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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.

Drogues on Monohulls

D/M-6B Monohull, Ericson

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ERCSON25D/M-6B

Monohull, Ericson

25' x 3 Tons, Swing Keel

Jordan Series Drogue

Force 8 Conditions

 

File D/M-6B, obtained from Gary Danielson, St. Clair Shores, MI. - Vessel name Moon Boots, hailing port Detroit, monohull, designed by Bruce King, LOA 24' 8" x LWL 20' 10" x Beam 8' x Draft 4' (27" keel up) x 3 Tons. Drogue: Galerider deployed in Force 8, mid-Atlantic - vessel required constant steering.  Jordan series drogue (88 x 5" cones on 300' x 1/2" nylon braid rode) - Deployed in a gale in deep water about 500 miles east of the Bahamas with winds of 35-45 knots and seas of 9-14 ft. - Vessel's stern yawed 10° - Drift was about 10 miles during 36 hours of deployment.

 

This file updates the previous one. Gary Danielson's Lake Huron evaluations took place in 1988. In 1991 he sailed Moon Boots across the Atlantic and back. He had occasion to use the Galerider and the series drogue in a number of Force 8 gales. In the first mid-Atlantic gale he used the Galerider and found that it greatly enhanced steering control in 15-ft. seas, but left to itself (while he was resting down below) it would allow the stern of the boat to yaw too much - 40° off to each side at times. In the second Force 8 gale (600 miles from the British Isles and 15-ft. seas again) he used the series drogue and it kept the stern of the boat snubbed into the seas and, in taking total control of the situation, allowed him to remain down below and get much needed rest. Danielson sailed Moon Boots back across the Atlantic singlehanded in March 1991, re-tracing Columbus' route from the Canaries to San Salvador in the Bahamas. En route he ran into another Force 8 gale. Transcript:

The only heavy weather of the trip occurred about 500 miles east of San Salvador, Bahamas. As my course was due West at that point, it meant the wind was right on the nose. At 25-30 knots Moon Boots can't sail upwind effectively any longer. Once the wind got to the low 30's I knew I'd have to put out a drogue. I decided to use the Jordan style series drogue rather than the Galerider because I didn't want to lose any of the ground I'd already gained and the Jordan is a much better "anchor" than the Galerider. In fact, that was pretty much how I decided which one to use on the prior trip also. In any event it did an outstanding job of keeping the stern into the waves and of limiting drift to almost nothing (10 miles in 36 hours, less any westerly drift from possible currents). I had changed the 15 lb. mushroom at the end to a 5 lb. weight and that helped the Jordan to ride a bit more horizontal (but still below the surface). The only problem was that the boat had been broken into in the Canaries and the inside lock for the main hatch had been damaged (the hatch fully closed, just couldn't be secured shut). As you probably know, the Jordan drogue exhibits a tremendous pull at all times. The transom of Moon Boots had been beefed up specially because of this, as had the hatch and the hatch boards. And a good thing too, because every so often a wave would completely go over Moon Boots (I could see solid water as I looked out the side ports).

The problem was that at times these waves would slide the main hatch 2-3' forward. Note that the hatch top itself was custom made of wood, weighted almost 75 lbs., and slid very hard on its track as it did not sit on rollers or cars of any type (just slid on metal tracks). It always took an effort with both hands to slide it open or shut. But these waves would slam it open and at the same time 30-50 gallons of water would pour in, (this happened 9 times in 36 hours). Therefore anyone using this style drogue had better have prepared the stern of his boat properly.

It has occurred to me that since the Jordan style drogue has a constant and continuous pull, it could make a superior sea anchor (off the bow) if sized properly for a given boat. It wouldn't work on Moon Boots as a sea anchor, but any boat that behaves OK with a sea anchor would probably be even safer with a Jordan style. I now believe, more than ever, that my solo Atlantic passages on Moon Boots could not have been accomplished safely without the drogues.

 

Drogues on Monohulls

D/M-6A Monohull, Ericson

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ERCSON25D/M-6A

Monohull, Ericson

25' x 3 Tons, Swing Keel

9-Ft. BUORD, 30" Galerider & Series Drogue

Force 4-5 Conditions

File D/M-6A, obtained from Gary Danielson, St. Clair Shores, MI. - Vessel name Moon Boots, hailing port Detroit, monohull, designed by Bruce King, LOA 24' 8" x LWL 20' 10" x Beam 8' x Draft 4' (27" keel up) x 3 Tons - TESTS OF: 9-Ft. Diameter BUORD, 30" Galerider, Jordan Series Drogue - Deployed for evaluation purposes during passage of frontal trough in shallow water (9 fathoms) on Lake Huron with winds of 25 knots and seas of 6-8 ft.

 

Prior to sailing his Ericson 25 across the Atlantic Gary Danielson tried out three different drag-device concepts: A 9-ft. diameter BUORD parachute off the bow, a 30-inch Galerider drogue off the stern, and a Jordan series drogue off the stern (88 x 5-inch diameter cones spliced into 300 ft. of braided 1/2" nylon towline at 20" intervals, with a 15 lb. mushroom anchor at the very end to keep the array well-submerged).

To make his investigation as reliable as possible Danielson did all of the testing on a single day, in constant conditions. The crew for this evaluation was along solely to take measurements and record data. The tests were conducted in November 1988 on Lake Huron. On the day of the tests the sustained wind speed varied between 20 and 25 knots with gusts of 30 knots. The waves varied between 6 and 8 feet.

One of Danielson's preconditions was that the swing keel be up and out of harm's way on this particular boat. With the keel raised he found that the 9-ft. BUORD parachute would not pull the bow of Moon Boots into the seas in a satisfactory manner. It yawed up to 50° off to each side. This is not too different from the experience of Harley Sachs in file S/M-11, where the bow of Gamesmanship yawed 30-45° off to each side when the keel was retracted, but only 10° when it was lowered. Transcript:

 

Sea Anchor: A 9 foot sea anchor was deployed over the bow attached to 300 feet of 3/8" braided nylon rode. The centerboard and rudder were both raised and all sails were lowered for this test. The sea anchor was very easy to deploy and there was no shock to it when it grabbed hold of the boat. It did an extremely good job of keeping the boat in place as sternward drift through the water ranged from .25-.75 knots. The problem was that the boat was yawing through an arc which totaled almost 100 degrees (putting the bow of the boat almost 50 degrees off the wave). It was yawing very slowly from side to side so that there were lengthy periods (60 seconds) where the bow of the boat was as much as 50 degrees from the wave direction.

Since the boat spent so much of its time not being bow-on to the waves it rolled quite heavily (in excess of 20 degrees) and relatively quickly. Had the conditions been more severe, this could have proved to have been dangerous. The rode was then shortened to 150 feet of scope to see what effect that would have on the yawing of the boat. Repeated measurements showed no substantial variation in yaw even with the shortened scope. The sea anchor was very difficult to retrieve as Moon Boots has no anchor windlass on the foredeck and as no trip line had been attached to the sea anchor.

 

A BUORD is a porous small parachute issued by the Bureau of Ordnance
A BUORD is a porous small parachute issued by the Bureau of Ordnance

 

Galerider: The next item tested was the Galerider drogue. This was set from the stern utilizing a 30 foot 1/2" braided tether which was connected to each of the stern quarters of the boat and then attached to a 150 foot 3/8" braided nylon rode. Initially the Galerider was utilized with no sail up, the centerboard and rudder both retracted. The Galerider drogue had a steady and constant pull and did not jerk when it was deployed... it held the boat to a total yaw of 10° (5° per side). The boat rolled (vertically) no more than 10-12° to a side. As well, it rolled much more slowly than it did with the sea anchor out. The Galerider was running below the surface, but only by about 5 feet. Therefore, in heavier conditions it may be somewhat more susceptible to surface wave action. It did not pull the stern down much at all and gave the boat, overall, a very nice ride.

Next, the rudder was lowered and allowed to swing free and the centerboard was lowered while the Galerider was still out. It was noted that the boat then yawed through a total of about 70° (35° per side). The boat still rolled very little and did so slowly. Next, a small jib sail was raised to see how the boat sailed with the Galerider out. The boat could be sailed through a total arc of 90° (45° per side). The boat speed ranged from 2.5 to 4 knots. There was no tendency whatsoever for the boat to surf and, of course, at these speeds it was very responsive to the helm. The Galerider was particularly easy to retrieve as the rode with which it had been deployed was wrapped around a cockpit winch and winched back aboard.

Galerider drogue produced by Hathaway, Reiser and Raymond
Galerider drogue produced by Hathaway, Reiser and Raymond

 

 

Series Drogue: The Jordan style series drogue was then deployed over the stern using the bridle to each of the quarters of the boat and attached to the 300 ft. rode (with cones)... the centerboard was up, the rudder was up and all sails were lowered for this test. This drogue was easy to deploy and caused no shock loading when it began to take effect. The Jordan style drogue appeared to sink very deeply into the water and, in fact, created a substantial downward as well as rearward pull on the boat. Consequently a number of waves washed in over the transom of the boat while the Jordan drogue was deployed. The Jordan drogue slowed the boat so that the average speed was between 0 and .25 knots.... The boat yawed a total of 10° (5° per side). The boat rolled very little, only 10-12° per side, and did so slowly. The series drogue was easier to retrieve than the sea anchor (without any trip line) but more difficult than the Galerider. It was easier than the sea anchor because every few feet of rode that were retrieved resulted in one less cone being in the water to create drag and therefore the drag continued to be reduced as the rode was brought in. The difficulty with retrieving the Jordan style drogue is that it cannot be retrieved utilizing winches because the cones get tangled up when a winch is used so that retrieval can only be done by hand....

The Jordan Series Drogue consists of dozens of tiny cones spliced into the long rode
The Jordan Series Drogue consists of dozens of tiny cones spliced into the long rode

 

CONCLUSIONS: In the moderate conditions of the test the Galerider was definitely the best product of those which were tested. Its advantages are its small storage space, its ease of deployment and retrieval.... It has the additional benefit of having enough drag that the boat can be actively sailed, but will not surf, should you find the wind blowing in a favorable direction. It would be useful if repairs were needed since it stops the boat from rolling. The Galerider is also good in that it does not seem to pull the cockpit down (which would make it vulnerable to breaking waves). The concerns that I have are that it may not ride deep enough to avoid wave action in heavy weather (resulting in a possible loss of drag) and it is possible that it may not offer enough drag in the ultimate storm to pull the stern into a serious breaking wave....

The Jordan style drogue would be helpful to keep the boat from rolling while some repairs were made and is the best at keeping the boat in a stationary position if drift were undesirable. It also was the best at keeping the stern directly into the waves and at exerting a constant pull. Finally, I am confident that its design of multiple cones coupled with its deep riding nature would ensure that no matter what the wave situation it would never be caught in wave disturbance and lose any appreciable amount of drag. The disadvantage was that it rode too deep and exerted too much downward force on the stern of the boat. However, I will be putting a smaller weight on the end in an effort to reduce the downward pull.

Please note Gary's update after serveral mid-Atlantic gales