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Chastened
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Discussion Starter · #1 ·
This is a dumb question that I really should know the answer to by now, but...

A drogue (such as a delta drogue by Para-Tech) is towed from the stern, while running. The drogue slows the boat to a manageable speed, and provides stability. It can also be used to influence steering depending on how you attach it to the stern.

A sea anchor (looks like a parachute) is deployed from the bow, and basically parks the boat facing upwind. It also provides stability, especially if your boat doesn't heave-to very well. It prevents you from lying ahull and taking boarding waves and such.

Here's the question:

WHY would you want to lay facing upwind? Why wouldn't you always run off to escape a dangerous low pressure system, and use a drogue to safely control your exit from the area?

How do you decide if you should lay upwind to a sea anchor or sail downwind with a drogue?

Does it have to do with being pinned between a coast and the right front quadrant of the system, and being unable to run? (See Buys Ballot Law)

Thanks.
 

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I think we have enough experienced offshore sailors in the forum who can answer this question. It's a good question. I'll learn something, too.

That is a good link. Added to my files. Thank you.
 

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Chastened
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Discussion Starter · #4 ·
There are people on this forum have extensive blue-water sailing experience, that I have met PERSONALLY, that I do not consider hacks.

Auspicious (Dave)
Jackdale (Ok, haven't met him personally)
Jon Eisberg

I am actively seeking their knowledge and unique experiences on this topic.
I have been researching elsewhere, besides the forum, but of course you had no way to know that.

Thank you for basically calling me lazy and telling me that this forum isn't the appropriate place to ask the question. I disagree.
 

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This is a dumb question that I really should know the answer to by now, but...

A drogue (such as a delta drogue by Para-Tech) is towed from the stern, while running. The drogue slows the boat to a manageable speed, and provides stability. It can also be used to influence steering depending on how you attach it to the stern.

A sea anchor (looks like a parachute) is deployed from the bow, and basically parks the boat facing upwind. It also provides stability, especially if your boat doesn't heave-to very well. It prevents you from lying ahull and taking boarding waves and such.

Here's the question:

WHY would you want to lay facing upwind? Why wouldn't you always run off to escape a dangerous low pressure system, and use a drogue to safely control your exit from the area?

How do you decide if you should lay upwind to a sea anchor or sail downwind with a drogue?

Does it have to do with being pinned between a coast and the right front quadrant of the system, and being unable to run? (See Buys Ballot Law)

Thanks.
As always, It DEPENDS... :) Way too many variables in any particular situation to afford a simple answer...

Your supposition is right, however - I think the decision is generally based upon the amount of sea room available... One has to be pretty confident in the forecast, to consider running off towards a lee shore, no matter how distant... In the "Rallies Gone Wrong" thread, I've been arguing that's the big risk in sailing the rhumbline track that the Caribbean 1500 has historically favored - if any real weather out of the NE develops before you clear Cape Hatteras, the option of running off is not on the table...

Also, though it's not always the case, running off will generally tend to keep you in the weather longer, whereas 'staying put' to a sea anchor will often allow the system to pass over you more quickly... And, if your destination is to windward, and you've been fighting hard to battle upwind, it's not always a simple choice to give up hard-won ground to weather by turning tail and running off...

And of course, a lot will depend upon the boat itself... I'd have to think long and hard about lying to a drogue in big weather on a SenseBoat, for example :)






Rather than asking hacks (me too...) at an Internet forum, try perusing a fairly exhaustive research project on the subject. Read the anecdotal evidence and decide for yourself. In a nutshell, the variables are many, and no solution is absolute....

Victor Shane's Drag Device Data Base | Using Parachutes, Sea Anchors and Drogues to Cope with Heavy Weather ? Over 130 Documented Case Histories
Great resource... Glad I unloaded my $39.95 copy on eBay a few years ago, before Mr. Shane started giving it away for free...

:)
 

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Mermaid Hunter
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This is a dumb question that I really should know the answer to by now, but...
I was going to lead in with "there are no dumb questions" but, well, ...

This is a perfectly good question.

WHY would you want to lay facing upwind? Why wouldn't you always run off to escape a dangerous low pressure system, and use a drogue to safely control your exit from the area?
You have a good understanding of the roles and function of a drogue and a sea anchor. You have pretty much answered your own question.

We'll skip the fundamental question of what do you have on the boat. The next set of questions are: 1. where are you? 2. where is the weather system that is putting you at risk? and 3. where are the hazards you must avoid? Add to those an understanding of your boat and how it responds to various forces.

How much windage does the boat have? Where is the windage and how does it affect how the boat responds?

On your current boat, if you can run off a drogue makes tons of sense. If there is a land mass in the way then a sea anchor of some sort starts to look attractive. How much "storm stuff" do you have room for?

In today's world we have so much access to weather information there is little excuse for a conservative sailor to be caught by surprise by anything more than local weather.

There are people on this forum have extensive blue-water sailing experience, that I have met PERSONALLY, that I do not consider hacks.

Auspicious (Dave)
Jackdale (Ok, haven't met him personally)
Jon Eisberg
Thanks.
 

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Chastened
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Discussion Starter · #7 ·
This is exactly the kind of information that I was looking for.

I was recently gifted a Delta Drogue and was reading up on how to deploy it and that's where all the questions began percolating.

What Jon said about "being in the weather longer" is the exact opposite of what I thought would happen, so that's great info.

Do serious cruisers usually sail with each type of drag device or do they typically purchase just the one that fits most with their personal "heavy weather" philosophy? From a storage standpoint, I must say that the Delta Drogue is very compact and won't take much storage room at all.

As a coastal cruiser, I should be able to duck into safe harbor within 24 hours of a bad forecast, but some days I'm just not very smart. I could see myself making a mistake and being caught in something. :rolleyes:
 

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Thank you for basically calling me lazy and telling me that this forum isn't the appropriate place to ask the question. I disagree.
I'd appreciate it if you didn't put words in my mouth. I merely directed you to an authoritative source. Personally, I'd rather get answers from the best sources, myself.
 

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Like you, I was gifted a drogue (Seabrake). for the costal sailor who reads the weather forcast, basically useless. But I did a bunch of research because I was bored.

My fair weather testing of a number of devises, and how they apply to small/medium catamans.
Sail Delmarva: Drogue and Parachute Sea Anchor Testing: A Summary for Small to Medium Cruising Catamarans

Jordan's Coast Guard report. Very good.
http://www.jordanseriesdrogue.com/pdf/droguecoastguardreport.pdf

Sail Mag did a review in 2008. I plotted some of their data.

A long forum thread:
Cruisers & Sailing Forums

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I would add that as you read the data base, it is clear that incorrect deployment is the most frequent root cause of trouble.
* too short rode.
* no bridle. Turning effect is important
* wrong rode material (most drogues require polyester line, because nylon stretches too much, delaying action of drogue). Skipping chain when required (under load these things realy like to come to the top).
* poor procedure. Need to practice in poor weather. Run the engine to make certain the speed is realistic. Also, if you turn while deplying the rode will form and arc, absorbing impact.
 

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Most sloops,tied by the bow, tend to tack around the rode, or lie beam on to the swells. I have always ran my drogue from the stern quarter. Running it from the stern quarter lets the boat lie at slight angle to the wind, letting windage in the rig take the roll out of her. With the elimination of the tendency to lie beam on, or tack around the drogue, the loads and chafe are minimized, and thus the rate of drift. This also does the same riding to an anchor, in storms, in flat harbours. It is also much easier to deploy a drogue from the stern,and recover it. Using chain for the first few feet eliminates chafe altogether.
When one of my 36 footers recently cruised from Cape Horn to the Aleutians, she rode to a series drogue, off the stern, in extreme conditions, with no problems.

It would make a lot of sense for that "Senseboat" to have a closure for that open transom. Most do.
 

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I am glad i am not on that short list of experienced sailors... Because I have neither used my drogue or my parachute anchor!

BTW most people think a parachute anchor is a 6 or 8 foot diameter parachute... No, thats not what I'm on about. Mine is 18 feet in diameter on 100 meters of 1 inch nylon twist.

My preference is to my parachute anchor. Running off heads you into the low. And to be using it you would be in the Dangerous Quadrant, because if you were in the Navigable Quadrant you would be going hell for leather to get away from it.

A parachute works by stopping you dead in the water (examples of boats moving with the current not the wind) and it sets up a large area of slick water stopping, hopefully, waves breaking on you. Detractors say your boat moves backwards and your rudder breaks, but there seems no evidence if this.
 
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...
BTW most people think a parachute anchor is a 6 or 8 foot diameter parachute... No, thats not what I'm on about. Mine is 18 feet in diameter on 100 meters of 1 inch nylon twist.

A parachute works by stopping you dead in the water (examples of boats moving with the current not the wind) and it sets up a large area of slick water stopping, hopefully, waves breaking on you. Detractors say your boat moves backwards and your rudder breaks, but there seems no evidence if this.
You make a good point; a chute must be big enough to STOP the boat; they aren't stable if pulled through the water, and that's what drogues are for.

The reason they are generally deployed from the bow (always on multihulls) is that if you are stopped the waves are going to catch you, and bow-on is what boats are built for. But the chute must be big and the rudders should be stout. Risk of pitch poling is eliminated.
 

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That Drunk Guy
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I am glad i am not on that short list of experienced sailors... Because I have neither used my drogue or my parachute anchor!

BTW most people think a parachute anchor is a 6 or 8 foot diameter parachute... No, thats not what I'm on about. Mine is 18 feet in diameter on 100 meters of 1 inch nylon twist.

My preference is to my parachute anchor. Running off heads you into the low. And to be using it you would be in the Dangerous Quadrant, because if you were in the Navigable Quadrant you would be going hell for leather to get away from it.

A parachute works by stopping you dead in the water (examples of boats moving with the current not the wind) and it sets up a large area of slick water stopping, hopefully, waves breaking on you. Detractors say your boat moves backwards and your rudder breaks, but there seems no evidence if this.
Mark, I'm curious about your take on this. Would you deploy this broad off the bow so that you lay at a 45 degree angle? Or directly off the bow-dead ahead. And would you do this in addition to heaving to? or under bare poles?
 

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Since I got named.

I have never used a drogue or a sea anchor. I am rather anal about weather.

That being said.

I would use a drogue off a vessel that had little chance of being pooped / swamped. That would include double enders and canoe sterns that has sufficient flotation and small cockpits to avoid flooding with a breaking wave on the stern.

For modern boats with large cockpits and open sterns I would like the waves to break on the bow. The rudder is a huge issue, I recognize that; the objective is survival On multihulls I would rather that the waves break on the hulls. In either case, I would use some type of bridle to adjust the boat to waves and wind.


Sea anchors and drogues are usually employed under bare poles.
 

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I thought the is has been settled and the series drogue (long line with small parachutes along the length of it) was the best choice because it DOESN'T stop the boat suddenly but slows it down slowly as to not break anything and to let the boat not get beaten by the seas. And also, and I'm shooting from the hip here, don't most sailboats when riding bow into the seas with a a sea anchor tend to want to canter back and forth from Port to stbd. By that I mean due to the underwater profile of sailboats, they want to turn to one side of the seas and wind to the other.

I can imagine the stresses put on cleats, chocks, or whatever a huge parachute is tied to would be massive if the boat is being pushed down the backside of a wave and the parachute says no.
 

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Mark, I'm curious about your take on this. Would you deploy this broad off the bow so that you lay at a 45 degree angle? Or directly off the bow-dead ahead. And would you do this in addition to heaving to? or under bare poles?
Off the bow, dead ahead. Like a normal anchor...


 

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Mermaid Hunter
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Do serious cruisers usually sail with each type of drag device or do they typically purchase just the one that fits most with their personal "heavy weather" philosophy? From a storage standpoint, I must say that the Delta Drogue is very compact and won't take much storage room at all.
I think one or the other, or none, is most common. I don't carry either. Like jackdale I watch the weather very carefully using synoptics from weather fax onboard.

From those I know chafe and recovery are the two big concerns. Sea anchors in particular appear to lead to uncomfortable motion, are prone to chafe and to broken rodes, and are seriously challenging to retrieve. It is worth noting that sea anchors do not stop the boat. They slow it down a lot, more than drogues, but the boat will still be moving.

Credible sources indicate an hour or more of continuous grinding to recover either drag device after heavy weather passes. Think about what that means to you. Stories of people cutting away drag devices (expensive) are not uncommon.

I've given this a good deal of thought. For our plans I'm happy without a drag device. If I was going to cross the Pacific I would rethink that, adding dedicated chain plates on the quarters and carry a drogue, either a Gale Rider or a Jordon drogue from what is available today.

Risk of pitch poling is eliminated.
That is the point of a drogue - slow the boat, avoid burying the bow, maintain steerage, no pitch poling.

The USCG R&D Center in Groton CT recommends a drogue over a sea anchor.
 

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I thought the is has been settled
Apparently not. While it is probably the best survival tech for most boats in most storms, there are exceptions:
* Down wind drift is much faster (4 knots vs. 0.1 knots). This makes a difference if there is a lee shore or if running keeps you in the storm longer.
* Vulnerability of cockpit. Varies. Some boats shouldn't risk pooping, including many multihulls (big impact area).
* Weight. Towing a light multi up a wave is easier than a heavy boat.
* Sideways. Multis with the boards up or LAR keels have very little tendency to yaw under a sea anchor.
* Expense. JSD is pricy for those that don't foresee crossing oceans.
* Combersome. A drogue or chute is simpler in use for lesser storms.
* Stowage. Other drogues are smaller and lighter.

So I predict that chutes will remain quite popular for multis and drogues for coastal and occasional cruisers. They answer specific needs better.

I think Jordan did some amazing, outside the box work, BTW. Impressive.
 

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Since I got named.

I have never used a drogue or a sea anchor. I am rather anal about weather.

That being said.

I would use a drogue off a vessel that had little chance of being pooped / swamped. That would include double enders and canoe sterns that has sufficient flotation and small cockpits to avoid flooding with a breaking wave on the stern.

For modern boats with large cockpits and open sterns I would like the waves to break on the bow. The rudder is a huge issue, I recognize that; the objective is survival On multihulls I would rather that the waves break on the hulls. In either case, I would use some type of bridle to adjust the boat to waves and wind.


Sea anchors and drogues are usually employed under bare poles.

I'm reading and learning. I've never been in anything approaching true storm conditions, and hope I never will. But I'm curious about this advice. I've read elsewhere that modern hulls would likely do better using drag devices whereas more traditional design are likely better off hove to and then moving to a sea anchor. I've read that modern semi-planing hulls with solid spade rudders can maintain directional control much better than us full keel/transom hung rudder folk. Hence the choice of tactic.

Am I off base?


Why go fast, when you can go slow
 

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Long bridles.

Something I would love to see some work on is long bridles that are intended to function bot has bridle and as "towed warp." One great advantage of the JSD is that it functions both close astern to and far behind the boat; if a wave comes at a bad angle, the cones that are near have some effect, providing braking before any element towed far behind could feel it. This is a specific weakness of the parachutes. They are also less prone to a single point of failure (rode can still chafe).

What if we intentionally use a very long bridle, either all the way back to the drogue (no rode, per se) or at least 150 feet. This will be immersed and will present 2 lines in the water that would have to be forced sideways by any yaw. It serves as a towed warp, providing 20-50% additional drag (range based on testing--prior post)(note, a towed warp only provides material drag if it is a loop, which this is--the rode itself provides nearly zero drag and these speeds). It also reduced the elasticity of the rode (something drogue manufacturer specify) and provides redundancy (if the drogue fails, you still have the bridle, if one bridle leg fails, you still have the drogue). Steering and adjustability are also slightly enhanced.

Down sides are complications during deployment and additional warp. However, since these are now less specialized lines, I think many sailors might carry 2 x 150' lines aboard. As for deployment, the ability to brake all the way out might be nice. To recover, one would simply be cast off.
 
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