Category Archives: Sea Anchors on Trimarans

Trimarans deploying a sea anchor off the bows

Sea Anchors on Trimarans

S/T-1 Trimaran, Horstman Tristar Ketch

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HORSTMANS/T-1

Trimaran, Horstman Tristar Ketch

39' x 22' x 8 Tons

28-Ft. Dia. Parachute Sea Anchor

Force 12 Conditions

 

 

File S/T-1, obtained from Joan Casanova, Oregon City, OR. - Vessel name Tortuga Too, hailing port Seattle, Trimaran, Tristar ketch, designed by Ed Horstman, LOA 39' x Beam 22' x Draft 44" x 8 Tons - Sea anchor: 28-ft. Diameter C-9 military class parachute on 400' x 3/4" nylon three strand tether and bridle arms of 60' each, with 1/2" galvanized swivel - Full trip line - Deployed in numerous storms during 18-year cruise from Seattle to African coast, the Southern Ocean and back to Texas - Severest use case was over the Burwood Bank, between Cape Horn and Falkland Islands, with winds of 85-100 knots and seas in excess of 30' - Vessel's bow yawed about 20° - Drift was estimated to be 16 n.m. during three days at sea anchor.

 

By and large this is probably the most important file in the Drag Device Data Base. Other than a handful of known but poorly-documented cases of commercial fishermen and some sailboats using parachutes, our knowledge about the general behavior of boats at sea anchor was sketchy until the Casanovas came alone. We didn't know if a boat would "rise to the seas," or be pulled through green water. We didn't know if the boat would roll with the punches and "yield to the seas," or stand up against them and break up. We didn't know if the boat would get "slingshotted" off the crests as the elastic rode stretched. We didn't know if the boat would "back down" on her rudder, so as to cause it to break off. We didn't know if the hardware and fittings on boats could withstand the forces involved. Well, thanks to the pioneering work of Joan and John Casanova, now we know.

The parachute anchoring system never failed on Tortuga Too, not once in eighteen years and some 200,000 blue water miles. Off the coast of New Zealand where cyclone winds were recorded at 90 mph, in a hurricane off Fiji where several other boats were lost, in 40-ft. seas in the Indian Ocean, and in a truly devastating storm off the Falklands, time and again Tortuga Too survived without damage by the correct use of the parachute sea anchor. While Lady Luck might have played a significant role in some of the other files in this database, it is clear that her role was minimal in this one. Indeed, the number of times that the parachute was used, and the broad range of life-threatening storms and heavy weather situations in which it was deployed, seem to tell us that luck had very little to do with anything here - though it goes without saying that luck always favors the wise and the well-prepared.

Despite her relatively lightweight - plywood - construction, and despite her 22-ft. beam, Tortuga Too was never in any danger of breaking up. Not once did she get slingshotted off the huge storm crests; she never went crashing through green water; the galvanized swivel did not fail; the deck fittings did not pull out. The 28-ft. diameter military parachute held and the system worked, time and time again.

Tortuga Too's worst-case scenario occurred over the shallow Burwood Bank, between Cape Horn and the Falklands. This was a "bomb" type storm development, to use the expression coined by professor Fred Sanders of the Massachusetts Institute of Technology. The term "bomb" is generally used to describe the rapid development of a secondary storm, which overtakes - and reinforces - its predecessor. In particular it describes the pressure gradient amplifications that result from the overtaking of a surface LOW by a faster moving upper altitude TROUGH, resulting in barometric pressure decreases of 24 millibars or more in a 24-hour period, as well as abruptly angled surface wind fields. This type of storm development - usually identified by high-altitude comma-shaped clouds on satellites pictures - was associated with Fastnet '79.

In the book The Parachute Anchoring System Joan Casanova describes Tortuga Too's encounter with a genuine ESW - extreme storm wave. Tortuga Too was tethered to a 28-ft. diameter C-9 parachute when an enormous mountain of curling, roaring water rose before her bows, something akin to the terrifying photographs in Coles's Heavy Weather Sailing. This sobering account should be a source of comfort to multihull sailors in particular. It is reproduced by permission of Chiodi Advertising & Publishing, publisher of Multihulls Magazine:

 

It was the type of a wave which pitchpoles yachts in these oceans, the type which every voyager sailing in the high latitudes of the Southern Ocean fears. While we watched, horrified, this monster welled up for a second time, curling over as if breaking on a beach, then roaring in foamy masses on top of Tortuga Too, covering deck and wheel house before running off into the sea once more. We were so shaken by this experience that it seemed an eternity before we regained our composure to check the boat's condition, but she was all right. In fact, Tortuga Too recovered faster than we. There was no structural damage. She had returned to her original position of facing the storm and was already climbing the next wave....

We want to stress here that no vessel, multihull, monohull or freighter, could have survived such a sea unless tethered with a long line from a sea anchor... we share this story with you only to prove how this technique can protect a craft in extraordinary circumstances. Although Tortuga Too survived this mammoth wave crashing on her deck, there was no backing down on her rudder, nor any structural damage to the hulls.

 

The experiences of the Casanovas with parachute sea anchors is so broad-based, so extensive that it has entered into the legend and nomenclature of multihull sailing. In the multihull community the name "Casanova" is synonymous with parachute anchoring, to the extent that the names "Voss" and "Pardey" are synonymous with heaving-to in the monohull community. In the course of logging all those blue water miles, Joan and "Cass" tried every conceivable heavy weather tactic known to man, including the use of makeshift drogues off the stern, but they always found themselves coming back to the bow-deployed parachute sea anchor. Multihull sailors owe a debt of deep gratitude to Joan Casanova in particular, for having the vision to see in her valuable storm experiences a responsibility to inform others. (See also her early articles in the Spring 1976, July/August 1979 and August 1980 issues of Multihulls Magazine).

Sea Anchors on Trimarans

S/T-2 Trimaran, Kismet

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KISMETS/T-2

Trimaran, Kismet

31' x 18' x 2.5 Tons

20-Ft. Dia. Parachute Sea Anchor

Force 10+ Conditions

 

File S/T-2, condensed from the writings of Randy Thomas - Vessel name Celerity II, hailing port Victoria BC, "Kismet" trimaran designed by Bill Kristofferson, LOA 31' x LWL 29' x Beam 18' 6" x Draft 30" x 2.5 Tons - Sea anchor: 20-ft. Diameter cargo parachute on 300' x 7/16" nylon three strand tether and bridle arms of 100' each, with 1/2" galvanized swivel - No trip line - Deployed in hurricane Freida in deep water in the South Pacific, with winds of 50-60 knots and seas of 30 ft. - Vessel's bow yawed 20°.

 

This file was condensed from articles by Randy Thomas and additional information provided by others, among them Bob Wilson of the British Columbia Multihull Association, to whom the author is indebted.

Celerity II, a Kristofferson-designed, light displacement Kismet 31 was en route to Kosrae from Rabaul (Solomon Islands) when she had an encounter with hurricane Freida in February 1982. As the wind and seas continued to build, Randy Thomas found options narrowing. Running off was out of the question. It would take Celerity II into a screen of low-lying atolls, and toward the eye of the storm. And Randy had once tried lying a-hull in a blow off Point Conception, California. It had been a bad experience.

With her reefed main set as a riding sail and the tiller lashed amidships, Celerity II lay quietly hove-to for a while. But the wind was building in 5-knot increments and soon it became clear to Randy that the mains'l would have to come off altogether - taken off the boom. It was time to set the parachute sea anchor. Randy had never set the chute before. With safety harnesses snapped on, he and his companion Thea carried the 20-ft. diameter parachute on deck. Crests broke over the boat as Randy crawled onto the narrow floats to shackle each end of the bridle to the heavy duty U-bolts which he had installed three feet inboard. "`Next time rig the bow bridle before you leave port,' ran my mental memo." (Writing in the article that appeared in SAIL Magazine). They dunked the chute and watched, as the boat's drift payed out the 400' of tether and bridle. But Celerity II continued to lie-ahull!

Bridle should be attached to the extreme outboard ends of the floats to obtain maximum leverage possible.

Overcome with dismay, Randy wanted to get the knife and cut the whole rig away, but Thea shouted above the noise of the wind that he should try leading the bridles off the extreme outboard tips of the floats before doing so. Randy was skeptical at first, but then decided to give it a try. He would have to unclip the two snatchblocks from the U-bolts (three feet inboard), wriggle out to the ends of the narrow floats and re-attach them to pad-eyes forward. It was a formidable struggle, but it did the trick. Celerity II immediately rounded up and began facing the seas. In his article appearing in the June 1982 issue of SAIL, Randy describes Celerity II's behavior (reproduced by permission of SAIL Magazine):

She bobbed easily over the upwelling crests, first backing swiftly, then popping upward like a suddenly released balloon. I was certain we would be buried under each seemingly perpendicular wall. No water came on deck. The bridle led perfectly, never coming into contact with either the hulls or the deck. There was no jerking at the blocks - only a gradual tension and relaxation as the nylon "springs" dissipated the heavy loads. We were anchored in mid-Pacific. We might have been anchored in a monsoon-torn harbor, except for the longer periods between each extraordinary rise and fall.

With the situation in hand they went down below and prepared a meal. Radio reception faded in and out, but they were able to piece the fragments together: tropical storm Freida had been upgraded to a hurricane, and her eye was 150 miles to the north! Just before dark Randy estimated the wind speed at about 50 knots sustained, with seas of 30 feet from trough to crest. Many of the waves were observed to be breaking heavily along their full lengths, but Celerity II had settled down into predictable cycles and seemed to be doing OK.

The night was a lonely vigil for the two. Randy writes that lying in the dark cabin they were mentally overwhelmed by the noise of the combers, rising in pitch as they approached the boat and then falling in pitch as they receded - like approaching and receding freight cars. The wind was shrieking through the rigging and the radar reflector up on the mast, creating an incessant racket that tore at their nerves. It was impossible to sleep. At dawn they were able to prepare a breakfast, and the radio informed them that the eye of the storm - packing 100 knot winds - had re-curved and was passing to the north for the second time! Thea put her head into the plastic observation bubble in the coach roof and surveyed the white seas around them. Suddenly she exclaimed she could see the parachute in the distance. As the boat climbed the next wave, Randy saw it too, "a shimmering disc, suspended like a huge jellyfish in the face of the bottle-green sea. The shroud lines reached out like tentacles, holding us safely in their grasp. We knew we were safe as long as our chute held." Well, the chute did hold, and, other than some minor damage to the trim-tab on her self-steering rudder, Celerity II emerged from her encounter with the lady Freida intact. In the same article Randy Thomas sums up his opinions:

Cruising safety depends on having options. And the parachute sea anchor can offer you a crucial alternative when the chips are down. Lying a-hull in heavy seas can result in damage, capsize, or worse aboard a light-displacement boat that is easily "tripped" by a fin keel or a submersible float. A parachute will hold such craft safely head-to-the-seas, minimizing drift and the danger of breaking crests.

Sea Anchors on Trimarans

S/T-3 Trimaran, Cross

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CROSSS/T-3

Trimaran, Cross

50' x 27' x 16 Tons

28-Ft. Dia. Parachute Sea Anchor

Force 10 Conditions

 

File S/T-3, obtained from the owner of the boat, residing in Durban, South Africa - Vessel name withheld by request, hailing port Yarmouth, England, trimaran ketch, designed by Norman Cross, LOA 50' x Beam 27' x Draft 6' x 16 Tons - Sea anchor: 28-ft. Diameter C-9 military class parachute on 500' x 3/4" nylon braid tether and bridle arms of 80' each, with 5/8" galvanized swivel - Full trip line - Deployed in an Atlantic storm in deep water south of Tristan Da Cunha with sustained winds of 50 knots and seas of 30 ft. - Vessel's bow yawed 20° - Drift was estimated to be 12 n.m. during 36 hours at sea anchor.

 

South African safety expert, yachtmaster, instructor and Intec Maritime Academy principal Henton Jaaback had heard about the Casanovas' pioneering work. He acquired a military parachute, which he ended up loaning to the owner of this passage-bound trimaran. On her way to Rio from Cape Town the trimaran ran into a horrendous storm south of the island of Tristan da Cunha. Exhausted, the owner and his wife deployed the parachute according to the Casanovas' guidelines. It pulled the three bows into the huge seas and kept them there for 36 hours - through the worst part of the storm. After the 36 hours there was a jerk, the bows fell off the wind, and the big multihull lay beam to the seas, drifting downwind. It is the owner's opinion that the galvanized swivel in the system seized - failed to rotate, though the 3-strand rope used for the bridle arms is suspect as well (3-strand will torque under load). At any rate when he pulled the lines back on board, all that remained were the two bridle arms of about 60 ft. each, twisted around each other and their ends unraveled. The full trip line had snapped at the same time, so they lost everything, hardware, swivel, tether, parachute and all.

Galvanized swivels have always been a source of concern to your author, though one looks at the Casanovas' file and sees that they never had a problem with theirs in eighteen years of cruising and storm use. The problem with these swivels lies in the galvanic process, which results in an acid-etched coarse surface, liable to stick or "gall" under load. Even so, the swivel - if of good American or Japanese make - usually gets a chance to rotate during slack cycles, as born out by many other files in this database. Moreover there are excellent stainless steel swivels on the market today.

Why do parachutes rotate under load? They may do so because of inconsistencies in fabrication, or shroud lines that are not precisely equal in length. But mostly they rotate because of the ratchet effect produced by the overlapping of the panels. These panels, shaped like pie wedges, have to be sewn together to form the circular shape of the canopy. The edge of the first panel is laid over the edge of the second and sewn, the edge of the second panel is laid over the edge of the third, etc., the radial seams being over, over, over, and this is where the ratchet effect crops up. To do away with this built-in cause of rotation one has to stagger the fit of the seams. The edge of the first panel is laid over the second and sewn, but the edge of the second panel is laid under the third, etc. Over, under, over, under. The parachutes that are used to slow down supersonic aircraft on the runway are of staggered fabrication. You won't see them spin.

CANOPY
Canopy panels

The panels on Para-Tech sea anchors are now sewn in such a way as to be spin-neutral, although swivels are still a good idea. Here is a transcript of the DDDB feedback provided by the owner and his wife:

 

Swivel on bridle galvanized iron 16 mm - swivel on parachute 16 mm also. The bridle was attached to the swivel of the main line with two shackles. Main line 20 mm "multiplait." Bridle was 25 mm nylon 3-strand rope. After recovering the remains of the bridle we saw we had lost the two shackles and the swivel. The remains of the arms of the bridle were unraveled & twisted around each other - everything else was lost. We have been informed that galvanized swivels apparently lock under strain....

The trip line also snapped when we lost the para-anchor. This was at about 3 pm (we felt a jerk). We rushed into foul weather gear and on deck.... When we started up the engine and tried to find the "rig," the wind was so strong the boat could make no headway - also the seas were white, so the [white] buoy was impossible to see! A red buoy would perhaps show up better, even though we could not have motored to get it....

Some hours after we lost the para-anchor, after broaching dangerously south of Tristan da Cunha, we decided to use a drogue to slow the boat and eliminate broaching. We were bare-pole doing 5-6 knots and descending the slope of waves at 12-13 knots. The drogue consisted of 150 ft. of "multiplat" 20 mm. rope plus 33 ft. of 1/2" chain with 4 knots to make more vortex [turbulence]. All the above was attached to a bridle of 30 ft. [each arm].... We used the engine [in conjunction with the drogue] at the minimum, about 1000 revs, that gave us a speed of approx 4-5 knots and maximum speed in descending wave slope of 7-8 knots and no more broaching.

We needed the engine to keep enough steering power. We had a 3-blade fixed prop that spoiled the efficiency of the rudder; I think we lost about 50% efficiency! But we used the autopilot without any problem and we really appreciated the work of the drogue in straightening the boat each time at the beginning of a broach. The bridle was fixed to two sampson posts of 4" square oak, fixed to the keel of each float. The wind was then about 40 knots, with big breaking seas for about 24 hours.

We were very surprised by the efforts [loads] imposed by the drogue and also by the parachute anchor and we don't think that normal cleat-type fitting would have lasted under the strain....

We now have two para-anchors.... We honestly feel we would not sail without one now. Our experience around Tristan, and the knowledge that we were safe and could ride out a storm, has made this indispensable.

Sea Anchors on Trimarans

S/T-4 Trimaran, Condor

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CONDORS/T-4

Trimaran, Condor

40' x 28' x 3 Tons

18-Ft. Dia. Sea Anchor

Force 7-8 Conditions


File S/T-4, obtained from Jack Hunt, Apollo Beach, FL. - Vessel name Crystal Catfish IV, hailing port Apollo Beach - Trimaran, designed by Condor Ltd., LOA 40' x Beam 28' x Draft 8' (20" board up) x 3 Tons - Sea anchor: 18-ft. Diameter Para-Tech on 400' x 1/2" nylon three strand tether and bridle arms of 80' each, with 5/8" galvanized swivel - No trip line - Deployed during passage of low system in deep water in the Gulf of Mexico about 125 miles WNW of Tampa with winds of 30-40 knots and seas of 15 ft. - Vessel's bow yawed 10° - Drift was estimated to be about 2 n.m. during 12 hours at sea anchor.

 

Jack Hunt is a veteran of the 1980 and 1984 OSTARs (Observer Singlehanded Trans-Atlantic Race) in which he sailed a 31-ft. monohull named Crystal Catfish III. After making the switch to a lightweight, fast multihull, Jack ended up using a Para-Tech sea anchor during the 500-mile single-handed qualifying run, in preparation for the 1988 OSTAR. In a related article which appeared in the January/February issue of Multihulls, Jack describes conditions in the Gulf of Mexico in the winter as "a battleground of warm and cold fronts, locked in fifteen-round bare-knuckled battles for supremacy, much like the English Channel in June, except the waves in the Channel have the decency to come from the same direction as the wind." Here is a transcript of the DDDB feedback your author obtained from Jack:

 

Two things caught me by surprise in the twelve hour winter ride [at sea anchor] in the Gulf. First, how much stretch there is in nylon rode. Chafe protection is a must. Second, the "G-forces" which result from the boat being lifted up on a wave top (increased G-force) and then let down into a trough (reduced G-force), much as one would feel on a roller coaster. These forces are a characteristic, I suspect, of the lightweight multihull configuration, having nothing to do with the para-anchor and not at all a problem, just surprise. Because I am alone I do not use a trip line; not enough hands. Instead, I winch the rode in until the para-anchor is within reach with a boat hook and then pick up a shroud line. All of which nets me quite a mess hurriedly stuffed into a bag on a trampoline, so I can get back to tending the suddenly underway boat. Re-folding the chute for its next use presents me with the "one-legged sailor at an ass-kicking contest" scenario. Consequently I have acquired a parachute for use in between the time I haul out the para-anchor and can get it re-folded, if something should develop. The [aerial] parachute is not nearly as rugged as the para-anchor, however, so I remain motivated to work out a more reliable re-folding routine.

The only question remaining for me is, "why didn't I use a para-anchor all those years I had a monohull?" Probably had to do with the false heroism of getting the hell kicked out of me and my boat while hove-to. I should have had this para-anchor years ago.

Sea Anchors on Trimarans

S/T-5 Trimaran, Newick Derivative

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VALS/T-5

Trimaran, Newick Derivative

30' x 25' x 2 Tons

5-Ft. Dia. Sea Anchor

Force 9 Conditions

 

File S/T-5, obtained from the owner of the boat, residing in Falmouth, MA. - Vessel name withheld by request, hailing port Falmouth, design derived from the Newick Val 31 concept (lightweight, open wing ocean racing trimaran), LOA 30' x Beam 25' x Draft 8' x 6" (2' 3" board up) x 2 Tons - Sea anchor: 5-ft. Diameter Shewmon on 200' x 5/8" nylon three strand tether and bridle arms of 50' each, with 1/2" galvanized swivel - No trip line - Deployed in a gale in deep water within the Gulf Stream with winds of 45-50 knots and seas of 12 ft. - Vessel's bow yawed 10° - True drift was undetermined due to the Gulf Stream.

 

This lightweight Val-class racing trimaran was sailing back from Bermuda to her home port of Falmouth when she ran into a gale within the Gulf Stream. The skipper deployed a 5-ft. diameter Shewmon sea anchor, which pulled the three knife-like bows into 12-ft. confused seas, and kept them safely there for a period of 18 hours. Several snatch blocks were used to bring the bridle ends to cockpit winches. This enabled the skipper to work the bridle from the safety of the cockpit. He found it necessary to freshen the nip once every hour or so - two turns on the winches to shift the wear points and reduce localized chafe. The large daggerboard - drawing 8' 6" when fully lowered - was raised about two thirds of the way up, leaving about three feet of board sticking out of the bottom to keep the hull's center of lateral resistance sufficiently forward. The tiller was lashed amidships.

The bridle was led off the main hull and the tip of the port float only. The beam of the yacht being 25 ft., this "half-bridle," extending from a 12½ ft. base, was evidently enough to provide the leverage needed to keep the trimaran facing into the seas. In general your author is opposed to "half-bridles," however. Along with other safety experts, your author feels that the multihull bridle should make full use of the leverage afforded by the maximum beam of the yacht. The wider the base of the bridle, the greater the leverage - and the more positive its influence in terms of vessel alignment.

Sea Anchors on Trimarans

S/T-6 Trimaran, Pivercraft Nimble

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NIMBLES/T-6

Trimaran, Pivercraft Nimble

30' x 18' x 3 Tons

12-Ft. Dia. Sea Anchor

Force 5-6 Conditions

 

File S/T-36 obtained from John H. Baldwin, South Orleans, MA - Vessel name Goodspeed, hailing port South Orleans, trimaran designed by Arthur Piver, LOA 30' x Beam 18' x Draft 30" x 3 Tons - Sea anchor: 12-ft. Diameter Para-Tech on 400' x 1/2" nylon three strand tether and bridle arms of 45' each, with 1/2" galvanized swivel - Full trip line - Deployed in frontal trough in shallow water (20 fathoms) about 30 miles off Beaufort, North Carolina, with winds of 25 knots and seas of 6 ft. - Vessel's bow yawed 10° - Drift was 3 n.m. during 10 hours at sea anchor.

 

This file shows how a sea anchor can be used to "keep the sea" in terms of drift control. Groundings are among the fourteen major types of statistical accident data published in the Coast Guard's Boating Accident Reports. There are hundreds of groundings a year. Many a seaworthy yacht has survived the storm offshore only to run aground and be declared a total loss because of an error in navigation, or engine problems, or rudder problems. Quite often the needless loss occurs because of crew fatigue and impatience. The sight of the harbor range lights in the murky night is a temptation that sea-weary sailors would do well to resist, especially if it is a strange, windy harbor with a difficult, narrow entrance.

The scenario is all too familiar. The crew members have been cooped up in the heaving boat for days, maybe weeks. Likely exhausted, wet, cold, hungry and deprived of sleep, they can scarcely wait to set foot on dry ground, indulge in a steaming hot shower, inhale a couple of juicy hamburgers and climb into a comfortable, dry bed. So they decide to try to risk it - and run aground. Vessels equipped with sea anchors are better able to resist this temptation, since they can use the parachute to stand off until daylight. Instead of risking entry on a windy night, or trying to anchor the boat over a coral bottom with surf booming a hundred feet away, one can stand off a mile or two and use the parachute as an "offshore anchor," which is what your author used to do in the windy channels of Hawaii.

Goodspeed is an original Piver Nimble trimaran, used as a commercial fishing vessel by John Baldwin. Baldwin is offshore for long periods of time and often heaves to the parachute for sea layovers. He also uses it to stand off outside strange harbors, waiting for daylight. Transcript:

We deployed the sea anchor on the fourth day out.... There was no storm or nautical emergency. My crew mate Chris and I had been on a spinnaker run in the Gulf Stream, heading for Beaufort, North Carolina. Dusk found us still 30 miles from Beaufort with a freshening breeze from the south. Six months earlier we had learned a hard lesson: don't attempt to enter unfamiliar harbors at night. Tired and half seasick, we were approaching St. Mary's Inlet on the Georgia/Florida border. It was 4 am and we had been sailing all night on the working jib with the wind increasing from the north. "If I can find a light I'm going for it," I told Chris. I didn't have a large-scale chart and was nervous. Chris found the Waterway Guide and on the last page read "the stone jetties of the entrance are awash at half-tide, constituting a hazard." A quick check with the tide charts in Eldrige and sure enough, it was nearing half tide. We spent a hard couple of hours jibing and standing off, until dawn brought us in with the fishing boats.

Now, six months later, armed with our new parachute sea anchor, we doused the spinnaker, then hove-to the sea anchor with no trouble. Fishermen off the Pacific coast routinely deploy sea anchors at night. They know, and I know too, that nothing beats a sea anchor for peace of mind and a good night's sleep.

When using his sea anchor for station keeping offshore, John Baldwin has a unique way of obtaining the bridling advantage, without actually using a dedicated bridle (see image below). He gives the main tether (A) a few turns around the starboard float cleat, before securing it to big anchoring cleat on the main hull. He then brings a single, short utility line (B) from the port float and bends it onto the main rode by means of a rolling hitch. This way, even if the rolling hitch slips - he says it never has - throwing the turns off the starboard float will put the main rode back on the center hull. Of course, the purpose of this arrangement is to allow variable rode lengths for multihulls, in non-storm applications.

Setting up a variable length bridle
Setting up a variable length bridle
Sea Anchors on Trimarans

S/T-7 Trimaran, “Rose-Noëlle”

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GLENNIES/T-7

Trimaran, "Rose-Noëlle"

41' x 26' x 6.5 Tons

24-Ft. Dia. Parachute Sea Anchor

Force 8-10 Conditions

File S/T-7, obtained from John Glennie, New Zealand - Vessel name Rose-Noëlle, hailing port Nelson, New Zealand, trimaran designed and built by John Glennie, LOA 41' x Beam 26' x Draft 3' x 6.5 Tons - Sea anchor: 24-ft. Diameter military chest reserve parachute on 300' x 3/4" nylon three strand tether and bridle arms of 40' each, with 1/2" galvanized swivel - Full trip line - Deployed in a gale in deep water about 150 miles southeast of the East Cape of New Zealand with winds of 40-60 knots and seas of 20 ft. - Vessel's bow yawed 10° - Fouled trip line collapsed the parachute after 10 hours, allowing the trimaran to lie a-hull and be capsized by a rogue wave - Crew survived 118 days adrift inside the inverted hull.

 

On 4 June 1989 the trimaran Rose-Noëlle capsized some 140 miles east of the Wairapa coast of New Zealand. The crew of four spent 118 days adrift inside the upturned hull. The incident subsequently became a source of some controversy, leading to an investigation by the New Zealand Ministry of Transport. John Glennie's exclusive story was first published in the November 1989 issue of New Zealand Yachting. Later, John wrote a book about the ordeal called Spirit of Rose-Noëlle.

John Glennie is an institution in the land of Down Under. New Zealand and Australian magazines have referred to him as Free Spirit of the Pacific. John and his brother David started out by building a 35' Piver Lodestar trimaran in their Father's Marlborough farm shed in America. They named it Highlight and sailed away. After spending eight years roaming all over the Pacific, John and David wound up in Australia, where they worked on and delivered many famous boats, including Mike Kane's Spirit Of America, a Kraken 55 trimaran of Lock Crowther design.

Glennie's own boat, Rose-Noëlle, took nineteen years of intermittent work to build and launch. John sailed it to the Great Barrier Reef, then across the Tasman Sea to New Zealand, where he gained boat-building work at Paremata, working with the brother of New Zealand's America's Cup helmsman, David Barnes. Every cent that he earned went into equipping Rose-Noëlle for self-sufficiency on high seas. Innovative rigging, water still, solar panels, radios, radar, etc., and a 24-ft. diameter parachute sea anchor.

Rose-Noëlle set sail from Picton New Zealand on June 1st (winter Down Under), headed for warm waters and Tonga. The crew consisted of John Glennie, Philip Hoffman, Rich Hellriegel and Jim Napelka. On the third day out they ran into a southerly gale and for a while used a Sea Squid (bullet-shaped Australian plastic drogue) to slow the boat down. Later they stopped the boat and deployed the parachute sea anchor. It pulled the three bows of Rose-Noëlle into 20-ft. seas and kept them there for the next ten hours.

The full trip line, probably left hanging loose in the sea, must have fouled with the parachute because sometime after those ten hours the trimaran began to yaw increasingly from side to side, until finally she was lying a-hull. It was night and little could be done. An hour or so later, the crew heard the approach of a great roaring noise, much like that of a huge - Hawaiian - surf wave. The rogue wave hit the boat broadsides and rolled her over very quickly. In the article that appeared in New Zealand Yachting Glennie stated that just before the capsize the wind had eased and he was concerned that without the wind "regulating" the seas, two or three waves might "ring hands and turn into rogues."

After the capsize it took the crew a while to settle down to the business of survival. Wrote Glennie, "I had to keep their hopes up and get them over the shock of the first stage. If people give up, they die." Eventually they all adapted, surviving the next 118 days adrift inside the inverted hull of the trimaran. There was plenty of food left inside, and the problem of fresh water was solved when John devised a system for collecting and storing rain water. From then on it was patience and perseverance, despite numerous gales, saltwater sores, and the occasional brawl that one might expect in such dire and cramped circumstances.

The inverted trimaran drifted "all over the place." It is estimated that she covered, ignominiously, a journey of nearly 2,000 miles, during which the cramped crew experienced somewhere between 17-20 gales - an average of one every week! And astonishingly enough, four months after the Royal New Zealand Air Force planes had given up the search for Rose-Noëlle she washed back up unto Great Barrier Island, at the edge of the Hauraki Gulf, the well-populated sailing area of New Zealand. Transcript of hand-written notes that accompanied John Glennie's feedback:

The para-anchor worked well and I was most impressed till it fouled.... The trip line fouled the chute and with the chute partially collapsed we lay a-hull.... The wave was so big that it would have rolled the Cutty Sark! They [rogue waves] are out there. I think three waves got together, so it was probably 60 feet high. I saw a similar 60-ft. vertical wall of water in 1968, mid-winter, 43° south, below Tahiti. Water was running down its face and I remember the noise it made as it came towards us.... Next time I won't use a trip line. I could have got the chute back in with the electric capstan in the calm after the storm.

 

Full trip lines should be kept FAIRLY TAUT so they do not hang down in the sea and foul the rode and parachute.
Full trip lines should be kept FAIRLY TAUT so they do not hang down in the sea and foul the rode and parachute.

A reminder that the Casanovas used full trip lines for eighteen years with seldom a foul-up. According to John Casanova, the trick is to have a small swivel at the float, and keep the trip line fairly taut - no excess slack hanging loose in the sea to foul with the parachute or rode. Bear in mind, also, that if the wind force increases the main rode will elongate, requiring that the full trip line be slackened off accordingly (otherwise it may trip the canopy). By checking the trip line tension on a regular basis, one can tell if it is too loose, or too tight. One should also use the binoculars to keep an eye on the big red float itself. If it is behaving awkwardly - as though it had hooked onto a big fish - it may mean the trip line is too tight and needs to be slackened off a little.

Sea Anchors on Trimarans

S/T-8 Trimaran, Cross

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CROSS42S/T-8

Trimaran, Cross

42' x 23' x 7 Tons

18-Ft. Dia. Sea Anchor

Force 9-10 Conditions

 

File S/T-8, obtained from Daniel A. York, Costa Mesa, CA. - Vessel name Gold Eagle, hailing port San Francisco, trimaran designed by Norman Cross, LOA 42' x Beam 23' x Draft 4' x 7 Tons - Sea anchor: 18-ft. Diameter Para-Tech on 400' x 5/8" nylon braid tether and bridle arms of 60' each, with 5/8" stainless steel swivel - No trip line - Deployed in gale-force winds in shallow water (25 fathoms) about 15 miles west of the Nicoya Peninsula (Costa Rica) with winds of 45-60 knots and seas of 10 ft. - Vessel's bow yawed 10° - Bearings taken from three shore lights indicated no noticeable drift during five hours at sea anchor.

 

This file is about a 42-ft. trimaran that used an 18-ft. diameter Para-Tech sea anchor to stand off a lee shore against the sudden onslaught of 40-60 knot winds. Gold Eagle was sailing to Puntarenas, Costa Rica, from Corinto, Nicaragua. In the evening of 22 May 1990 she was about fifteen miles offshore, about to clear Cape Blanco on the Nicoya Peninsula, when the wind came up out of nowhere. Incidentally, this is a common occurrence on the Pacific side of the Central American coast. Whether caused by a massive high pressure cell over Texas funneling air through gaps in mountains, or by the seasonal migrations of the Inter Tropical Convergence Zone, it is something one should always be prepared for in Central American waters. Transcript:

Wind (45 knots) came up very fast at approximately 2000 hrs. I rushed forward to drop the club-footed jib (already reefed). The aft reef grommet tore out along with 3' of sail before I could drop it. Under full power (40 hp. Mercedes Diesel with 18" diameter 3-bladed prop) boat was being blown backward so fast that the rudder was trying to jam hard over. Seas starting to come over port beam after engine secured as it was overheating. Dropped 18-ft. diam. para-anchor. Bridle shackle almost hung up on port ama cleat, but I cast it free just before strain on bridle. Boat immediately swung into wind and seas. Seas very short and steep as boat climbed and fell off crests.

I was concerned we'd be blown to shore, but over the 5 hour period I took bearings from three shore lights (360°, 125°, 100°) with no noticeable drift. Winds maintained 50-60 knots for approx. 1 or 1.5 hours, then lowered to approx. 40-45. After five hours winds dropped to only 10 knots. Another trimaran, returning to Long Beach after participating in a trans-Atlantic race, had trouble with jammed sail track slides and was dismasted in the same blow. My sea parachute is one of the few items I purchased that performed as advertised and no defects or surprises. I appreciated the quality and the performance more than I can express. Wouldn't leave port without it ever.

 

Sea Anchors on Trimarans

S/T-9 Trimaran, Condor

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triple_shockS/T-9

Trimaran, Condor

40' x 28' x 3 Tons

18-Ft. Dia. Sea Anchor

Force 10 Conditions

 

File S/T-9, obtained from Phil Herting, Coconut Grove, FL. - Vessel name Triple Shock, hailing port Norfolk VA, trimaran designed by Condor Ltd., LOA 40' x Beam 28' x Draft 8' (20" board up) x 3 Tons - Sea anchor: 18-ft. Diameter Para-Tech on 400' x 5/8" nylon braid tether (no bridle) with 5/8" stainless steel swivel - Full trip line - Deployed in a gale in deep water about 120 miles west of Miami with winds of 50 knots and seas of 15-20 ft. - Vessel's bow yawed 45° (without bridle) - Drift was estimated to be 15 n.m. during 7 hours of deployment.

Triple Shock was on her way back to Miami from Jamaica, after participating in the Miami-Montego Race. The wind had been building for some time when the aluminum rudder cage split, leading to complete loss of steering control. The para-anchor was deployed to stabilize an emergency situation. No bridle was used, just a single rode leading off the main hull, as a result of which the bow would yaw considerably off the wind. With the weather deteriorating, a nearby Coast Guard vessel was asked to render assistance. Delivery skipper Phil Herting said that the seas were so large that the 110' CG cutter, Madagorda, would periodically disappear from view in the troughs. Transcript:

 We were NNE of Great Issacs in deteriorating conditions when the aluminum fabricated rudder cage split. Upon breaking, the boat rounded up and then stalled. We immediately dropped the main and rolled up the balance of the jib. At that point we deployed the para-anchor. This device was utilized to stabilize an emergency situation and was deployed to ride out some bad weather. Because of the immediacy created out of the breakage we had to deploy it as fast as we could and with what line we had immediately available. For this reason the first line tied to the para-anchor was a 1/2" pre-stretched Dacron backup spinnaker halyard.

This immediately proved to be a mistake. The shock load transmitted back through the line was unbelievable. Realizing our mistake we then attached 250' of 3/4" three strand nylon. Though the nylon reduced the shock loading, it created another problem. I elected not to attach the second rode to a bridle because I wanted to save that for the tow from the CG cutter. So we led the rode through the bow chock to a primary winch. This enabled us to adjust the line when replacing chafing gear. And the chafe was the problem. Because the distance from the winch to the chock was so great, it created a longer spring and chafe area on the line. In retrospect, I should have deployed the nylon rode first and then had a Dacron tail. This would have minimized the chafe at the chock.

The Madagorda, the 110' cutter that came to our assistance, said that our rescue was done in the worst weather in which they had ever attempted one. They did a phenomenal job, though it did take 3 hours to get us a heaving line. One reason for this was the fact that the parachute was sitting right where they wanted to position themselves when getting us the towline.

What are you going to do? I hate to think of the situation if we had not had the para-anchor with us. It should be considered a vital piece of gear when making any substantial offshore passage.

Sea Anchors on Trimarans

S/T-10 Trimaran, Searunner

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BROWN31S/T-10

Trimaran, Brown Searunner

31' x 18' x 2.2 Tons

12-Ft. Dia. Sea Anchor

Force 7-8 Conditions

 

File S/T-10, obtained from Donald Longfellow, Garden Grove, CA. - Vessel name Take Five, hailing port Ventura, Searunner trimaran designed by Jim Brown, LOA 31' x Beam 18' 6" x Draft 5' (2' 6" board up) x 2.2 Tons - Sea anchor: 12-ft. Diameter Para-Tech on 300' x 7/16" nylon braid tether and bridle arms of 45' each, and 1/2" galvanized swivel - Full trip line - Deployed in Papagayo conditions in shallow water (25 fathoms) about 20 miles off the coast of Nicaragua with winds of 30-40 knots and choppy seas of 6-8 ft. - Vessel's bow yawed 10° - Drift was estimated to be 3 n.m. during 6 hours at sea anchor.

 

Papagayo winds can come up unexpectedly. They are caused by an intensification of the trade winds in the southwestern Caribbean, blowing offshore through narrow gaps in the mountains of Central America, setting up a short, nasty chop that may run at a 30-50° angle to the predominant wave train. The real difficulty for small craft is not the size, but the steep and confused nature of the seas. Papagayos can last for a few hours, subside slowly, then come back up again. They are most prevalent from December to March. The name Papagayo comes from the Gulf of Papagayo - northern Costa Rica - where they probably blow the hardest. Their southern limit is fairly distinct, being about 10 miles south of Cabo Velas in Costa Rica. The Papagayo is harder to predict than its cousins to the north, the intimidating Tehuantepeckers of the Gulf of Tehuantepec (Mexican isthmus) and the Santa Anas of Southern California. The owner of Take Five has equipped her with a number of drag devices, including a Galerider. On 29 January 1991 he deployed a 12-ft. diameter sea anchor to cope with Papagayos. Transcript:

Because the wind was coming out of the breaks in the coastal mountains it was blowing 30 degrees off the direction of the primary wave track (120° magnetic). Adjusting the length of one bridle arm didn't rotate the boat sufficiently so I re-led the starboard bridle arm to a snatch block near the stern of the starboard float. This allowed the boat to face into the large waves coming from farther down the coast, which I considered more important than facing directly into the wind. The centerboard was up but side-to-side yaw wasn't a problem. Despite the atrocious looking sea state I eventually noticed that the boat decks were dry and, except for an occasional errant wave slapping the hull, the boat was quite comfortable. Drift was more than what I've experienced on other occasions that I've used the para-anchor. Perhaps there was a current present or perhaps it could be attributed to turning the hull 30 degrees to the wind.