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Sea Anchors on Rowing Boats

S/R-1 Aluminum Dory

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STOMATOS/R-1

Aluminum Dory

28' x 2.5 Tons, Dagger Boards

12-Ft. Dia. Sea Anchor

Force 5 Conditions

File S/R-1, obtained from Ned Gillette and Mark Eichenberger - Vessel name Sea Tomato, aluminum rowing dory designed & built by Ned Gillette, LOA 28' x LWL 24' x Beam 7' x Draft 18" x 2.5 Tons - Dagger boards - Sea anchor: 12-ft. diameter Para-Tech on 300' x 1/2" nylon three strand rode with 1/2" stainless steel swivel - Full trip line - Deployed during passage of frontal troughs in deep water in the Drake Passage and off the coast of Antarctica with blizzard & winds of 25 knots - Drift was estimated to be 10 n.m. during 21 hours at sea anchor.

Victor Shane's company sponsored the team of Ned Gillette and Mark Eichenberger in their successful attempt to row a specially designed dory, Sea Tomato, from Cape Horn to the Antarctic, a distance of 1000 miles across the treacherous Drake Passage. They supplied the expedition with a small speed-limiting drogue, a Jordan series drogue (88 cones on 300 ft. of line), a 12-ft. diameter Para-Tech (main sea anchor) and a 9-ft. diameter BUORD (backup sea anchor).

Taken in the waters off Punta Arenas, Chile. Mark Eichenberger test-deploying the Jordan series drogue supplied by Victor Shane of Ned Gillete's Antarctic row - see File S/R-1 (Ned Gillete photo)
Taken in the waters off Punta Arenas, Chile. Mark Eichenberger test-deploying the Jordan series drogue supplied by Victor Shane of Ned Gillete's Antarctic row - see File S/R-1 (Ned Gillete photo)

Shane saw in this expedition an opportunity to put several drag devices to the test. As it turned out, however, the crew never did get into a storm, other than the one that blasted them off in the beginning, which was driving them exactly where they wanted to go.

They did derive benefit from the 12-ft. diameter Para-Tech sea anchor in terms of drift control, however. When Mark Eichenberger afterwards visited Shane in Santa Barbara he said that no sooner had they sighted the coast of Antarctica than the weather turned sour and a Force-5 blizzard started pushing them back out to sea. They then deployed the sea anchor, which kept them more or less in place for 21 hours. He said icebergs, driven along by the wind, were drifting by the boat during that period.

Ned Gillette is both mountaineer and sailor, having conquered Everest and now Cape Horn. Author of the book Everest Grand Circle, he is also a free-lancer for the National Geographic Society. His article, Rowing Antarctica's Most Mad Seas, appeared in the January 1989 issue of National Geographic Magazine. Mark Eichenberger was a long time sailor and adventurer. The following is a transcript of the feedback obtained from Mark:

The sea anchors were key to our strategy on our expedition to row from Cape Horn to Antarctica, and the 12' diameter `FORCE 10' worked remarkably well. It was easy to deploy and retrieve, and it was effective in practically eliminating our wind drift. The only reason we did not use them more than we did is that we were blessed with very fortunate weather, the winds being mostly favorable and moderate.

During the third day out, 24 Feb. 1988, the winds from the gale which had blasted us off from the coast diminished gradually until in the evening they were W to WNW about Force 5. We had begun rowing at 0900 that morning and continued throughout the day until midnight whereupon it became too dark to row effectively. So we put out the sea anchor and lay to it until 0940 the following morning, about 10 hours during which our average drift was 0.9 knots. We most likely would have had a current of .5 knot or more in this part of the Drake Passage. On the seventh day, around midnight, a frontal system passed over us and the wind shifted from WNW eventually to settle on SW with overcast and rain. The conditions were not rough; however, the wind was contrary to our purpose and, in order to hold the southing and westing that we had gained, we once again deployed the sea anchor. From 0230 until mid-afternoon we lay to the sea anchor, nearly 13 hours. Our average drift had been 0.6 knots. Interestingly, in the morning we had a pair of Southern Bottlenose Whales, about 30 feet long, come by to investigate this enormous orange jelly fish - the sea anchor. They swam between us and the sea anchor, but fortunately decided it was inedible and left.

The third and final use of the sea anchor came on our approach to the Antarctic coast on the 13th day out. A light westerly wind gave way to a fresh breeze (Force 5) out of the southeast, so at 1930 hrs. we deployed the sea anchor to hold what ground we had gained, and lay to it from late on the 4th of March, throughout the night and following day until 1630, a total of 21 hours. We kept an "anchor watch" throughout the period as there were icebergs scattered around and occasionally growlers and bergy bits would drift down past us.

EPILOGUE: In December 1991 Mark Eichenberger was working on the ice breaker Erebus in the Strait of Magellan when a devastating storm blew into Punta Arenas. Two great waves washed over Erebus' decks in rapid succession. Mark was swept overboard and lost at sea. He was a good friend of Shane's and an accomplished seaman. We are all diminished by the passing of a comrade. We bid defiance to the sea, in honor of his memory.

Sea Anchors on Monohulls

S/M-13 Bristol Channel Cutter

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BCHANNELS/M-13

Bristol Channel Cutter

26' x 7 Tons, Full Keel

9-Ft. Dia. BUORD Sea Anchor

Force 8 Conditions

 

File S/M-13, obtained from Gary Kaye, Sidney B.C. - Vessel name Mintaka II, hailing port Vancouver B.C., designed by Lyle Hess, LOA 37' (with long bowsprit) x LWL 26' x Beam 10' x Draft 5' x 7 Tons - Full keel - Sea anchor: 9-ft. diameter BUORD on 300' x 5/8" nylon three strand rode with 1/2" galvanized swivel - No trip line - Deployed in a whole gale in deep water approx. 140 miles west of Coos Bay (Oregon coast) with wind sustained at 40 knots and seas of 20 ft. - Use of the "Pardey Bridle" arrangement held the bow 50° off the wind. Drift was estimated to be about 50 n.m. during 52 hours at sea anchor.

In August 1987 Mintaka, a Lyle Hess designed Bristol Channel Cutter, was headed for San Francisco from Victoria B.C., when she ran into a whole gale at about latitude 44° N, longitude 127° W, (some 140 nautical miles west of the Oregon Coast). Gary and Sandi Kaye deployed a 9-ft. diameter BUORD parachute, using the Pardey bridling method (see files S/M-3, 4). All told, this traditionally designed, heavily built cruising yacht was hove-to for 52 hours, the wind sustained at 40 knots and seas of 20 feet.

Since there were no written notes, opinions or observations accompanying the DDDB form that Victor Shane received from these intrepid sailors, it was likely a matter of routine seamanship. Victoria, has a rich seafaring history. It is the hailing port of Taleisin, as well as a number of other boats in this database. It is inspiring to find boats like Mintaka following in the Voss/Pardey tradition of safe voyaging under mast and canvas. When one of these boats get into heavy weather the crew members are not wanting for a tactic. They heave-to, ride out the storm, and quietly resume their cruising.

Sea Anchors on Monohulls

S/M-12 Carter 33 Sloop

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CARTERS/M-12

Carter 33 Sloop

32' 7" x 4.5 Tons, Fin Keel

12-Ft. Dia. Sea Anchor

Force 8-9 Conditions

 

File S/M-12, obtained from Steven Callahan, Ellsworth, Maine - Vessel name Karpouzi, hailing port Lamoine, sloop, designed by Dick Carter, LOA 32' 7" x LWL 25' x Beam 11' x Draft 5' 6" x 4.5 Tons - Fin keel - Sea anchor: 12-ft. diameter Para-Tech on 250' x 5/8" nylon three strand with 1/2" galvanized swivel - No trip line - Deployed during a gale in deep water north of Bermuda, with winds of 35-45 knots and seas of 8-12 ft. - Vessel's bow yawed 30° off to each side with two opposing sets of waves approaching from dead ahead and dead astern - Drift was estimated to be 3.25 miles during 4 hours at sea anchor.

Steven Callahan is well-known for his best seller, Adrift. The book is a journal of the seventy-six days that he spent drifting in a life raft after his 21-ft. sloop Napoleon Solo hit an unidentified object and sank in the middle of the Atlantic on 4 February 1981. He journeyed to the limits of human despair in those seventy-six days, yet in the end cheated death and emerged a survivor. Adrift (1986, Houghton Mifflin Co.) won the Salon du Libre Maritime award and has been translated into twelve languages.

Callahan has been involved in many areas of the marine industry since 1968. He has logged tens of thousands of blue water miles, including one single-handed and three double-handed Atlantic crossings. A former contributing editor to SAIL and to SAILOR, he wa at the time of this writing associate editor of Cruising World.

Victor Shane delivered a 12-ft. diameter Para-Tech sea anchor to Callahan in 1989, for use and evaluation on board his boat Karpouzi, a fin-keeled Carter 33 sloop. The para-anchor was used a year later, in a Force 8 gale north of Bermuda. Here is a transcript of Callahan's feedback

On 28 May, 1990, Karpouzi and her three merry crew were completing a delightful week of sailing from St. Martin, and approaching Bermuda. We planned to bypass the island and continue directly to Maine. Our weather, however, was deteriorating, and the forecast was for a day or so of rain and winds of 20 knots.

By midnight the barometer began to fall more rapidly - about .05 inches per hour, and we were broad reaching fast under double-reefed main and working jib. We could hear Bermuda Harbor Radio, about 30 miles east of us. Harbor radio was busy with incoming traffic problems and reports of a developing low that no one had paid much attention to. Through the night they logged winds to 42 knots and predicted seas to 25 feet.

As we proceeded north, the wind strengthened and backed slightly so that we ran dead before waves that I estimate to have been 10-15 feet. All was under control. The barometer began to rise by 06:00 on 29 May and the wind lightened slightly for about a half hour, but then the wind came up hard again and continued to back. In a very short time we were hit with heavy head winds and significantly rising seas from dead ahead, while we continued to surf down 10 foot waves from dead astern.

In 50,000 miles of offshore sailing I have often dealt with heavy seas from a variety of directions, but that was the first time that significant waves approached each other from precisely opposite direction. This, of course, set up a dreadful sea state. When crests coincided, the peaks jumped skyward and the wave slopes were very steep. (Note, in the attached DDDB form, wave height, period, and length are very approximate values because they were all extremely variable due to 180° wave collisions - a bit like being in a blender). I estimated wave height by standing on the cabin top - my eye level about 10 feet above water.

Karpouzi's beam is 11 feet, or the average size of the breaking waves, so I declined Neptune's invitation to get rolled by laying broadside to the waves. We could not carry much sail in the wind, and in any case, heaving-to or beating would put the boat too far off of the approaching waves, increasing the danger of being stalled, pushed back, and rolled. The only feasible solution was to put out the sea anchor. We decided to set the sea anchor just as we would a regular anchor.... We keep the anchor in its own locker in the head of the V-berth, with the rode flaked under it. This allows us to run the rode straight aft, out of the cabin, and forward over the anchor roller.... As I dunked the anchor over, we threw the engine in neutral and drifted back. The parachute opened perfectly and within thirty feet it began pulling, allowing us to pay out line and adjust things just right. A few waves towered above me and one slammed over the foredeck just irritatingly above boot level.

We payed out about 250 feet of the rode and adjusted the length every 30 minutes to avoid chafe. This length proved enough; the sea anchor sometimes neared the surface so we could see it and it rode about a wave trough away from us. I chose not to use a tripping line to avoid any possible foul up, but we tied a huge Norfloat ball to the float line, which we could easily see from far away.

The boat did sway from side to side, creating huge side loads on the anchor roller cheeks, so be advised to use either very sturdy chocks or heavy roller. Ours was a heavy duty universal roller that is advertised for boats to 54 feet, but I believe the side loads on a 54 foot boat would have bent the roller in half. As it was, I was a bit worried. To control sway and remove these side loads, next time I will likely set the sea anchor from a regular chock and possibly haul it off to the side with a rolling hitch and secondary rode to lay 20 to 30 degrees from nose onto the waves. Note that the rode jumps up as the bow plunges downward, so whatever chock you use should have a positive lock across the top.

The only real problem we encountered was a very heavy loading on the steering gear. Karpouzi is tiller steered and at first we just tied it off, but as large waves broke on her, she surged aft, stretching the anchor rode until stopped and pulled forward again. The rudder was yanked mightily by the backward motion and the tiller wiggled about like a snake. Our solution was to give the tiller a shock absorber, just as the nylon anchor rode acted as a shock absorber for Karpouzi. We tied half inch shock chord to the tiller, which allowed it to move 20 or 30 degrees without much problem but prevented the rudder from going hard over, where it could shear off its fittings.

After only four hours on the sea anchor, the wind continued to back and lightened, so that finally we were laying broadside to the now calming waves. It was quite uncomfortable and more dangerous than setting sail. With full throttle we were able to easily retrieve the rode as we steamed up to the pickup float, which we noted had enough windage to float to leeward of the anchor most of the time, so we had no worry about tangling the sea anchor lines. It was a simple matter to pick up the float, trip line, and anchor. Within 20 minutes all was stowed away and we were off.

We drifted 3.25 miles in those four hours, which is a bit more than I expected, but currents around Bermuda are very uncertain. Further tests will compare Karpouzi's normal drift rate with her drift with the sea anchor set. I will certainly be more eager to set the sea anchor in marginal conditions in the future.

It is disappointing to note that Karpouzi's bow was yawing 30° off to each side (i.e., through a total arc of 60°). By all tokens the sea anchor was big enough to have done a better job.

Victor Shane suspects that the conflicting waves - approaching from ahead and astern - might have had something to do with this. Certainly the angle of yaw will have a great deal to do with the amount of slack that finds its way into the system as well. Much of this slack can be a result of orbital rotation causing convergence between boat and sea anchor. Essentially the wind pushes the boat away from the sea anchor, keeping the system taut. Orbital convergence, however, can move the boat and sea anchor toward one another, introducing slack into the rode, sometimes by an amount equal to twice the wave height (twenty feet of slack rode in ten foot seas, for example). Callahan reports significant waves approaching each other "from ahead and astern." Here, not only do we have the rotation associated with the waves approaching from ahead, but also, possibly, the rotation associated with waves approaching from astern, as evidenced by the heavy loads on the rudder, mentioned. This combination could have the effect quadrupling the amount of slack - and attendant yaw - when the crests of the secondary waves coincide with the troughs of the approaching waves.

 

Sea Anchors on Monohulls

S/M-11 Venture 222 Sloop

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VENTURES/M-11

Venture 222 Sloop

22' x 1 Ton, Centerboard Keel

12-Ft. Dia. Sea Anchor

Force 3-4 Conditions

File S/M-11, obtained from Harley L. Sachs, Houghton MI. - Vessel name Gamesmanship, hailing port Houghton, Venture 222 sloop, designed by Roger MacGregor, LOA 22' x LWL 18' 6" x Beam 7' 4" x Draft 4' 6" x 1 Ton - Centerboard swing-keel - Sea anchor: 12-ft. Diameter Para-Tech on 100' x 3/8" dia. nylon three strand rode, with 5/16" stainless steel swivel - No trip line - Deployed during passage of frontal trough in shallow water (7 fathoms) on Lake Superior with wind gusting to 20 knots - Vessel's bow yawed 10° with the swing-keel down and 45° with the swing-keel fully raised.

Way back in June 1988 Victor Shane sent a letter to the editor of Cruising World Magazine, asking for feedback on sea anchors and drogues. Mr. Harley Sachs read the letter and responded with the following feedback:

For your database: Vessel, MacGregor Venture 222 sailboat, swing keel, transom hung spade rudder, LOA 22 feet, weight about 2,000 lbs. Conventional wisdom (Chapman and the boating supply catalogs) suggested a 30-inch conical drogue sea anchor. This does not work with my boat.

My wife and I decided to test this equipment on a breezy day with four-five foot waves on Lake Superior. I launched the 30-inch cone from the bow on about fifty feet of line and lowered all sail. The boat assumed a position with the seas abeam and would not face into the waves no matter what the rudder position was. With the sea anchor shifted to the stern, the result was the same. The motion of the boat was violent and I could hardly move about on deck.

I hoisted a small riding sail on the back stay. This had an immediate, remarkable damping effect on the boat's motion but did not cure the beam-on attitude of the boat to the seas. The 30-inch conical drogue was pronounced a failure.

Sachs turned out to be a multi-faceted sailor who was, among other things, writing a book on nautical humor (Irma Quarterdeck Reports, Wescott Cove Publishing, 1990). Shane mentioned the similarity between his disappointing experience with the small cone and those documented by Adlard Coles in Heavy Weather Sailing, and then asked if Sachs would consent to trying out a 12-ft. diameter parachute sea anchor. This was to be a "controlled experiment" - same boat, same conditions, but a much larger sea anchor. He agreed, and Shane sent him the sea anchor. Three months later he tried it out in similar conditions and sent back the following report:

Subject: Test of 12-ft. diameter para-anchor. With westerly winds gusting to 20 mph after the passage of a cold front, we motored offshore to a point outside the Lower Entry harbor on Keweenaw Bay of Lake Superior. With the engine shut off we drifted about 1 knot downwind with the wind and waves off the stern quarter, the same attitude I experienced when unsuccessfully testing my 30-inch conical drogue.

About a mile offshore, in about forty feet of water, I set up the 3/8" laid nylon rode to launch the para-anchor.... As instructed, I launched the float first, which functions as a pilot chute, drawing the para-anchor away from the boat as the boat drifts downwind. This could hardly be easier, for the chute slid overboard and in two or three minutes filled beautifully. Once it filled, it stuck in the water almost like a post and the Venture 222 bow came right up into the wind exactly.

With the keel down the Venture did not yaw more than 10°. With the keel retracted, there was 30°-45° of yaw, as the Venture bottom has almost no lateral resistance with the keel retracted. Rudder was tied amid-ships.CB
When retrieving the sea anchor, one cannot pull the anchor to the boat. One pulls the boat to the anchor, and that takes strength. I'm glad it wasn't a three ton vessel! Once I could reach the parachute strings, it was dead easy to spill the water out and haul it aboard. Took no effort at all, pulling one string. Once spilled, the para-anchor is a limp sack.

We did drift slightly with the anchor. In six minutes the bearing on the lighthouse half a mile away had shifted by ten degrees.... In spite of the holding power, the para-anchor is in a fluid, and the force exerted against it will cause it to slip through the water.

Apart from showing the improvement that can be expected with the use of sea anchor that is large enough, this file reveals something important about centerboards and swing keels as well.

It was previously thought that sailboats would yaw less at sea anchor with their centerboards and keels raised. Not so. At least not on this boat. Apart from tripping on the rudder as the boat surges backward, the CLR moves aft as well. With the CE now so far forward the bow will tend to yaw excessively. When the swing keel is again lowered, however, the CLR moves closer to the CE and the wind doesn't have the same lever. Notwithstanding, boards - and swing keels - should NOT be lowered all the way down in storms.

CAUTION: Lowering board/s and keels, or lowering them all the way, may give the yacht something to trip over in life-threatening storms. By and large, and as an important rule of seamanship, boards and keels should be raised in heavy weather. Or at least raised enough so that the yacht can "slip-slide," and not have a large appendage to hang up on and trip over.

Sea Anchors on Monohulls

S/M-10 Hinckley Bermuda 40 Yawl

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HINCKLEYS/M-10

Hinckley Bermuda 40 Yawl

40' x 10 Tons, Full Keel & Centerboard

12-Ft. Dia. Sea Anchor

Force 8 Conditions

 

File S/M-10, obtained from the owner of the boat - Vessel name Windswept, hailing port Gloucester MA., Hinckley Bermuda yawl, designed by Bill Tripp, LOA 40' x LWL 28' 10" x Beam 11' 9" x 10 Tons - Full keel with centerboard drawing 8' when down and 5' with the board raised at sea anchor - Sea anchor: 12-ft. Diameter Para-Tech on 400' x 1/2" nylon three strand rode with 5/8" galvanized swivel - No trip line - Deployed during passage of frontal trough in shallow water (30 fathoms) off the coast of Maine, with winds of 35-40 knots and seas of 8-10 feet - Vessel's bow yawed less than 10° - Drift was estimated to be 2 n.m. during four hours at sea anchor.

The 12-ft. diameter Para-Tech sea anchor was deployed in a low system, about thirty miles offshore, near Portland, Maine. Transcript:

This was not a whole gale or survival storm. I was alone, wanted to rest, wanted to minimize drift, and wanted to experiment with my sea anchor. After deployment my yawl lay absolutely bow to the wind and waves with very little yawing. My boat does not have a cutaway forefoot, the board was up and the waves were not high enough to blanket the wind when the boat was down in the troughs.

With 400 ft. of rode there was absolutely no shock loading at all. No feeling of either being pulled through the waves or falling backwards on the rudder. My boat rode like a duck up and over each wave always nose to the wind. Altogether a very pleasant, safe and secure feeling.

The only two things I worried about were (a) commercial fishing interests in the area not seeing me and running over my anchor line, (b) cross waves approaching from the side of the boat and rolling her. With no sail set there is nothing to steady the boat side to side.

The Hinckley Bermuda 40 has a symmetrical full keel with considerable overhang at both ends (the waterline length of the boat being only 28' 11"). This particular Hinckley also has an auxiliary centerboard, which was in this case raised at sea anchor. Even so, she behaved well and pointed very high into the seas, doubtless because of the aft windage of her rig. Look for the relative positions of the CLR and CE and you will see a recurring pattern in all the monohull files.

Sea Anchors on Monohulls

S/M-9 Hunter 40 Sloop

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HUNTERS/M-9

Hunter 40 Sloop

40' x 9 Tons, Fin Keel

9-Ft. Dia. BUORD Sea Anchor

Force 9 Conditions

 

File S/M-9, obtained from Captain Jerry Sidock, Fort Myers Beach, FL. - Vessel name Bounty Hunter, hailing port Fort Myers Beach, Hunter sloop, designed by Warren Luhrs, LOA 40' x LWL 32' 6" x Beam 13' 6" x Draft 5' x 9 Tons - Fin keel - Sea anchor: 9-ft. Diameter BUORD on 300' x 5/8" nylon three strand rode with 1/2" stainless steel swivel - Full trip line - Deployed in a gale in shallow water about 100 miles off the coast of Venezuela, with winds of 40-50 knots and seas of 15 feet - Vessel's bow yawed 20°-30° off to each side - Drift was 11 n.m. (confirmed by Loran & Satnav) during 14 hours at sea anchor.

Bounty Hunter, a fin-keeled Hunter 40, was on her way to Rio from Florida when she ran into a gale some 100 miles off the coast of Venezuela. The owner of the boat, Captain Jerry Sidock, being single-handed and tired at the time, deployed a 9-ft. BUORD off the bow. In one of several telephone conversations with Victor Shane, Captain Sidock reported that the bow held into the seas in a satisfactory way, yawing as she would at ground anchor, 20-30° off to each side, but certainly no more than 30°.

Note the same parachute sea anchor being used by different boats with varying results. Compare Bounty Hunter's underwater profile with those of the Pilot Cutter and the Vancouver 27 in the preceding files. Bounty Hunter has a more symmetrical underwater profile, her center of lateral resistance being a little closer to the center of effort of her rig. Additionally she was in stronger winds as well. Note however that her bow did yaw up to 30° off to each side, indicating that the yacht could do with a larger sea anchor

Captain Sidock knows the Caribbean Islands well. In his voyages to the Caymans, Jamaica, Roatan, Belize, Honduras, Guatemala and South America he often uses the BUORD off the stern for rest periods. There is then hardly any side-to-side yaw at all.

Note that there is nothing wrong with using a sea anchor off the stern for rest and recuperation, drift control and damage control in moderate conditions. Moreover, for non heavy weather use the rode need not be very long either. Deploy the parachute, pay out a hundred feet of line and cleat it off. Now you can rig the awning over the boom, prepare a meal in peace and relax for a while, the whole ocean your own private anchorage. From Captain Sidock's handwritten feedback:

I would like to say that I don't think that common sense would permit me to leave shore without my sea anchor. It is just too difficult at times to continue on when short-handed, or rather single-handed, as I am most of the time. It is at that time that I look for assistance from other sources, such as a sea anchor.

Sea Anchors on Monohulls

S/M-8 Vancouver 27 Cutter

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VANCOUVRS/M-8

Vancouver 27 Cutter

27' x 5 Tons, Full Keel & Cutaway Forefoot

9-Ft. Dia. BUORD Parachute

Force 7 Conditions

 

File S/M-8, obtained from Anthony Gibb, Victoria, B.C. - Vessel name Hejira, hailing port Victoria, Vancouver cutter, designed by Robert Harris, LOA 27' x LWL 22' x Beam 8' 6" x Draft 4' x 5 Tons - Full keel & cutaway forefoot - Sea anchor: 9-ft. diameter BUORD on 275' x 1/2" nylon three strand rode with 1/2" galvanized swivel - No trip line - Deployed during passage of frontal trough In deep water in the Tasman Sea with winds of 35 knots and confused seas of 12 feet - Vessel's bow yawed as much as 90° off to each side.

Hejira, a Harris-designed Vancouver 27 on a world cruise, crossed from Nelson, New Zealand, to Sydney, Australia in 15 days, a distance of 1,265 miles.

As with most other crossings of the Tasman this one was not a pleasant one. The crew was harassed by a confusion of waves and swells from both southwest and northeast, which harassment did not end until the last two days of the crossing.

During a period of 30-35 knot south-westerly winds and 12-foot seas the crew deployed a 9-ft. diameter BUORD. As in the previous file, the parachute did not do a satisfactory job. Transcript:

The BUORD never set straight forward off the bow. It remained directly off the beam. It gave one the feeling of lying a-hull. It was only when a particularly large wave approached and took up the slack in the rope that the BUORD brought the bow through the wave....

The only other time that the BUORD brought the bow into the waves was when, after 4 hours, I decided to pull it in. When the line was pulled in so that there was only 50 feet out, then it seemed that the bow wanted to stay pointed upwind. I did not leave it there long enough to test it, so I don't know what the BUORD would do in the long run....

Again it might be asked why the same parachute that pulled the bow of a fin-keeled J-30 into the seas (File S/M-6) would not do the same thing for a Vancouver 27. And again, the answer has to do with the amount of wind, the keel configuration, the rig, and the relative positions of the CLR and CE on the different boats. The J-30 has a small, centrally located fin keel. The Vancouver 27 has a full keel with a cutaway forefoot. The J-30 had sustained winds of 60 knots. The Vancouver had winds of 35 knots.

A larger parachute sea anchor might have made a difference as well. We would like to emphasize that the canopies of these BUORDs are made of coarsely woven mesh material, "the sort of thing you would use to strain plankton out of the sea with" as one sailor described it. Although they have a nominal diameter of about 9 feet, they do not have the holding power of a 9-ft. diameter, zero-porosity sea anchor. Remember, they are designed for dropping torpedoes into the sea and need to have a great deal of "give" built into their canopies.

By coincidence, the Pardeys ran into Anthony Gibb in Australia, and had this to say to Victor Shane in another letter: "Later discussions make us wonder if he had enough wind, or possibly her laying so far off the wind might have been caused by her high bow, the tanks stowed on her foredeck and a very high deck house, combined with a cutaway forefoot."

Sea Anchors on Monohulls

S/M-7 Pilot Cutter

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PILOTCTRS/M-7

Pilot Cutter

32' x 5 Tons, Full Keel & Cutaway Forefoot

9-Ft. Dia. BUORD Parachute

Force 8 Conditions

 

File S/M-7, obtained from Dennis Lueck, Pensacola FL. - Vessel name Wind Song, hailing port Pensacola, Pilot Cutter designed by Frank Parrish, LOA 32' x LWL 20' x Beam 9' x Draft 5' x 5 Tons - Full keel & cutaway forefoot - Sea anchor: 9-ft. Diameter BUORD on 300' x 1/2" nylon three strand rode with 1/2" galvanized swivel - No trip line - Deployed during passage of frontal trough in shallow water (6 fathoms) off the Florida coast with winds of 35-40 knots and choppy seas of 8 feet - Vessel's bow yawed as much as 90° off to each side in the gusts.

Wind Song, a brand new Pilot Cutter, was being sailed from Tampa to her home port of Pensacola when a weather front arrived. The crew decided to play it safe with the new boat and deployed a 9-ft. BUORD, in 6 fathoms of water, about 30 miles offshore and due west of Bayport, Florida. The parachute did not do a satisfactory job of pulling the bow of Wind Song into the seas. The boat would get beam-on to the seas in the gusts. Notwithstanding, the motion was still much better than lying a-hull. Here is a transcript of her owner's feedback:

After rounding up to deploy the sea anchor, we forgot to return the rudder amidships, so it was hard to port all night (and not discovered till morning). As a result (I believe) the boat would get beam-on to the seas in the gusts and then roll. As it was, the motion was still much better than lying a-hull....

The rode did hit the bobstay and whisker stays quite often but did not chafe. We tried the "Pardey Bridle," but the snatch block stayed against the hull and we were afraid of chafe....

Incidentally, the boat was brand new and we were bringing it home. It had been dead calm and we were motoring north about 50 miles north of St. Petersburg when the front came through. As we had no sailing experience with this boat and it was night, we elected to heave-to with the sea anchor. Today, with similar conditions, we would sail the boat reefed down.

Why didn't the sea anchor pull the bow of this yacht into the seas? The problem of side-to-side yaw is related to the shape of the hull and keel, the position of the CLR (center of lateral resistance), the type of rig and the position of the CE (center of effort). It is most aggravated when the CLR is well aft and the CE well forward. This gives the wind a larger lever to push the bow off.

Boat design has always been the art of compromise and naval architects have seen the cutaway forefoot as something that enhances the course-keeping qualities of a yacht and lessens her tendency to broach in strong following seas. As long as such a yacht is sailing forward her underwater profile resembles an arrow in flight. The trade off, of course, is her behavior at anchor.

More than likely, however, Wind Song just didn't have enough wind. Seraffyn has unevenness associated with her underwater shape as well, but recall the Pardeys' words in File S/M-3, "If there was a lot of wind, the para-anchor held her pretty close to head to wind."

Sea Anchors on Monohulls

S/M-6 J-30 Sloop

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J30S/M-6

J-30 Sloop

30' x 3.75 Tons, Fin Keel Sloop

9-Ft. Dia. BUORD Parachute

Force 11 Conditions

File S/M-6, obtained from Paul C. Brindley, Houston TX. - Vessel name Heaven & Hell, hailing port Houston, J-30 sloop, designed by Rod Johnstone, LOA 30' x LWL 25' x Beam 11' 6" x Draft 6' 6" x 3.75 Tons - Fin keel - Sea anchor: 9-ft. diameter BUORD on 300' x 3/4" nylon three strand rode with no swivel used - No trip line - Deployed during a storm in deep water in the Gulf of Mexico, about 120 miles Southeast of Galveston, with winds of 60 knots and combined seas of about 30' - Vessel's bow yawed about 10° - Drift was .5 -.7 knots during 4 hours at sea anchor.

This is the first file that Victor Shane documented after starting Para-Anchors International in 1981.He comments that it tends to stick in the mind, like that first high school date. It is an important file in other respects as well. The boat, a fin-keeled J-30, rode very well to the 9-ft. BUORD parachute. Up to that time conventional wisdom had it that sea anchors were useless on board so-called "modern fin-keeled sailboats." This was a turning point of sorts.

In a letter to Victor, dated 2 November 1986, Donald J. Jordan, author of widely publicized articles on capsize prevention and inventor of the series drogue wrote the following (reproduced by permission): "Dr. Brindley called and gave me a comprehensive description of his experience.... As you say, the J-30 rode very well in that type of wind and sea. This is the first well-documented instance of a modern sloop riding properly with a sea anchor from the bow."

The 9-ft. diameter BUORD pulled the bow of this yacht into 60-knot winds and 30-ft. seas in a satisfactory way. It kept it there for four hours. However, the crew had inadvertently omitted to use a swivel on the parachute terminal, and the canopy's rotation resulted in a fouled-up useless mess of parachute and kinked-up rode.

After retrieving the mess and stowing it the best they could the crew then used the boat's inboard engine to jog into the seas. Apart from a few near knock-downs, Heaven & Hell emerged from the ordeal intact. From Dr. Brindley's handwritten feedback:

The drogue [meaning sea anchor] worked well. We could have eaten soup below until it twisted shut as we had inadvertently left off the swivel. We made about .5-.7 knots sternway, checked by the Loran. It went to 4-5 knots when the chute twisted shut. I much preferred the bow into the waves.

 

Sea Anchors on Monohulls

S/M-5 Steel Schooner

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GOODJUMPS/M-5

Steel Schooner

75' x 36 Tons, Full Keel

28-Ft. Dia. Parachute Sea Anchor

Force 10-11 Conditions

 

File S/M-5, obtained from Jeremiah Nixon, St. Louis MO. - Vessel name Goodjump II, hailing port St. Louis, steel Schooner, designed by George Sutton, LOA 75' x LWL 62' x Beam 15' x Draft 6' 2" x 36 Tons - Full keel - Sea anchor: 28-ft. diameter C-9 military class parachute on 600' x 1-inch nylon three strand rode, with 5/8" galvanized swivel - No trip line - Deployed in deep water during a storm near 39° 50' N, 49° 30' W (mid-Atlantic) with winds of 60 knots and seas of 18' - Vessel's bow yawed 10° - Drift was about 18 n.m. during 18 hours at sea anchor

Goodjump II was sailing to Portugal from the U.S. east coast. The skipper, Jeremiah Nixon, had purchased a para-anchor from the author's company. It was a 28-ft. diameter C-9 military parachute, converted into a sea anchor. This parachute has been a staple of the Armed Forces for decades, and is still in use by the Air Force. You can tell a C-9 by the colors of the canopy, either red and white, or a combination of red, white, gold and olive drab. C-9s have 28 suspension lines.

Shane Victor has handled hundreds of C-9's to date, each and every time with awe and amazement. Little wonder World War II pilots used to refer to their parachutes as "silken angels." Light in weight, resilient and strong, a military parachute (not to be confused with lighter sport parachutes) embodies eighty years of development and refinement. Government contracts require that C-9 parachutes be able to negotiate dynamic loads of 5,000 lbs. without failure - they have to be test-dropped from aircraft flying at high speeds with dummies attached.

When Goodjump II ran into a storm in the middle of the Atlantic, the crew decided to put out the chute. They had some initial difficulty in getting the big canopy in the water. The wind took hold of it on deck and it was almost airborne . The crew persevered, however, and finally had the chute properly deployed on 600 feet of nylon rode. Goodjump II rounded up into the seas, her bow nicely snubbed to her parachute sea anchor in 18-ft. seas. Transcript:

The para-anchor worked perfectly, we rode nicely. Learned the hard way to deploy it from the windward side of the boat by pushing it right into the water while holding it against the side of the boat. It got loose on our first effort on the lee side and went into the air.

You asked the question of the angle and movement of our bow during the storm. I cleated the rode to the forward port cleat and as a result the bow held about 10° to the right of the wind and there was no swing from side to side that I noticed. In fact the deck was dry and there was no spray or pounding. The 600 feet of rode stretched and raised out of the water at the point of wave crest and then came back down with an easy controlled feeling.

We drank beer and ate chili during the worst and I got a solid 6 hours of sleep at a time when we had to wear a safety harness because of wind when we went forward to check on chafe.

No trip line is necessary. Just motor up to it and bring it up. These are some of the reasons why I consider this equipment the most important safety item on my boat.... I will never make an ocean passage without one on board. People must realize that ocean cruising can be safe if you go with the idea that you will go into a defensive position before the seas build too high. The flat-out philosophy of professional racers must be disregarded by the small crew cruising yachts

(Note: The problem of the wind inflating parachutes prematurely on deck can be minimized by wetting down the parachute beforehand. Nylon cloth is much more manageable and less likely to fly open in the wind when wet and heavy. The other alternative is to use a deployment bag.)