Tuesday, April 15, 2008

Heavy Weather Gear and Strategies #13—Drogue Retrieval, an Alternative from Hal Roth

posted by John & Phyllis Web Site

The last two posts in the series, in which we wrote about our solution for the retrieval of our Jordan Series Drogue, drew an interesting e-mail from Hal Roth, who did not like our solution because of the loads involved.

He was kind enough to share an excerpt from his upcoming book, to be published by International Marine in May, detailing the problems our mutual friends Willem and Corri Stein had retrieving a Jordan Drogue in the Southern Ocean (the event that inspired our own testing) and outlining his own retrieval idea. With Hal’s kind permission we are reproducing it below:

“At the end of the day, the Steins, tired from steering and the violent motion, deployed their Jordan series drogue which had 150 small cones sewn along a one-inch polyester line 400 feet long with a 22-pound block of lead at the end. As soon as the drogue was out, Terra Nova's speed dropped to two knots, and she kept her stern nicely into the seas. Life became tolerable and allowed the crew to sleep.

"The next day the wind abated a bit, but the strain on the drogue was still too much to even think about getting it back on board," said Willem.
There was a new problem. Due to the heavy pitching of the boat in the seaway, the bridle lines tangled around the water blade of the Aries wind vane gear. The Steins hoisted a storm jib which put more force on the drogue lines and kept them free of the water blade.

When the wind eased, the Steins tried to haul the drogue on board, but the task seemed impossible. "Even getting it around one of the sheet winches was such a dangerous exercise that I gave up after I nearly got one of my hands amputated," said Willem.
The Steins might have been able to use their engine to back down a little on the drogue while they pulled it in, but the engine was out of order because water had run into the fuel tank during the knockdown a few days earlier.

Willem and Corri waited two more days for the sea to calm down.
Finally in desperation they cut the lines to the drogue. I've sailed with Willem and Corri in Newfoundland and know they are tough, dedicated, experienced small-boat sailors. It must have been a hard decision to cut away the drogue which they had made with so much effort.

After thinking about this problem, I wonder if the following might be a solution? Run a 1/2-inch diameter recovery line from the anchor windlass at the bow outside the lifelines and back to the stern. Loosen one of the bridle lines (hitch on a short line and take it to a winch to pull some slack in the bridle line so you can disconnect the shackle from the chainplate) and attach the recovery line. Then let go the other bridle line. Now with the stern no longer fastened to the drogue, the boat should swing around 180° and drift downwind
from the drogue, bridle, and recovery line. You will have to pay attention to the lead of these lines at the bow, but it should be possible to pull them straight in with the powerful windlass, whether it's operated by hand, an electric motor, or hydraulic power. I've never attempted this with a series drogue, but I think it or some variation is worth a trial.


Anything to save fingers! Note that this scheme moves the recovery effort away from complications of a line around a spade rudder or the water components of a wind vane steering device. Additionally, the recovery effort at the bow eliminates problems of winching in the line in the cockpit with complications from the stern pulpit and other cockpit or transom gear.

In spite of these reports, other users of drogues write of simply pulling in the line by hand with no apparent difficulties. Obviously the recovery of drogues needs more investigation."


We think Hal’s idea makes a lot of sense although we would probably stick with our own plan, at least initially, since it keeps the operation in the security of the cockpit and does not require a turn into the wind and seas.

Another thought is that if we did try Hal’s method we would hoist our triple reefed mainsail or storm trysail before making the turn. This would allow the boat to lie heaved-to and keep her steady while we retrieved the drogue over the bow. This would be much like our technique for stopping wave strikes when heaved-to.

Earlier Posts in the Series
#1 Goals
#2 Heaving-To
#3 When Heaving-to is Dangerous
#4 Options When Heaving-to is Not Working
#5 Stopping Wave Strikes While Heaved-To
#6 Survival Storms
#7 Our Old Backup System
#8 Our New Backup System
#9 You Need a System
#10 Jordan Drogue Launch System
#11 Jordan Drogue Retrieval System
#12 Drogue Retrieval, The Devil is in the Details

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2 Comments:

At May 7, 2008 10:43 AM , Blogger www.seriesdrogue.com said...

Hello All,
The secret to retrieving a series drogue is removal of all forward speed.
150 cones @ 1 knot = 18 kg of drag
@ 2 knots= 72 kg
@ 3 knots= 162 kg
@ 4 knots= 288 kg
@ 5 knots= 450 kg
The above figures dont take into account the chain or lead on the bitter end.
I can retrieve my 110 cone series drogue with engine in reverse, and have also retrieved it heaving too.
regards
Bryan Glover

 
At May 7, 2008 3:41 PM , Blogger John & Phyllis said...

Thanks for the load numbers, Bryan, very interesting. However, our loads in our test for our 166 cone drogue seemed to be much more than your 4 knot figure, in the order of 1000kg or more.

I like the idea of retrieving while heaved-to as I say in the post.

I’m less happy about using the engine in reverse to unload the drogue. In my experience, several hundred feet of rope in the water together with a spinning propeller are a bad combination. Add in a big left over sea and a tired crew and I think the chances of getting the drogue or one of its bridles abound the propeller would be unacceptably high.

John

 

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