Gone Floatabout

Sailing, Photography, Wilderness

Capsizing, why it happens, and how the Jordan Series Drogue helps

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Seth and I are grateful to have Ace Sailmakers and the Jordan Series Drogue supporting our voyage!  Ever since weathering a Force 11 storm off South Africa, we’ve wanted a series drogue on board, so we were very happy when Dave at Ace Sailmakers agreed to be a supporter.

Despite modern forecasts, ‘weather’—the sailors’ classically understated euphemism for a terrifying storm—is still a fact of life at sea. If you spend long enough traversing the world’s oceans, you’re bound to run into gales if not full blown Force 10 or above storms. Waves begin to break (think of surfing) in storm conditions, and boats can capsize or pitch-pole in breaking waves. Drogues, especially the Jordan Series Drogue, can prevent this.

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Yacht capsizes in a breaking wave, Image courtesy of Jordan Series Drogue

Yacht ‘Winston Churchill’ capsizes/pitch-poles in a breaking wave, Image courtesy of Jordan Series Drogue

Capsizing can occur when a boat turns broadside to a breaking wave: the boat rolls past her limit of positive stability, turns turtle, and (if she’s a ballasted monohull) comes back upright, usually without her mast which has snapped off because of the force of either capsizing or righting. Pitch-poling (essentially nose-diving) happens when a yacht reaches the wave’s velocity, accelerates down its face as it breaks, and crashes into the trough. Her stern comes right up and over her bow like a cyclist flying over his handlebars. Again she’ll lose her mast and the impact could cause major additional damage, including sinking, as happened to the wooden yacht Winston Churchill in the 1998 Sydney-Hobart Race. (Her demise was a combination pitch-pole/capsize: she hit the trough at an estimated 50mph at a 45° angle which tore off 8ft of her leeward planking.)

Drogue decelerating a yacht, Image courtesy of Jordan Series Drogue

Drogue decelerating a yacht, Image courtesy of Jordan Series Drogue

Drogues—drag devices set from the stern of a boat–help in two ways.  Correctly deployed, they keep a boat running with the waves, preventing her from turning broadside to them, thus preventing capsizing.  Equally important, they decelerate a boat before she reaches a wave’s trough, thus preventing pitch-poling and the kind of extreme force that spelled tragedy for Winston Churchill.

On our circumnavigation we experienced a Force 11 storm off South Africa’s Cape Agulhas, during which, to be honest, we should have deployed our drogue.  Thankfully we made it through unscathed aside from exhaustion and bruises.  Our drogue then was a traditional one consisting of 250ft of 3/4 inch line, at the end of which was a large parachute and a weight of chain and our small stern anchor.  While this would have helped, it would not have come close to the effectiveness of the Jordan Series Drogue.

Jordan Series drogue coiled for stowage, courtesy of Ace Sailmakers

Jordan Series drogue coiled for stowage, courtesy of Ace Sailmakers

Developed by aeronautical engineer, MIT lecturer, and sailor Don Jordan, the drogue consists of a series of cones woven into a tapering line, at whose end is again a weight of chain. It’s attached to the boat’s stern with a bridle. The number of cones and the length of the line is determined by your boat’s displacement. It works better than the single drag device because it has so many drag elements strung out along the submerged line. Don Jordan meticulously worked out the number of cones and their placement along the tow line through scale models, research at US Coast Guard facilities, and then testing in real breaking waves at the US Coast Guard’s motor lifeboat test site. Ace Sailmakers has maintained these high standards and in the 20 years the drogue has been in use, no boat has ever been damaged while using it.  There’s a ton more information on the Jordan Series Drogue website, about the engineering behind the device, wave science, and the case study of the Winston Churchill.

Seth and I will continue to analyze weather data and will continue our practice of subordinating any schedules or goals to storm avoidance. Nonetheless, as we set off across the Gulf of Alaska this summer, we’ll be comforted to know that we’re carrying an authentic Jordan Series Drogue, set up and ready for deployment at a moment’s notice!

Author: Ellen

Circumnavigator, Arctic voyager, writer/photographer

7 thoughts on “Capsizing, why it happens, and how the Jordan Series Drogue helps

  1. Me again Ellen! I presume you have got heating on your yacht for your big adventure? What do you have and recommend?
    PS it is freezing in New Zealand at the moment – hence my question!
    Thanks so much for your wise advice. Love your blog 🙂

    • So glad you like the blog! Yes, we’re going to have heating on this voyage, though we actually didn’t have it on our circumnavigation. Depending on the route you’re planning you might not really need it. We were pretty cold sailing down the East Coast of the USA on the first leg, but we also left Maine really late–October 31, after the first frosts and winter storms. We were again pretty cold in NZ towards the middle of May but it warmed up after the first three days on passage up to Fiji. So if you’re planning a mainly trade wind route, you might be able to do without. If you want to include Northern Europe or spend a spring or fall in New England or the Pacific Northwest, or if you’re planning a foray into the Roaring Forties, heating would be a good idea. Our boat already had a diesel Espar heater installed, and it seems to work well. It uses a lot of electricity though, and we don’t have much of that to spare, so we’re putting in a Refleks kerosene heater at the moment. It takes up quite a lot of space, but I’d rather have that than be unable to move my hands, etc. up in the Arctic 🙂
      Hope this helps!

  2. PS do you mind if I refer to your blog in my blog? I am collating all my research together in to one place on my blog and would like to include a link back to your thoughts. Thanks heaps 🙂
    Viki

    • Of course! That’d be great 🙂
      The Jeanneau is a pretty good boat, I think. I have a close friend who went around the world on an older 36ft Jeanneau (no fold-down transom) and he was happy with her. It did limit him to temperate and tropical waters, however–he had some troubles with his rig and didn’t want to put that to the test in the Roaring Forties… But I imagine your rig would be sound if it’s a newer boat. I hope Dave can answer your questions about the transom, and good luck with your preparations!
      Fair winds 🙂
      Ellen

  3. Hi there! Great to have found your blog and I look forward to following your adventures. We are also considering getting a series drogue, however the yacht we are looking at has a very flat transom and I wonder if perhaps a sea anchor might be a better option for us. I would be really interested to hear how you get on if you have to use it. Do you mind me asking where you got it from and a rough idea of price? The ones I have seen so far seem quite expensive!

    • Hi Viki, Glad to hear you’re enjoying the blog and thanks for subscribing!

      Regarding the Jordan Series Drogue, I don’t think a flat transom should be an obstacle to using it, though Dave at Ace Sailmakers would be able to tell you for sure. Their e-mail is: AceSailMakers@yahoo.com. (Please tell him we referred you!) What exactly is the boat you are interested in?

      Unless things have changed since 2008, you will have to have a sea anchor aboard to clear New Zealand CAT-1 regulations, but I’m not a great fan of sea anchors. Yachts are designed to drive forward through the water, so lying to a sea anchor is not ideal. In really big seas, especially breaking seas, the moving water will cause the line to slacken, rendering the anchor essentially useless. The yacht will yaw from side to side, potentially even turning broadside to the breaking wave before the line grows taut again and pulls her bow back around. The force on the boat is also in all the wrong places. Stern drag devices keep the yacht going the direction she’s supposed to; the line won’t slacken like that; and the force is where it should be. Of course, I haven’t yet used my series drogue, but the idea behind it seems sound: the large number of drag elements ensures that it will always have cones well submerged and doing their job! I won’t deny that they’re expensive (here’s the price list from Ace Sailmakers: http://www.jordanseriesdrogue.com/D_4_m1.htm, though it’s outdated by 2-400 dollars depending on your displacement), but compared to the price of a boat it’s pretty cheap insurance! And considering that these things might save you and your boat… I wouldn’t go to sea without a drogue!
      Best of luck on your preparations for your circumnavigation, and if you have any other questions, just ask!
      Cheers,
      Ellen

      • Thanks so much for your reply! You have got some good points there. I have checked out their website and looks great. Will drop Dave an email and see what he thinks about flat transoms. We are looking at a Jeanneau 379, which has got a lovely wide cockpit and transom that folds down to a swim platform, which I think will be lovely in calm weather, but not sure on how it will go when it is rough or if we are having to sit stern on to the waves! Thanks again and I look forward to following your adventures!

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