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seriesdrogue or sea anchor

17K views 64 replies 21 participants last post by  SailNet Archive 
#1 ·
we have a 46 foot catamaran and are not sure what to buy. any recomendations and pros and cons ?
 
#2 ·
I think a Jordan Series Drogue is a better investment than a sea anchor. It will put less strain on the boat, and is probably one of the best pieces of safety gear for a small sailing craft...and 46' is still pretty small.

If you haven't read up on the Jordan Series Drogue, I'd recommend you go to the website, www.jordanseriesdrogue.com and take a look around.
 
#3 · (Edited)
I think they serve somewhat different functions. A drogue, deployed from the stern, is intended to slow a boat while sailing/running downwind and to prevent a broach / roll situation from developing when a large following sea engulfs the boat. A parachute 'anchor', deployed from the bow, is more of a way to "stop" the boat at sea during a storm. The Pardeys have written quite a bit on the subject. Their strategy in the use of the para-anchor involves heaving to, deploying the para-anchor, and then letting the boat drift very slowly downwind and, in the process, creating a 'slick' to windward of the boat that disturbs the surface tension of the water and inhibits the wave from breaking over the boat. The para-anchor is probably much harder to deploy and recover, but set correctly, it apparently allows you to retire below and get some rest. With a drogue deployed I think the boat has to be actively helmed.

I have a sea anchor and hope never to use it! I also have a drogue. Ditto.
 
#4 ·
Dawg...how does a multihull heave to? I don't mean technically...how well does it work without the same keel/rudder fources that a monohull has? Is lack of heaving to ability and resulting high stress on the boat via the sea anchor the the reason for your recommendation of drogue vs. sea anchor for a cat?
 
#5 ·
Billy-

The Jordan Series Drogue was designed to be a deploy and hunker down storm device for surviving the worst the sea can throw at you. Don Jordan, when I spoke with him prior to getting my JSD, compared it to an ejection seat on a plane, where you pulled the handle and then let it take over. Then, when the seas have calmed down... you haul the JSD back aboard and go on your way.

Cam-

Multihulls can heave to much like any sailboat. However, most multihulls are far safer if they retract their centerboards/daggerboards, since their ability to slip often helps prevent them from capsizing. The real problems with a parachute-type sea anchor apply to both multihulls and monohulls IMHO.

The problem with a sea anchor is that if it is properly sized, it will effectively stop the boat almost dead in the water—like an anchor would. The forces on the attachment points are incredibly high, much higher than those experienced by a Jordan Series Drogue, and few boats have hardpoints that are sufficient to the task.

Also, the way a parachute sea anchor loads up, is very different from that of a JSD. The parachute will suddenly fill and put a very high shock load on the boat and gear. Unlike a parachute-type sea anchor, a series drogue loads up gradually, as the boat moves forward on the wave crest and the drogue line straightens out.

The Series drogue is designed to slow a boat down to a very slow speed, and prevent the storm's forces from capsizing or damaging the boat. Since the boat is still moving, the waves, even breaking ones, don't get a chance to clobber the boat. Tests and real world experience has shown that the JSD will pull a boat through a breaking wave and prevent the wave from capsizing the boat. The boats generally don't even get pooped seriously, since the boat and the waves are moving at relatively close speeds.

Because of the design, a JSD can't collapse if the wave hits it wrong, like a parachute can. It also doesn't have to be a specific distance from boat like a parachute sea anchor does, simplifying its deployment.

Finally, the amount of rode you need for a parachute-type sea anchor is often bulkier than the JSD for the same size boat would be.

I hope this helps Cam.
 
#7 ·
Yup...that's how I feel too...so I got a JSD for my boat. :)
 
#9 · (Edited)
If you're in a lee shore situation, neither a parachute sea anchor or a Jordan Series Drogue is going to be the appropriate storm technique to be using.

You can get sizing info for a Jordan Series Drogue here. The sizing of the drogues is by displacement. What does your 46' catamaran displace???
 
#11 ·
You'll need to call them at Ace Sailmakers. They're a good bunch, and one of the few lofts that makes Jordan Series Drogues. The person I spoke to, IIRC, Dave, said that the bulk of their business has been taken over by the manufacture of series drogues. :)
 
#13 ·
Seajoy

I hope the replies you received here, are not the only research you've done on the subject. Most authorities and folks who have been in bad situations in catamarans seem to feel a sea-anchor is the way to go. You should obtain a copy of "Drag Device Data Base". This book has several hundred first-hand accounts from people who have actually used drouges & sea-anchors on all variety of boats.
I've never been in a life threatening storm, but as I understand, other than a well set anchor, the only device that may keep you off a lee shore, is a sea-anchor.
Marc
 
#14 · (Edited)
Be aware that the Drag Device Data Base was published in 1990, updated most recently in 2000 and due out with a new edition shortly. Also, the Drag Device Data Base may not be a reliable source of information, having a relationship to the Para-tech brand of parachute sea anchors. The books publisher is listed as: Para-Anchors International at Amazon.com. An excerpt from their website:

S/C-21: Vessel name Mutual Fun, Prout Catamaran, LOA 37' x BOA 16' x 6 Tons. Mutual Fun was hove-to to an 18-ft. dia. Para-Tech sea anchor in a whole gale about 450 nm NW of Bermuda in Force 9 conditions for about 15 hours. "Once the anchor deployed, it was like sailing into another world. No longer were we punching into the sea, but just riding over them.... We were able to say 'time out' during a severe situation." (Quoting her owner).

S/C-22: Vessel name Stress Relief, Catamaran, LOA 33' x BOA 14' x 6 Tons. Stress Relief used a 12-ft. Para-Tech sea anchor four times in heavy seas en route to Bermuda from Newport. Writes her owner: "First Time, 5-25-97: 48 hours on the sea anchor, seasick. Second time, 5-27-97: water inside the salon -- hung on the sea anchor until daylight. Third time, 5-30-97: radar fell off the mast & engine broke -- hung on the sea anchor until daylight. Fourth time, 5-31-97: genoa ripped during the night -- hung on the sea anchor until daylight."

S/C-23: Vessel name Laura Lee, Prout Catamaran, LOA 37' x BOA 16' x 6 Tons. Laura Lee used a 15-ft. dia. Para-Tech sea anchor to heave-to in a gale en route to the Canaries from Gibraltar. "It is very important to PRACTICE with this rig under windy but non-gale conditions as small mistakes could be disastrous under gale/storm conditions! We had a 'dress rehearsal' a few days earlier in Force 7 and learned the important lessons needed when the real thing caught us." (Quoting her owner).

S/C-24: Vessel name Dream Hunter, Kurt Hughes catamaran, LOA 45' x BOA 24' x 6 Tons. Dream Hunter used an 18-ft. dia. Para-Tech sea anchor to heave-to in a gale about 80 miles ENE of Punto Del Este, Uruguay. There being a current in the region, the cat was pulled 24 miles UPWIND (!) in the 36 hours that she was hove to. "Tendency to yaw was eliminated by lowering the boards halfway. No problems with deployment -- flaking the long rode is essential. Used rubber chafe guards. Once the sea anchor was deployed the ride was so smooth and controlled that crew of 3 slept for 12 hours!" (Quoting her owner).

S/C-25: Vessel name Kapal, Roger Simpson catamaran, LOA 42' x BOA 24' x 5 Tons. Two days out of St. Maarten, Kapal had a close encounter with Hurricane Jenny (November 1999) and her owners deployed an 18-ft. dia. Para-Tech sea anchor. Kapal was tethered to that sea anchor for 44 hours in winds of up to 60-knot winds. "We are very happy with the result and certainly very glad we didn't go through the eye of Jenny (30 nautical miles in diameter)."

S/C-26: Vessel name Sanyassa, Prout catamaran, LOA 35' x BOA 16' x 6 Tons. On her way to Fiji from New Zealand, Sanyassa ran into a nasty blow and her owner decided to deploy an 18-ft. dia. Para-Tech sea anchor. Difficulty was encountered in setting the sea anchor in those conditions, but "once the parachute was deployed all problems ceased," (to quote her owner). Sanayassa was sea-anchored for 24 hours in Force 7-8 conditions, her crew managing to get much-needed sleep.

S/C-27: Vessel name Mango Mi, Chris White catamaran, LOA 42' x BOA 23' x 7 Tons. Twenty-one days out of Mexico and 350 miles from Hawaii, Mango Mi found herself in confusing seas piled high by 28-35 knot trade winds blowing over the unlimited fetch of the Pacific. Suffering from fatigue and worried about the prospects of surfing down 15-20 foot seas at 17 knots, her crew decided to deploy an 18-ft. Para-Tech sea anchor, in their own words, "to park it and get some sleep." Deployment went off without a problem and soon Mango Mi was anchored to the surface of the sea, facing into the waves. "We lay at anchor for 20 hrs. and got some much needed rest. We drifted 8. 3 nm towards our destination." (Quoting her owners).

S/C-28: Vessel name Catapult, aluminum catamaran, LOA 40' x BOA 23' x 7. 5 Tons. Catapult was tethered to an 18-ft. dia. Para-Tech sea anchor for three days when her crew ran into adverse conditions in the Tasman Sea. "The wind did not ever get to a steady 40 but there were rather large seas as is commonly the case in the Tasman. The boat rode OK but I did not enjoy the motion and my crew and eventually I got sea sick." Difficulty was encountered in retrieval but the skipper came up with an idea: "I tied the boat end of the sea anchor line to a couple of large fenders and tossed it free so that the whole sea anchor rig and line were floating free. We then motored up to the trip line buoy…. The recovery from the moment of picking up the trip line buoy was a piece of cake."

S/T-22: Vessel name Friends, Walter Greene trimaran, LOA 35' x BOA 29' 6" x 3 Tons. Friends ran into a nasty blow with large and confused seas 60 miles off the New Jersey coast. Her skipper deployed a 15-ft. dia. Para-Tech sea anchor, but the 50-60' of nylon rode snapped almost immediately. It is difficult to ascertain what happened, but the relatively short 3-strand rope is suspect. 3-Strand nylon tries to unlay under extreme loading -- the "torque-wave" associated with extreme dynamic loads can create a hockle or local stress point, resulting in failure at that point. From the owner's report: "Rope was wrapped around Harken winches (3 times); rode went slack and tensed suddenly; rode snapped right near winch… the strands were somewhat fused together." The solution would be to use a no-torque braided nylon rode instead. See also illustrations on the Wave Rotation page of this website for a possible explanation.
I seriously doubt that the only brand of parachute sea anchor out there is a Para-Tech... yet that seems to be the emphasis of the site.
 
#15 · (Edited)
I'd also recommend reading this webpage, this page and this page. I'd also recommend reading this thread over at Cruiser's Forum.
 
#17 ·
Gershel-

I was merely pointing out that the Drag Device Data Base, both the book and website, may not be as objective and impartial a source of information, since they do have a relationship and presumably a financial interest in a parachute-type sea anchor manufacturer. Finanacially-motivated sources are rarely in the best interests of anyone but themselves and their wallets.
 
#18 ·
In a 46-foot catamaran, a sea anchor will put an awful lot of stress on whatever it's attached to. I've been told, and I tend to agree, that I would only use a sea anchor if the engines are out and the storm is blowing me toward shore. Otherwise, I'd use a drogue (or motor away from shore).

You can rig drogue with a Y harness so you can adjust the angle. I've tried it (on a Catana 52) and it's pretty stable even without the autopilot, with a bungee cord holding the wheel.

If you don't have a series drogue, you should make sure and put some chain ahead of the drogue for weight, and use a long rope, so the drogue doesn't fly out of the water between waves.

Think ahead on how you will retrieve the drogue (or sea anchor, for that matter). It will take some winching.

I haven't used either a sea anchor or a drogue in a storm. I've had a sea anchor on a Bahia 46, but don't have one now on a Catana 52. Had drogues on both boats. I have tried out drogues, but not a sea anchor, in wind.
 
#19 ·
Dawg, I'm not sure I see how you can deploy a drogue and then go below and get some rest, or even just chill out in the cockpit. Don't you still need to sail the boat? And ini the kind of conditions that require a drogue, I would think you would need to sail the boat quite actively.

Also, I think (but don't consider myself the expert) that a properly sized sea anchor shouldn't really stress boat fittings all that much (chafe is a much different story). The boat still moves with a sea anchor, you are using very long lengths of three-strand rode with a lot of stretch, and generally it seems to me that there will be give in every way conceivable. Surely the loads on the boat are less than if you were at actual anchor considering the additional rode and the designed sliding motion of the boat. In my experience, a sea anchor is best essentially when you are having trouble heaving to, for whatever reason (in our case we have a self-tending jib and with the mast stepped so far forward heaving to is not the easiest thing to do). Retrieving them is a pain in the stern to be sure, but that would be a small price if it allows you to ride out a storm more comfortably and safely. At least that's my view.

I don't have any experience with a drogue at all, but I would be very curious to hear how you use it in practice and not still have to sail the boat. I'm not criticizing the technique, just in case that's not clear.
 
#24 ·
No, you don't have to steer when using a properly sized Jordan Series Drogue. In fact, Don Jordan, when I spoke with him said, that would defeat the whole point of the device. It is designed to keep the boat from needing to be steered, and to allow the crew to get in out of the weather and get some rest.

There is a difference, despite what Sailaway says, between a sea anchor, which is supposed to effectively stop the boat, and a drogue, which is designed to slow, but not stop the boat. A lot of the confusion comes from the fact that some people do use the terms interchangably, and some people use a small diameter parachute as a drogue, but call it a sea anchor.

One major difference, sea anchors are generally deployed from the bow of a boat, and drogues are deployed from the stern. Another major difference is that the drogue is designed to let the boat run with the storm at a controlled, manageable speed, the sea anchor is designed to stop the boat head to wind, much as it would be if the boat were actually at anchor.

The problem with shock loading and sea anchors comes from the fact that the wave motion can cause the parachute sea anchor to partially collapse or for slack to build up in the rode. When the boat is then moved by a wave, when the parachute re-fills or the rode tightens up, there is a relatively large shock load on the mounting hardware. The JSD avoids this since the JSD is made up of many small cones...and as the load comes onto the JSD, the cones react gradually, starting with the ones closest to the boat and moving along the JSD until all of the small cones are fully expanded and under load.

As for how you use a JSD in a storm... generally the JSD is in a bag or locker. The JSD is essentially a long piece of rope with a lot of small cones sewn to it. At the terminal end of the JSD is a weight, about 15 lbs. in the case of my JSD, a bit more for a larger boat. At the boat end, the JSD is attached to a bridle that is attached to the outboard sides of the transom, and the bridle is about 2.5 times the distance between the attachment points.

To deploy it.. you dump the weight into the water, and let it and the drag on the cones pull the JSD overboard. You really have to take care to set this up properly, since once the cones are in the water, the JSD will tend to deploy itself very quickly and under a fairly significant load, with little opportunity to untangle it if it isn't feeding fairly.

When you've done that and checked the bridle to see that it is led fair and not chafing...you go down below and batten the hatches. :) Ride out the storm and then when it calms down, you have the PITA task of retreiving the drogue, which is not easy.
 
#20 ·
The two devices are designed to accomplish two completely seperate functions. In fact, a sea anchor deployed over the stern is commonly regarded as a drogue. The USCG uses the terms sea anchor and drogue interchangably.

I would second the notion on reading all the literature available, regardless of source. Much of it, inevitably, is going to be manufacturer sponsored. Why this should be a concern in essentially a life-saving device is beyond me. many of the smaller less capable sea anchors available specify "not for storm use" in their fine print. In such an obvious liability-ridden situation it's amazing that any sea-anchor manufacturer would comment in any fashion on their use.

I'd take exception to the idea that the loading on the sea anchor will be of the shock loading variety. The sea anchor is not going to pin you in one location, as with conventional ground tackle, and while the loads will be high, they will be more steady than imagined as the conditions that warrant deployment will already be sailing the boat excessively even under bare poles.

I'd probably prefer a drogue also if I was in a cat or a tri, given their propensity to pitchpole.
 
#21 · (Edited)
There's a lot to read on the subject and I've read a good bit of it. I've also had a parachute deployed on a 46' ketch in a mess of weather and sea outbound to Antigua from Morehead City in the Gulf Stream in 1971 - my observations were constant chafe issues and bending of the sampson post. The stresses are scary. The ketch also tended to skate around at anchor in a wind so she had a good bit of forward windage which added to difficulty of keeping her angled off (ala Lin/Larry Pardy.) After that experience and several less threatening experiences, we are fitting chainplates to our quarters to accomodate a JSD for our 33,000# 50' cutter. Spent a good bit of time talking to Para T and others prior to the decision.
 
#22 ·
It's also my understanding that one can have too large a sea-anchor, providing too much anchoring capability at the expense of strain and desirable leeway. I'd anticipate the need for beefing up a bollard or cleat as well. 15 tons of stress either by single part or bridle is a load no matter what.

Please let us know of your on-going experiences, Jim.
 
#25 ·
A sea anchor is big and essentially stops the boat. For a 46+ catamaran it seems like it would put a lot more stress on the boat than anchoring because the anchor chain's weight acts like a shock absorber in the waves. If a wave jerks the boat really hard, the anchor chain will straighten out and absorb a lot of the shock before it is fully tight.

This isn't true with a sea anchor on a rope. The sudden jerk of a breaking wave will be transmitted to the boat almost immediately because the rope or chain to the sea anchor is already tight. The wind and waves in a storm will put a lot more pressure on the boat than normally encountered at anchor.

Where is the strongest place to attach a sea anchor? cleats? windlass? winch? No matter where you put it, you should be able to let out a few inches of rope every so often so it will chafe in a new place. With either a drogue or a sea anchor, you can probably tie off the helm and go inside, or use the autopilot if it's available and can handle the conditions.

A drogue, because it is smaller, will have much less pressure, maybe by a factor of 10. That's why the boat moves. The purpose of the drogue is not to stop the boat. It's to prevent surfing so one of the hulls won't dig in at the trough of a wave. Also, with some forward motion a catamaran will ride on top of the waves better because the speed of the waves relative to the boat is less.
 
#28 ·
I don't see why not...they're basically on the same subject. :) And I wouldn't have to repeat myself... ;)
 
#29 ·
For what its worth I just bought a Para anchor, as for the sudden shock, 400
foot of 9/16" three strand nylon I would take up any shock loading, also the para vents at shock loads of 7000lbs.
 
#30 ·
Doesn't nylon have something like a 50% stretch value? If it is like a climbing rope the nylon will work like a big bungee, perfect!
 
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