Drogue or Sea Anchor?

Bill Roosa · Nov 27, 2016

Lots of differing opinions; sea anchors let the boat drift backward so the rudder going hard over and getting damaged and recovery of the chute are my objections on that, drogues let you run down wind which keeps you "in the weather" longer as you are running with it is my objection on the other. Both work to keep the boat safer in large waves. The time tested and captain approved method is to heave to and drip oil over the windward side but that can get really messy and I've never had the storage for that quantity of veg oil for that very low occurrence situation.
My advice is do your weather homework to pick your time, sail with a group and sail as fast as you can. There are lots of folks that sail for years and years and only see 40+ knot winds once or twice by "keeping a weather eye out". With that said I'd go with a drogue as busting the rudder is just adding to the danger in an already dangerous situation.

thinwater · Nov 27, 2016

I suggest reading the reviews in Practical Sailor (one this summer, another before long on emergency steering).
After doing the testing in conditions up to 40 knots, my preference would be for 2 standard speed limiting drogues rather than a chute or JSD.

Better for emergency steering (loosing steering is more common than survival storms). You can even go slightly to windward, really.
Much easier to rig and recover. Easier can be the difference in what is possible, since this can be heavy work in a gale.
In truly awful conditions, you can get practically same security and effect as the JSD by rigging them in tandem. Unlike tandem anchors, which suck, tandem drogues are a huge improvement, since they stabilize each other. This relates to the whole "rip out of the wave face" concern.

Gunni · Nov 28, 2016

I have no use for a sea anchor, but carry a Gale Rider Drogue. My thoughts are to keep sailing the boat until it will no longer sail or power. Once that happens, it is time to consider stepping off. Something to know is that a properly sized drogue will allow you to steer your boat even without a rudder. This works well.
A scenario far to common.

thinwater · Nov 28, 2016

Gunni said:
I have no use for a sea anchor, but carry a Gale Rider Drogue. My thoughts are to keep sailing the boat until it will no longer sail or power. Once that happens, it is time to consider stepping off. Something to know is that a properly sized drogue will allow you to steer your boat even without a rudder. This works well.
A scenario far to common.

I also tested this with the rudder purposely jammed to one side, since that has also happened in several high profile cases. It worked. But like all drogue techniques, you should practice ahead of time. It was actually kind of fun.

I actually went out in the 40-knot stuff on purpose, for testing. Several important lessons, not in the books (or rather wrong in the books) became obvious. I was surprised by that nearly all drogue and sea anchor "testing" is done in clam waters, which is entirely different. Just try throwing that drogue off the back, or adjusting an ill conceived bridle with over 1000 pounds of load.

All that said, they really do help. I'm convince that nearly all failures relate to either sizing (too small) or rigging errors (inadequate bridle, too short rode), based on my experiences and a review of case histories. In the case of sea anchors, I think folks forget that the safe working load of nylon is less than 10% of peak load, which are big in waves.

dziedzicmj · Nov 28, 2016

Read Surviving the Storm by Steve and Linda Dashew. It is widely available as a PDF (e.g. http://setsail.com/sts.pdf) or you can buy it on Amazon etc. They have a big part dedicated to various ways of slowing the boat down. And most of it from personal experience. Certainly worth a read.

Gunni · Nov 28, 2016

thinwater said:
Just try throwing that drogue off the back, or adjusting an ill conceived bridle with over 1000 pounds of load.

A drogue used for steering is a bit smaller, 30" in the case of the Swan, and I used the same size. The drogue control lines route to midships and then back to the primary winches which regularly and easily control these kind of loads. Once you get the drogue back to the stern it begins to break the surface and loses its grip.

thinwater said:
I think folks forget that the safe working load of nylon is less than 10% of peak load, which are big in waves.

I believe the swl is more like 20% of the breaking load.

As tough as a drogue can be, a sea anchor really loads up. I have a friend who deployed one and in the end cut it free to be clear of it. Could not recover it, even with the windlass.

DayDreamer41 · Nov 28, 2016

Great topic and one that led to a interesting read on testing of both a sea anchor and a drogue (actually a JSD drogue). After reading this article, http://www.yachtingworld.com/yachts...a-jordan-series-drogue-and-a-paraanchor-67260, I think I would be inclined to use a JSD drogue system, from the deployment and retrieval advantages as well as the apparent stresses imparted on the points where the apparatus is attached to the boat, it sounds like a better system.

thinwater · Nov 28, 2016

Gunni said:
I believe the swl is more like 20% of the breaking load.

And THAT is a common misconception that gets people in trouble. Under cyclical loading nylon will heat and fatigue very quickly at 20%. The chart says about 2000 cycles (green line), but does not include heating or chafe. The real answer is no more than 1000 cycles, which may not last the storm if you get a good load every minute or so. If you want to get over 20,000 cycles, you need to be at 10-12% BS. Additionally, the nylon heating myth is a result of lines that have been overloaded and would have failed anyway. In fact, any relatively new nylon line that is pulled to failure will show evidence of melting at rupture; it is an artifact of the great energy release.

The SWL calculations for nylon are VERY different from metals.

Look close and you will see that the ends are melted. One pull, no heating at all.

thinwater · Nov 28, 2016

DayDreamer41 said:
Great topic and one that led to a interesting read on testing of both a sea anchor and a drogue (actually a JSD drogue). After reading this article, http://www.yachtingworld.com/yachts...a-jordan-series-drogue-and-a-paraanchor-67260, I think I would be inclined to use a JSD drogue system, from the deployment and retrieval advantages as well as the apparent stresses imparted on the points where the apparatus is attached to the boat, it sounds like a better system.

This is why I have suggested using 2 drogues in series in severe whether. I am not the only person who has tried this, and so far, no drawbacks.

You can start with just one drogue and then add the second, under load, when things get worse.
Much easier to handle than any other system with similar drag.
Redundant.

The key is to have enough drag to hold the boat below about 4 knots, even in the peaks. If you go faster than that, the drogue WILL pull out of waves faces, and if you used a nylon rode (you should not have--drogues do NOT require stretch), it will snap forward. This is the advantage of multiple elements, like the JSD:

Enough drag to keep the speed below 4 knots.
At least 2 elements, so they aren't all on the wave face at the same time. It is the steep face they pull out of, like being anchored at short scope. During testing I was able to get single drogues of all types to pull out of the wave almost rhythmically, if over loaded.

Gunni · Nov 28, 2016

DayDreamer41 said:
I think I would be inclined to use a JSD drogue system, from the deployment and retrieval advantages as well as the apparent stresses imparted on the points where the apparatus is attached to the boat, it sounds like a better system.

With the Series Drogue system you have to carry the entire dedicated kit - all 300 feet of warp line with sewn on drogues. The gale rider folds into a small sack and uses your alternative anchor rode for deployment. Less gear.

Kings Gambit · Nov 28, 2016

Kiwi Puddle Jumper said:
Hi
I am new to the forum and would like to seek some advice from Beneteau 473 owners on their preference on sea anchors or Jordan series drogues for addressing severe weather. My preference is the Drogue but with the 473's ample stern it may cause difficulties. Have any forum members had experience streaming a Drogue in anger? We are delivering our 473 to NZ via the Atlantic and Pacific oceans early next year.

What is your planned route?

Pilgrimtex · Dec 19, 2016

I suggest reading "Storm Tactics" by Lin & Larry Pardey. I finally decided on a Fiorentino sea anchor. As for line; I purchased 300 ft of "pulling rope" from knotandrope.com. the construction is kernmantle and has a nylon core and polyester cover. It's basically the same as what Fiorentino sells.
You heave too and deploy your sea anchor with bridle rig and the boat produces a wake that keeps the waves from braking onto the boat.
The book goes into great detail. It's not boring and has a number of stories in it including the famous fast net race.
It helped me decide which to choose.

jssailem · Dec 20, 2016

for the JSD (Jordan Series Drogue)
http://jordanseriesdrogue.com

Pilgrimtex · Dec 20, 2016

If you're running with a drogue which slows you down you can be taking breaking waves into the cockpit. Tons of water sloshing around doesn't sound like fun. I've experience waves from the sides and stern and I'd prefer to take them quartered off the bow in a hove too position. The last storm we sailed through neither theory would have worked because of constant wind shifts and confused seas. Running the Yanmar at 3000 rpm produced only 3.5 knots at most.

Franklin · Dec 20, 2016

I carry a JSD, but I can tell you, you will not need it. The only dangerous part is the leg to NZ (assuming you do the typical coconut milk run and pick the proper departure dates) and for that you will just need to heave-to. This year the puddle jumpers just saw 25-30 knots but with big swell. I stayed in Tonga so I haven't heard the stories yet but I haven't heard of anybody doing anything other than heaving-to on that trip.

Drogue or Sea Anchor?

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SBO Weather and Forecasting Forum Jim & John

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