The Offshore Voyaging Reference Site

Large Sea Anchors, Not Recommended

Up until a some years ago we carried a 24-ft (7-m) diameter PARA-TECH sea anchor, and all the gear to set it, as our backup system. However, despite thinking that it was the best option at the time we bought it, we were never entirely happy with this solution, as I discussed in this chapter. So we got rid of our sea anchor for the following reasons:

Difficulty of Deployment

The deployment of so much heavy gear off the bow in storm conditions would be both difficult and dangerous.

Crew Discomfort

I believe that the pitching and yawing in true storm conditions would be truly horrendous. Most modern sailboats, particularly with the forward windage of roller furling headsails like Morgan’s Cloud has, yaw a lot at anchor when it is blowing hard; imagine the same behavior in 30 to 40 ft (9 to 12 m) seas! There are ways to ameliorate this, such as riding sails, but this is still more gear to rig and to break in survival conditions.

The yawing problem can be solved by using a Pardey Bridle but I have real reservations about rigging such a system on a boat the size of Morgan’s Cloud.

Retrieval Difficulties

I think that it is unlikely that Phyllis and I would be able to retrieve the sea anchor and its associated gear, particularly after being beaten up and exhausted by several days of lying to it in storm conditions.

I got an email from a friend who is a commercial fisherman running three draggers off the US east coast, that seems to confirm this fear. He says:

I have never needed to purchase a sea anchor. Towing a bottom trawl in the Gulf of Maine has routinely provided sea anchors of all types and shapes. Judging from what I have seen, people often discard the sea anchor rather than deal with its recovery.

Unrealistic Assumptions

The PARA-TECH manual, like that provided with the Galerider, demands that you deploy the drag device on a long rode so that it is immersed two to three waves away from the wave the boat is on and that the device is in the same relative point on its wave as the boat is on hers. Give me a break! Waves in storm conditions are confused and of varying heights and periods. They do not conform to the pretty diagrams in these manuals and, even if they did, how, pray tell, are you supposed to see through the blowing spray of storm conditions to where the thing is several waves to windward?

Shock Loads

A 24-ft (7 m) sea anchor, the size recommended for Morgan’s Cloud, is going to be essentially impossible to drag through the water. Being attached to something, in storm conditions at sea, that has almost no give, will generate forces that are truly frightening to think about.

The PARA-TECH manual calls for at least 600 ft (183 m) of nylon rope to ameliorate this problem. However, recent research shows that nylon rope that is being heavily cycle loaded, particularly when wet, is much more subject to failure than we all once thought. The problem lies with self heating, due to friction between the fibers, that can eventually lead to the rope failing through melting. I suspect that this may be the reason that many sea anchors are lost due to rode breakage, rather than the chafe that has usually been blamed.

Recently I spoke with a woman who had deployed a sea anchor on a trip to Bermuda. It worked well, but the nylon rope broke during recovery after the gale. This would suggest to me that it may have been weakened by the problem noted above.

Conclusion

So, while I’m not suggesting that sea anchors never work well nor discounting the fact that they have saved many lives and boats, I think there is now a better storm survival systems.

A Better Way

More on that in our Heavy Weather Tactics Online Book.

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Dennis Fechner

There is a major problem facing big boats (and small) in survival storms and the makers of parachutes are getting it all wrong when it comes to mono hulls in my opinion.

Parachute makers recommend a BIGGER chute if your boat won’t sit into the wind. This is like saying that if your boat shears around on your 45lb ground anchor, if you used a 75lb anchor you would shear around less. What nonsense. For a mono hull the only reason to use a chute is to slow the boat down WHILE YOU ARE HOVE-TO WITH SOME SAIL UP. To use a 24′ chute on your boat with no sail up would produce loads beyond reasonable. This is why it is so hard to find an example of a big modern boat using a big chute with success. Most have NO sail up and so they are just riding to the chute. Relying only on your line to relieve stress on a big boat does not work. Most break the line. WHY? They bought the chute Kool-Aid and are using it the wrong way, in my opinion. Most monohull sailboats should stay away from 24’ chutes. Big chutes are for Tris and Cats.

When you used your Galerider off the bow you proved that you do NOT need a big chute to slow the boat down. The biggest chute I would ever use is the small BUORD, which has flow through and so it relieves stress. Also, ANY bridle has to have a 30 degree angle coming back to the boat and that cannot be achieved using a snatch block on a boat much bigger than 30 feet! Which means you must attach the bridle line to the main line and not use a snatch block in boats much longer than 30 feet or so.

The BUORD would probably stop most sailboats dead in the water up to your size IF the boat is properly sitting hove-to with sail up. Its benefit over a Galerider would simply be that it may sit more directly up wind and add to the slick being formed. But maybe in a big boat like yours that is not necessary and the Galerider (a bigger one?) is enough.

I actually tried using my GP24 Seabrake on my Rival 32 to confirm what you found. In 30 knots my boat was sailing forward at 2.5 knots with two BIG reefs in the mainsail. That speed dropped to less than 1 knot using the Seabrake off the bow. And it rode just like your Galerider…up wind but off the stern. But it did help a lot with little effort expended! I have not had a chance to use it in higher wind and seas. Thanks for the idea.

That being said, I think the Jordan Series Drogue is far easier and safer to use on a BIG boat in a real storm and the fact that it has an almost perfect safety record makes it a first choice given enough sea room.

But if you don’t have enough sea room and can’t get it…the above is, in my opinion, the right way to use a chute on a mono hull…just like you used your Galerider but with a lot more power to stop the boat dead in the water so it drifts as dead downwind as possible…slowly. The drift rate will be about .75 knots and with a Series Drogue it will be about 1.5 to 2 knots dead downwind, so if sea room is the most important issue, the chute MAY give you twice the time till you hit land.

I applaud your out of the box thinking on using a Galerider off the bow…big payoff with little effort especially on a big boat. It may be all you need until you can’t hove-to any longer…interesting that that does not happen very often. Even in the Queen’s Day storm, so not likely for most of us in a life time of sailing.

Dennis Fechner

If the Galerider is all you needed that is fabulous! That was the whole point of my first reply…sailors must realize that mono hulls are NOT multi hulls which can use the big chutes.

I think the BUORD might be necessary for smaller boats because they are more easily rolled over but it would be great if some small boat owners would try using a Galerider or canvas Seabrake or Delta off the bow in a moderate gale. I will. I wish Larry (Pardey) would try it :-).

The loads imposed by the chute are what always made me nervous but I do think the small BUORD has enough give to it…it can be towed at 1.5 knots via engine behind a boat. (Try that with an 18’ Para-anchor.) This is what Larry Pardey keeps saying and on his bigger boat he actually went back to the SMALLER chute after the boat tacked in a storm.

The next time I need to wait out bad weather…which I hope is not too often…the spit fire jib will go onto the back stay (which works great at ground anchor and once when I tried it with the triple reefed main (60 sq feet). The boat was beam on to the seas until I put up the spitfire jib (25 sq feet) on the backstay…wow…it was almost perfect in a steady 35 knots with the bow at 45 to 50 degrees to the seas and the boat only moving slowly forward but not all the time). Then in will go the canvas Seabrake off the bow while properly hove-to with sail up. Having little forefoot and with the mast located at the forward station it may, or may not, keep the bow up.

You might be interested to know that in that other blow I took the spitfire jib down and put up the storm jib on the back stay (56 sq feet) and the boat started to sail backwards at times!! Most interesting, yes? So bigger was NOT better in that area either! The storm jib and the triple reefed main were about the same size…does not work…spitfire must be smaller…a bit less than 50% seems right to me. The boat did not heel any more with the spitfire up…it just pointed higher. It was sheeted in HARD to the base of the mast.

People need to experiment with their boats to learn how they will react BEFORE they really need to do so.

Dennis Fechner

Let’s beat a dead horse because details are so important…and it’s fun 🙂

Common thought is to use 10 to 15 times the boat length for the rode on a parachute. Seems reasonable…but what if it isn’t true? What if the design of a regular parachute is wrong for the application on a mono hull off the bow in a storm? That is my contention.

Even multi hulls have been rolled over from waves coming from a 45 degree angle off the main wave train when using 500 or 600 feet of line. They can’t adjust fast enough to the new wave angle.
In a major storm where Larry Pardey’s boat tacked, he had only about 200’ out on a 30’ boat. Larry did not think it was the short line but the too large BUORD…a 12 footer. So his answer, to me, is the correct one: use a smaller chute but make sure it is a flow through design.

Let’s go to Donald Jordan who says the problem of using a chute (solid kind) is that the orbital rotation of the waves and the stretch of the nylon line will cause the mono hull to sit beam on to the seas at some point and or leave slack in the line and be vulnerable to a roll over. This is exactly what happens. Plus the boat is pounded by seas when just sitting there.

If we then go to the military and NASA we see that all their designs require “CONSTANT rode tension” [a phrase used by Fiorentino Para Anchor Eds]…that is how a regular parachute works when moving through the air with something attached to it. No orbital rotation involved and constant rode tension. So why is it that the common belief is that you can use one on a boat in a fluid which has orbital rotation involved without maintaining constant rode tension?

The way Larry uses the chute comes much closer to overcoming this problem…the chute must be able to have flow through and be pulled through the water constantly for the bridle to work and he proves beyond doubt that it works, because only with a flow through chute can you maintain “constant rode tension”. And he can do this with a much shorter line than what is currently being prescribed for the ParaTech chutes. With a shorter line the boat does not have to move much for the chute to take effect from a wave coming from a different angle.

If we go back to the Series Drogue we see that “constant rode tension” (or close to it) is built into the system by the weight at the end of the drogue AND because the boat is constantly moving away from the drogue at 1.5 knots or so. And the drogue is designed to start working 1 second after a breaking wave strike and develop full power within something like 6 seconds. How long do you think a 500 or 600’ piece of 3-strand will take to adjust?

Using your Galerider off the bow worked for you but your boat was not fully stopped. If it were, would not the Galerider be riding more upwind instead of more off the back of the boat exactly as my Seabrake was riding while still moving slowly forward? But it must have slowed the boat enough for the slick formed to stay enough upwind to work for you with 200 to 250’ out, which is fabulous. I am not trying is dismiss at all what you did.

I still think on a smaller boat the BUORD may help to create an even larger slick to windward like Larry says it does.

But here is my main point and what I get from all I read…a regular parachute is not a properly designed item for a mono hull. It should be redesigned with more flow through SO that a shorter length of BRAIDED line can be used to eliminate some of the stretch in the line which causes the boat to end up beam on to the seas at times and makes the boat much more prone to waves coming from another direction. I also think that this better parachute will answer all your priorities, but ride more upwind to disturb more water for those boats that need it.

Donald Jordan has the right thinking and what I am trying to describe above is simply taking proper principles and placing them at the bow of the mono hull. A person may have to accept a bit faster rate of drift, perhaps 1 to 1.5 knots, to gain the advantages of a safer and more comfortable ride. My guess is that the chute need be no more than a true 6’ in diameter…and it can have variable venting for different boats. I know the way my Canvas Seabrake GP 24 is designed it distributes a lot more water around it than its 2’ diameter, so a 6 footer designed correctly might be very effective.

Next year if I have some money to throw away I plan on experimenting. All because of you, John, and your Galerider off the bow 🙂

The horse is dead…time to get to work.

[The link to Fiorentino Para Anchor and the quotation marks around the phrase “constant rode tension” were added 12th May 2013 at the request of Fiorentino Para Anchor who claim that their copyright protects said phrase; a claim that the editors of this site are not qualified to opine on. Nonetheless we are happy to make these changes in the spirit of amicable cooperation and to make sure all readers get a chance to read Fiorentino’s position and thoughts on this very important subject. To learn more about Fiorentino’s Rode Tension Theory check out this article.]

Greg Jerrell

Hello John,

Thanks for a great discussion. I’m a catamaran sailor with about 6000 miles worth of sailing. My wife and I are heading out in about a year. I’ve spent a great deal of time devising my bad weather plan and have concluded that a Jordan drogue and a parachute anchor with heavy duty bow constructed chain plates will be my strategy. In reviewing this article and the links I noticed you had an article in 2013 speaking negatively of large parachutes. I’m referencing the DDDB (Drag Device Data Base, by Victor Shane) as my factual basis for planning to use ‘chutes. My question is are you familiar with that study and the conclusions reached based on theoretical and actual real world case studies that conclude the ‘chutes are the best storm survival tactics under severe conditions. I appreciate your thoughts on this issue.