lurching yawing / pitching during which the sterns of the boat slammed back into the sea.

I could see that the motion and ultimate direction was skewed. This made me very nervous as I could see either of the two bows burying themselves intermittently and either one or the other sterns lifting.

I prayed that we would not be pitchpoled.

I was assured by the skipper that the drogues were the correct number and size and the weighted end was suitable. But the vessel became more and more erratic, yawing about and pitching on one bow or the other, and not keepuing a heading.

The brace was a split brace fastened to the sterns of each of the floats and the angle at the crutch was I thought somewhat acute. But again I was told that for this rig this was normal.

The boat began to go like a train it seemed to me, much too fast.

As conditions worsened it was decided to shorten sail even further. But this did not stabilise her, because by now the seas were really confused, and all she did was slam horrendously. I have never had such a bad time.

Then after 7 hours the seas began to calm a bit and a steady swell developed with more regular wave forms that made for less scary movement.

But that night the wind and sea built up again. We were back to the original experience.

By 3pm the following day the sea was more manageable as the wind had dropped to a 5.

We then tried to recover it.

Phew ! What an ordeal. It would not go round the winch, so we had to heave it in by hand. Awful.

 

[Boo2]

That's just it, you see.
You refer to the experiences of others.
As I advise you in my previous post on this thread the best idea is for you to go out into the wide ocean, meet a howler, a real howler............. and try it.

The fact that I don't have any personal experience in a storm is a good reason for trying to discover the best way of staying safe if/when the worst should happen when I do gain that experience.

Your own avowed experience is 50kt winds and seas like "double deckers" ie around 15 feet. This is a strong gale with "high waves whose crests sometimes roll over" as you yourself described. People who have been out in worse than this report that single point drogues have the prominent drawback that they will be carried forwards by breaking waves.

You seem determined to avoid answering any points that are made to you. You dodge all issues about the inability of a rope to do anything but pull, and have remained completely silent about how a SeaBrake will behave when a wave carries it forward.

From your own reported experience I'm glad to hear that they work in moderately severe conditions, but your apparent determination to avoid responding to any substantive discussion make me think you must have some other reason for promoting them.

The big advantage of learning from other peoples' experience is that it must be broader than any single persons' and so more reliable generally. I think you should have the humility to accept that your own experience is only a single data point for other people to learn from and you should be more careful to avoid disuading people from alternatives that may be more suitable in more extreme conditions than you have experienced.

There are loads of reports of JSDs having been used to good effect like here for instance and a description of winching one back aboard in about 5 minutes at the bottom of this page.

The description of the Abbott drogue on this site makes clear the distinction between an easy to use drogue suitable for 50 kt winds and the JSD for use in survival conditions.

There is a comparison of the JSD and SeaBrake here where it is made clear that "total drag (Seabrake + oversize bridle) [is] very close to that of the JSD". But also note the paragraphs above where it says that "it needs some chain to help keep it in the water, though at these loads no practical amount of weight is going to take it down".

Finally, when there is conflicting advice and peoples experience differs it seems to me to make sense to give more weight to the opinions of people who understand some basic physics and less to those like yourself, who make stupid assertions which are obviously untrue.

I don't in any way rule out the use of a SeaBrake (or an Abbott or just plain warps) in a normal gale. However, from what I've read only a distributed drag device has any chance against breaking waves 25 meters high (5 or 6 double deckers) and even that seems optimistic with a JSD for a 10 meter yacht being only around 75 meters long.

Boo2

 

[Boo2]

The Seabrake exerts a downward force because once the drogue is deployed
it sinks, fast. As the Drogue is filled with water, it still remains submerged.
When it is towed it still remains submerged.
As the tow effort is increased it swells, but still remains submerged, the difference being that it adjusts to the tow, instead of not adjusting, which is why ordinary cones, tyres, and simple weights break surface.

There's a picture of a SeaBrake being towed at the link I posted above here which clearly shows the lip breaking the surface of the water.

Adding weights to the middle of the line will obviously have the effect of causing it to sink but tension in the line will counteract that.


Boo2

 

[Boo2]

It seems that no amount of explanation will suffice.

The problem is that your explanation is garbage.

Boo2

 

[JayBee]

The Seabrake has an interesting design feature which spills water at right angles to the direction of advance, creating a lot of turbulence. This technique is used in some commercial towing operations, where a twin screw tug with z-drive propellers (ASD), tasked with taking the way off a ship, may deliver more arresting power to the towrope by directing thrust outwards on each side, rather than directly against the tow.

The main (significant) argument against the Seabrake by JSD fans seems to be the possibility of the drogue being pulled or pushed out of the wave face of a following sea. This would be mitigated by adjusting the length of the warp to wave length, rather than boat length; a predisposition in favour of a lengthy adjustable bridle rather than a fixed length warp and bridle with eye splices just dropped over the cleats.

Interestingly, the Seabrake manufacturers specifically advise against running with the sea directly astern and recommend the drogue to be streamed from the “weather” quarter. Adjustable bridles would also allow the weight to be transferred from one quarter to another in response to changes in conditions and might help reduce any chafe in a fixed length system.

 

[Woodlouse]

This has become a long topic.

While the many advantages to using a drogue have been mentioned here repeatedly I still think a sea anchor has it's place and should not be overlooked. As I mentioned early on in this thread Heavy Weather Sailing currently leans towards sea anchors as preferable, and this opinion comes from experiences that are just as valid as VO5s.

It seems that if you get caught in heavy weather in a 13 ton 38 foot sloop then a Sea Brake drogue is your answer. It does not mean that it will produce the same result for a 6 ton tupperware cruiser or a 30 ton pilot cutter and to assume so is foolish.

I will say that I've never used either a sea anchor or a drogue, or any form of drag device for that matter. My storm tactic of choice is to heave to, and have not yet come across conditions where that was not enough. But my experience only extends as far as F10 and I don't often go to sea in light modern boats where this tactic isn't a valid option.

 

[Solent sailer]

Let us wait for Snowleopard to postulate his hypothesis and once he has done so, I will give you a full explanation. Let us just be patient.

does VO5 have a personal grudge with Snowlepard? the comments don't seem to add anything to the very interesting topic.

 

[robertj]

Having decided to possibly sail further afield after preparation of my boat, was set to purchase a sea anchor to help reduce the paranoid fear of getting caught out in a storm.
I am totally confused, this thread is akin to 'what boat is best?' as varying advice/experiences seem to get embroiled in the keyboard fusiliers resulting in the thread getting lost in arguments.

Please please please there are sailors like myself (though not inexperienced) do need help an advice and help choosing something that will possibly save their lives from more experienced and knowledgable folk.

Bob

 

[westernman]

Originally Posted by VO5
Misleading you say...

Aren't you funny ?

Then you go and contradict yourself throughout your post.

Incredible. It seems that no amount of explanation will suffice.

I saw nothing contradictory in Crisjones' post. It all seemed clear and logical to me. VO5 perhaps you would like to point out those contradictions to the rest of us who did not manage to spot them?

Sorry for repeating myself, by I did not see any answer from VO5. I really would like to understand where you think the contradictions are in Crisjones' post.

I am sure that almost all of the people reading this forum did not see any contradictions either - so please do enlighten us VO5.




__________________

 

[crisjones]

The thread does seem to have gone off track a bit, although drogues and para anchors are similar they are used in different ways to acheive different aims. The OP was asking about parachutes.

Early experiments with parachutes as sea anchors were done using ex-military parachutes - sometimes they worked, sometimes they didn't. The major flaw was they were simply not strong enough to cope with the forces involved in anchoring a boat in storm conditions - vastly different to floating a man or cargo down to earth in air. Hence parachute anchors (BORD) got a bad reputation for not doing the job properly, or failing at very dangerous times.

Modern sea anchors are purpose designed for use in water and will put up with the stresses and forces applied to them by a boat in a storm. However para anchors have one thing in common with drogues - they MUST be big enough for the boat and the conditions. A para anchor that is too small can be very dangerous because it will not hold the boat properly into the wind and seas, the bows may get blown off risking capsize or the boat may be thrown backwards quickly enough to damage rudders - neither scenario are what you want!!!.

For a detailed look at Drogues, Para Anchors and storm management have a look at www.maxingout.com/storm_management.htm. It is written by someone who has 11 years of cruising experience and is very informative - almost essential reading for anyone contemplating long distance cruising in a small boat.

The other factor with para anchors is you need a long warp, bullet proof attachment points and proper chafe protection at all connections. The long warp gives stretch and shock absorbtion to the system. A para anchor is not designed to move through the water, a drogue is specifiically designed to be towed through the water. The para anchor will drift with any current and it may move very slowly through the water, but for all practical purposes it is "anchored" in the water. Hence you must have a long, strong nylon warp to allow the boat to ride the seas without being subjected to horrendous snatching loads that would happen if you had no stretch in the system. The general consensus is that the longer the warp the better - 100m is probably the minimum.

Para anchors are generally rigged with a short length of chain at the chute to give enough weight to keep it down in the water - a flotation buoy is attached to the crown on a long line to make sure the para does not go too deep. Imagine if it went vertically down - it would be impossible to recover. The flotation buoy can also have a long floating line attached that you can use to "trip" the chute for recovery - some people reckon these trip lines can cause more trouble than they are worth because they can tangle in the warp.

For both drogues and para anchors the over-riding factor is that they must be big enough for the boat and conditions. It is probably true to say that neither can be too big but if they are too small you may as well not bother. A drogue that is too large will simply slow the boat a bit more than the correct sized one, not really a bad thing. A para that is too big will still anchor the boat.

Another thing to consider is what to use when??? This depends on many factors - sea room, weather forecast, crew strength etc. However you probably should consider the decision you make as a "one time" choice - if you opt for towing a drogue you are probably stuck with it until the weather abates. Imagine if the weather gets worse, you need to recover or cut away the drogue and then turn the boat around in storm conditions and then launch a para anchor - it does not bear thinking about!!! Same with a para anchor - once it is deployed you are not getting it back on board until the weather eases.

I have read many reports of para anchor and drogue deployment, you can find plenty of people who believe the use of one or other was instrumental in them surviving bad weather safely. You can also find people who will tell you the use of a drogue or para anchor made a bad situation much worse. What is very rarely said is wether the drogue or para that was deployed was big enough. Many of the failures may simply have been due to the equipment not being man enough for boat and conditions. Once again BIG is Best.

Finally there is the difference in application between the two - a drogue should be considered to be an "active" device, you still need to steer the boat because you are still moving - can your crew manage that for the forecast duration of the storm? A para anchor is a much more "passive" device, once deployed the boat should ride out the storm with little more intervention from the crew - indeed some reports describe crews going below, shutting the hatch and sitting it out, even sleeping and cooking!!!

As has been said before there is not ONE MAGIC solution that will deal with every situation, that is why we are skippers of our own boats - we have to make decisions after taking all factors into account. Everybody elses experiences are useful in helping us make those decisions, but it is ultimately YOUR decision - the skipper is ALWAYS responsible for the boat and crew.

 

[KellysEye]

>The thread does seem to have gone off track a bit, although drogues and para anchors are similar they are used in different ways to acheive different aims. The OP was asking about parachutes.

Excellent post, entirely agree. On sizing, we bought an 18 feet diameter Australian para anchor for a 14 ton steel boat. The site you mention is a must see.

 

[VO5]

does VO5 have a personal grudge with Snowlepard? the comments don't seem to add anything to the very interesting topic.

No, I do not bear any grudges against anybody.
Snowleopard made two posts on this thread which I considered a bit provocative. Then I invited him to present his hypothesis.
Result ? No response.
Why ? Simple.
He has by his own admission no experience on the subject.
He declares that he has had a sea anchor for 10 years, unused and is interested in being given advice.
As I don't bear him any animosity or grudge whatsoever, I am willing to help him gather knowledge.
I therefore recommend him to read "Tilicum".."The extraordinary voyage of Captain Voss".
This is available for free download.
In Captain Voss's account he will find a lot to learn and a lot to unlearn about sea anchors.


Today, 10:02
snowleopard
Registered User Join Date: May 2001
Location: Cornwall
Posts: 17,699



--------------------------------------------------------------------------------

There seem to be plenty of positive reports but I have come across statements that they don't work as advertised and I'd like to find some of those so I have an idea what can go wrong and maybe what can be done to put things right.

My interest is that I have had one sitting in a locker for 10 years and want to know what will happen if I ever have to use it in anger.
__________________
Preserve wildlife. Pickle a seahorse.

 

[snowleopard]

I therefore recommend him to read "Tilicum".."The extraordinary voyage of Captain Voss".
This is available for free download.
In Captain Voss's account he will find a lot to learn and a lot to unlearn about sea anchors.

And that is where we came in. What Voss used was nothing like what is now called a sea anchor. It was what is now called a drogue. I guess that's where this came from:

Is it easier to steer astern and go stern foremost and sustain the heading indefinitely

Which is what led me to believe VO5 doesn't understand the function of the device he is dismissing out of hand. The function of the para anchor is explained well in CJ's excellent post:

Finally there is the difference in application between the two - a drogue should be considered to be an "active" device, you still need to steer the boat because you are still moving - can your crew manage that for the forecast duration of the storm? A para anchor is a much more "passive" device, once deployed the boat should ride out the storm with little more intervention from the crew - indeed some reports describe crews going below, shutting the hatch and sitting it out, even sleeping and cooking!!!

And the reason I didn't reply before is that I don't indulge in willy waving contests. I shall now return to my own thread in the hope of a sensible discussion.

 

[VO5]

None of this is about willy waving, it is about common sense.

Furthermore it is about not expending unnecssary energy.

As the Seabrake dogue has several functions, one of these is to reduce rolling at an anchorage by hanging it from the end of the boomed out boom, so one sunny calm day in the open Atlantic in the Azores High, we decided to carry out a practical experiment...

Instead of deploying it from the stern we decided to deploy it from the bow, as if it were a para anchor. We brought down all sail...

The result was startling.

The water was very clear and we could look all the way down the tow and could see the drogue clearly.

What happened was this:

The drogue and chain fell vertically. To our surprise it began to be pulled by the current at an angle underneath the boat. There was no wind.

So we pulled it in. As we did so a very big fish followed it to the surface and swam away before it broke surface.

We came to the conclusion that streaming from the bow is pointless.

We then deployed it from the stern. The current began to tow it backwards gently. As there was no wind and the sea was dead flat, it didn't matter.

But we reasoned that if the wind arrived, ther drogue was already in the correct place to be efficient.

It is so obvious I cannot understand this persistence in clinging to outmoded ideas.

 

[Woodlouse]

Now that really does fail to make any sense. If there is no wind and the thing hangs vertically from the bow, there is no reason it would act differently if hung from the stern. You are right though, there is no point in hanging a drogue off the bow as it is designed only to slow you down. A Sea parachute is designed to all but stop you and far, far bigger.


You are doing yourself no favours by continuing to rant about your Sea Brake. Yes it is clearly effective. No it is clearly not the only logical choice. With this last post of yours I'm afraid you've descended into nonsense.

It is so obvious I cannot understand this persistence in clinging to outmoded ideas.

You are the only person who see's this. If you are right, then I suggest you take over updating and editing Heavy Weather Sailing because they seem to have reached rather different conclusions.

 

[westernman]

Misleading you say...

Aren't you funny ?

Then you go and contradict yourself throughout your post.

Incredible. It seems that no amount of explanation will suffice.

VO5, I have asked you several times to point out the contradictions in Chrisjones's post and you have not done so.

The only conclusion anyone can come to is that you are talking crap.

 

[Deleted member 36384]

.... If there is no wind and the thing hangs vertically from the bow, there is no reason it would act differently if hung from the stern .....

That is not what is said though. It's being implied, clearly from the VO5 text, that a device from the bow, can be pulled by the current in a direction towards the boat which is not favorable if you wish to have the device streaming out and away forward from the bow. Whether or not the observation in calm weather weather is valid or not for sever weather can not be determined just from the text.

The implication though is that hanging from a device where the current may pull it in a direction that you dont want, in heavy weather, is important and may be a reason for some descriptions of snatch loads on parachute anchors contributing to their ineffectivenss. Conversley a moving vessel with a device trailing from the stern will tend to maintain that device directly behind.

Later in his text it can be implied that this current carrying away the device astern is favourable for an early deployment in preparation for heavy weather of a stern bridled device.

This current effect could also be a reason for a bridle on a bow deployed device being used to align a vessel at an angle to the sea anchor. The bridle for a stern deployed device can do much the same if the bridle arm length can be adjusted.

I have read V05's points and I cant help feeling that he is being crucified because of his particular flamboyant and intransigent style of expression. So what, its a dumb ass forum of mixed ability contributors, not the definitive source of world expert opinion on seafaring skills.

I have gleaned, and continue to glean, a lot of information from this thread. Comparing this with Heavy Weather Sailing and Storm Tactics, amongst others, will be a worthwhile investment.

 

[VO5]

VO5, I have asked you several times to point out the contradictions in Chrisjones's post and you have not done so.

The only conclusion anyone can come to is that you are talking crap.

You remind me of some lawyer friends that I have, who just like to argue for the sake of arguing. Just read it and it will become obvious to you. I contribute to stimulate correct thinking but I am not prepared to do the thinking for you additionally. So get on with it.

 

[VO5]

Now that really does fail to make any sense. If there is no wind and the thing hangs vertically from the bow, there is no reason it would act differently if hung from the stern. You are right though, there is no point in hanging a drogue off the bow as it is designed only to slow you down. A Sea parachute is designed to all but stop you and far, far bigger.


You are doing yourself no favours by continuing to rant about your Sea Brake. Yes it is clearly effective. No it is clearly not the only logical choice. With this last post of yours I'm afraid you've descended into nonsense.



You are the only person who see's this. If you are right, then I suggest you take over updating and editing Heavy Weather Sailing because they seem to have reached rather different conclusions.

What are you on about ?
I have given an explanation that is very clear to help all of you have a realisation. But obviously the pennies are not dropping.

When a technology arrives that is superior and supercedes the previous, only Luddites cling to the old technology and try to destroy the new.

I cannot grasp why you lot do not understand it, because it is obvious.

It is so obvious, its screaming at you.