Tuesday, April 30, 2019

Sea anchor, heaving-to and drogue aboard Rachel Slocum.

- Source:
www.sailinganarchy.com

- The 2018 Golden Globe Race. Started on July 1st in les Sable D'Olonne, France.
Forum: Ocean Racing Anarchy.
The 2018 Golden Globe Race. Pages 33-34 and others.

- I have no experience with Drogue, never had to use one.
If you read through the above caption on S.A, you get an idea of what it is.
- So, I thought to share the experience of one of my clients writing to me about his own sailing and tribulation with the drogue object in question; it is an interesting take.

- The following is from B.P.  Privacy is a concern, except that he is a very well known author. Including about his latest book about the Chappaquiddick incident. " Chappaquiddick Speaks".

- Back to the subject.
- South-Pacific, his integral letter follows.

- " I am sure this letter comes as a surprise, but I've got a lot of time on my hands and thought I'd drop you a line. I'm writing this at 37deg. S. Latitude, 140deg. W longitude about a week out of Pitcairn Island  (if the storm coming along in the next few hours doesn' do me in, and the umpteen ones rolling in behind it).  Two weeks or so far from the Chatams, which are a small group of islands about 450 miles southeast of New Zealand.
The weather has been mostly miserable, with the wind almost constantly out of the north. that seems to be a problem in the Southern Ocean.

- My own note: the letter will read like a novel.  So have the patience for me to copy. (to be continued). Meantime, the news that prompted this segment in the Blog.

Caption: Quote Day 158 Update on Susie Goodall rescue.
_"British woman Susie Goodall remains safe and secure aboard her yacht DHL. Starlight after being pitchpoled and dismasted in the Southern Ocean some 2000 miles West of Cape Horn yesterday...."

-"the good weather doesn't last long, the bad weather seems to last forever. Right now I am running before 40+ knots winds with a double reefed main staysail and have been for the past 36 hours.
This type of sailing gets a bit wearying, with huge seas throwing the boat one way or the other, the cockpit constantly filling up with water, but at least we are headed in the right direction for once. There is a little spot called Maria Theresa reef, spotted by, most likely, a vessel called Mariah Theresa in 1843. No one's seen it since, but because I have a 4,000' fathometer there is a slight chance I can get the exact position. I was able to do that a few times in Indonesia. Before that, there was another one called Sophie Christenson Shoal, spotted (and not seen since) in 1913. I ran right over that one and found no evidence of shoaling at all. The problem is that a lot of these positions are way off because the navigation was not so hot back then. The other problem is that these two shoals lie a couple of degrees north of me, and every mile in that direction has been a difficult claw to windward for the past week.

- My plans after Pitcairn are to head to Mangareva, then the
Marquesas, Tahiti, Cook Islands, Tonga, and Fidji, getting back to New Zealand in November before the cyclone seasons. Or I might head to the Samoa or Tuvalu instead. We will see. Right now I am just taking it one day at the time... First, that damn reef to windward!

- Your boat is performing well, as per usual. A few things on my to-do list when I next get to port, but nothing major. I should be able to cover the entire 3,000 miles of this passage in 26 days, which is not bad, considering the winds have not been favorable for most of the time and I swung to a sea anchor for 31 hours at one point.

- Regarding the sea anchor, this was the first time I attempted to use one, and you might be interested in what happened. The sustained winds were 40 knots, dropping at times to as low as 25 knots, and raising occasionally to 45, with gusts once or twice to 50. The anchor was a "para anchor" 18' diameter, which is the recommended size for this boat. The rod consisted of 200' 3/4" nylon, 200' 3/8" chain in the middle, then another 200' 3/4" nylon, for a total of 500'. This is the recommended arrangement and length of rode (or a large weight, like an anchor, can be substituted for the chain). The drift to leeward was almost exactly 1 knot during the time I was on it.

- Getting the chute deployed (naturally when the wind had already reached 40 knots, at 2 a.m.) was a bitch. The chute started deploying on deck before it could be put in the water. The whole mess was eventually shoved in, with the result that the chute and rode immediately got tangled around the keel! One shroud got sucked into the knot meter impeller, ripping it off. For a few minutes, I was really afraid l'd lose the boat (not to mention myself). With the waves as high as they were, the boat was knocked down repeatedly, tripped by the chute. I somehow got the boat headed downwind (I could not use the motor, as I could see through the underwater porthole with the spotlight on that the line was drifting by it), and very fortuitously, the line untangled and pulled the boat into the wind, but not before getting caught around the fisherman anchor and ripping off the entire mess, brackets and all. Deploying the chute was the most dangerous part of the whole episode. One hopes that with experience (if I ever decide to use the para anchor again) this part of the maneuver will become more successful.

- For the first few hours, the motion was quite comfortable. After 6 hours, the seas had picked up to the point that the motion was
substantially worse than hove-to with sail. Waves swept the vessel from stem to stern, filled the cockpit frequently, worse than being hove-to in the same condition.

- The most uncomfortable times were the lulls when the wind slackened. The boat with less wind force no longer held rock- steady to windward, but paid off. Huge wave threw the boat to starboard or port until the anchor pulled it around again. The motion was awful. The sounds of the strain on the steering gear with wheel lashed down were no pleasant to listen to. I had neglected to raise the windvane, and a gear shattered.

- Finally, there was the real problem of retrieving the anchor, even with the recommended 150' buoyed trip line floating in the water. The buoy on the end of the trip line did not float back with the wind toward the boat as you might expect but generally hung out in the vicinity of the chute itself. After a long time of sea buildup, it was virtually impossible to get to the trip line until the wind had dropped to 25 knots or less, simply because the seas are too high to motor against. Also, until conditions had moderated substantially, the engine had insufficient control to keep the bow to the wind without overriding the rode and fowling the prop. Winching the chute in toward the trip line without using the motor is dangerous to impossible because as the rode shortens, the huge seas jerk the vessel unmercifully.

- This means a decision to use the sea anchor also means one may have to hang to it 1/3 longer than necessary until the seas have moderated sufficiently to bring it in. In my case, that was 10 hours longer than necessary, at the worst time (winds had moderated to the point that the motion was truly annoying). The 30 kn. winds were favorable during those 10 hours, and I can tell you that being rolled around as if I was in a washing machine going nowhere with no hope of reconciling the situation did nothing for my disposition.

- The actual winching in of 500' of line and chain and retrieving the chute took over an hour. Various repairs to the vessel and equipment took several hours more. One shroud of the chute was frayed where it had previously caught on some part of the keel.

- My conclusion after all this is that one should think long and hard before deploying the chute. Maybe if the storm is fast moving you could use it in high gale conditions, but my experience tells me that it would be worthless for a boat my size in much over 60 knots of sustained winds over a long period in open ocean conditions. I think most boats simply could not take it (or would take it, but with disastrous results). I have not yet seen its advantage over being hove-to, and in fact, I see many disadvantages. Maybe a multi-hull has more difficulty heaving-to, and for this type of vessel, it could be a help. It seems that most of the praise for a sea anchor comes from multi-hulls, or owners of power boats ( which of course have no other way of heaving-to). Maybe some of the monos who do rely on the chute have never tried to hove-to, or the boats are too light or have to short a keel to manage it.

- The bottom line is that a parachute sea anchor seems to be little more than a device for assisting a vessel to heave-to, in moderate gale-force winds. It does not seem to possess any magical properties that give a vessel a better chance to survive high winds and seas than more traditional methods of heaving-to, or running with a drogue unless these traditional methods are not practical due to boat design. To give a good idea of what it's like, anchored at sea with a para anchor is no different in the slightest from being anchored to seabed in an open roadstead in comparable winds, with a long rode out.

- A few days ago I experienced nearly identical conditions. In this case, we hove-to under double reefed staysail, jogging slightly into the wind at 3-4 knots. Winds were 40 kn., peaking at 47. The motion was far easier than with the chute. Much less water made it into the cockpit. There was no damage to the vessel.

- After nine hours winds had moderated to 30 kn. Being favorable, we were underway within minutes with no fuss just by heading downwind and setting the wind vane. Winds have gradually increased to the 40+ knots we have now, but I have no plans to return to the sea anchor.

- This a long-winded account, but I was trying to organize my thoughts about this as I am writing to you. It would be interesting to hear your thoughts on the matter. I am sure you have had some feedback on this before, or have your own ideas about it.

- Best regards, Bill

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