Bow or stern which

scheme is better?

So far we've gone through five different storm management schemes for fore-and-aft-rigged monohull sailing boats 25 to 55 feet in length. I've attempted to cover all the arguments for and against each technique.

To sum up, I propose the following actions:

1. Deep reefs in the mainsail; a smaller headsail.

2. Heave-to by adjusting the sails.

3. Lie a-hull. No sails up in regular seas.

4. Run off, perhaps with a tiny storm jib at the bow.

5. Employ a parachute sea anchor from the bow or a drogue device from the stern.

My suggestion is to use these storm moves in order—from 1 through 5. The first four are traditional plans for coping with wind and seas, and mariners have used these techniques for hundreds, perhaps thousands, of years. None of these four cost anything, and they'll get you through most bad weather. They require no special equipment and are quite adequate for ordinary storms. At least they've served me and my sailing friends well.

Number 5—parachutes and drogues—is made up of more modern ideas designed to deal with breaking waves and horrific storm conditions. These off-the-boat devices use the concept of a line coming from a strong point away from the yacht to keep the bow or the stern pointing into the wind and waves. Hopefully these inventions can help us stay away from those terrible words: Lost at sea.

Plan 5 requires special equipment and perhaps minor modifications to the boat. In addition, the handling and recovery of these devices may be difficult— sometimes extremely difficult. You will need some hauling strength, which means tackles, winches, or a windlass. Since most recreational sailors will never see storms of Force 9 or above, except from the safety of a marina or protected harbor, each captain will have to decide whether to burden his or her yacht with still another piece of equipment.

If you choose your seasons carefully and do your best to stay away from bad weather, there's a good chance that you will never experience a strong gale, a storm-force problem, or see a 30-foot breaking wave. But who can tell?

Reports from many sources agree that easing something over the transom and letting out a line is much simpler than dealing with a parachute, float, shroud lines, and a cumbersome nylon warp that can be as much as 500 feet long. It's easier to check a stern line or a stern bridle for chafe from a rear cockpit than from the foredeck, where even the brave may fear to tread in a violent storm. The rudder is safer with a drogue, although a weak cockpit structure can be a danger.

One user of both parachute sea anchors from the bow and the Jordan Series drogue from the stern is the veteran English sailor Noel Dilly, who campaigns a 28-foot Holman & Pye Twister design named Bits. Professor Dilly says that the series drogue has no give at all, "whereas with the para-anchor, it is like attaching the boat to a bungee cord that is being loaded and unloaded all the time."

He adds: "The series drogue acts faster than any other device, and it will align the stern to the wave direction soonest after a wave strike."62

In recent years the Wolfson Unit of the School of Engineering Sciences at the University of Southampton in England, supported by funds from the Royal Ocean Racing Club, has studied storm tactics. Among many projects, the scientists have investigated the influence of drogues or sea anchors on a yacht's behavior in breaking waves.

"This research . . . complemented similar studies in the USA by Donald Jordan," writes Peter Bruce, the editor of the 30th anniversary edition of Adlard Coles' Heavy Weather Sailing. "These studies showed that use of a suitable drogue, deployed from the stern of the yacht, will cause it to lie steadily downwind and downwave. This means that any breaking wave will see only the transom of the yacht and will not be able to exert any capsizing force."63

If you're going offshore in less than perfect weather or have doubts about what you might find, I recommend that you carry either a parachute sea anchor or a drogue or, in an ideal world, both. Parachute sea anchors certainly have their place in storm management situations, and over the years have saved hundreds of yachts. A drogue is far simpler to use, however, and has the advantage of keeping a steady track (less yawing).

I opt for one of the following:

1. The Jordan Series drogue is the best of the lot in my judgment and has been carefully engineered for the ultimate storm. The trouble with a long elastic rode and a single-element drogue or parachute at the far end of the line is that the load may not build up fast enough to catch the boat in time to hold her bow or stern into a breaking wave. With its multiple cones, however, the Jordan device jumps to its maximum drag strength in a few seconds and will hold the boat's stern into a breaking sea. Other schemes may not act quickly enough.

Series drogues can be bought completed or in kit form from several sources. One is Ace Sailmakers, of East Lyme, Connecticut (see Appendix 1 for address).

2. The Galerider drogue was designed by Skip Raymond and is sold by Hathaway, Reiser, and Raymond sailmakers of Stamford, Connecticut (see Appendix 1 for address). I've already discussed this drogue, which has been bought by thousands of sailors since its introduction in 1984.

The Galerider is simple to use, uncomplicated, and can certainly help a yacht in difficult circumstances. Nevertheless, it is essentially a surface instrument. I have seen photographs of a Galerider drogue just at the surface (or a few inches below) kicking up a tremendous fuss and significantly slowing the boat. However, there is no design mechanism to sink the drogue in case of an accelerated breaking wave. (Would a chunk of lead or a short length of chain help to sink the drogue slightly?) In a large breaking wave during the ultimate storm—which may never be met—I fear that the Galerider might skip down the front of a big overtaking wave and fail to hold the stern of the yacht into the wave. Nevertheless, this device is an excellent product because of its modest cost, simplicity, ease of use, and compact stowage. Certainly the Galerider is easy to understand and is a hundred times better than towing automobile tires.

3. The Seabrake drogue, invented and patented by John Abernathy of Merimbula, Australia, has been sold in various models since 1983 (see Appendix 1 for address).

Normally the front of the Seabrake should be weighted with 2 meters of 3/8-inch chain, shackled between the drogue and a 50-meter braided polyester line (not nylon), say the instructions. The Seabrake is designed to travel just below the surface of the water at from 3 to 7 knots.

This large drogue is made of two cones of stout blue fabric that are positioned so that the larger diameters ofthe two cones face each other (separated by a short space). Rings ofheavy stainless steel wire support the cones, which are held together with wide nylon strapping. At low speeds the flow through the two facing cones is moderate, but at higher speeds the flow increases sharply and tends to inflate the aftermost cone. This partially closes the rear exit for the water. Now instead ofleav-ing through the aft part ofthe rear cone, most ofthe water pours out ofthe space between the two cones and greatly increases the drag ofthe device.

This large drogue is made of two cones of stout blue fabric that are positioned so that the larger diameters ofthe two cones face each other (separated by a short space). Rings ofheavy stainless steel wire support the cones, which are held together with wide nylon strapping. At low speeds the flow through the two facing cones is moderate, but at higher speeds the flow increases sharply and tends to inflate the aftermost cone. This partially closes the rear exit for the water. Now instead ofleav-ing through the aft part ofthe rear cone, most ofthe water pours out ofthe space between the two cones and greatly increases the drag ofthe device.

The water flow pattern ofthe Seabrake as drawn by the inventor.

This Australian device is quite large and comes in various sizes, depending on the length and weight of the boat. If this drogue is towed from a bridle and the lines are taken to port and starboard cockpit winches, a vessel can be steered by taking up or letting out the bridle lines. It can also be used as a bosun's chair, as a vertical flopper stopper to minimize rolling at anchor, and as a control device when entering rivers or inlets or crossing a bar when coming in from the sea. The units do not rotate and don't need a swivel at the front of the drogue. The Seabrake has been used successfully by many sailors, particularly in Australia.

4. The Seaclaw drogue is made and sold by W. A. (Bill) Coppins of Motueka, New Zealand (see Appendix 1 for address). This device is constructed of strong ripstop PVC and is designed as a large squarish bag with stainless steel spreaders. In use the bag is pulled along by two straps sewn along the top. The harder the pull, the more the Seaclaw tends to dive, so that in a breaking wave situation, the drogue is pulled deeper instead of being snatched out of the water. Normally the Seaclaw works at a 6:1 dive ratio, which means that with the recommended 60 meters (about 200 feet) of line out, the drogue runs along at a depth of 10 meters.

Towing Vessel Bridle
The carefully engineered Seaclaw drogue is essentially a squarish bag that is dragged behind the vessel to slow her. The greater the pull, the more the drogue tends to dive.

According to its maker, no weight (chain) is needed to sink the device because its shape keeps it below the surface of the water. With increased forward pull on the drogue, the Seaclaw has a reverse thrust arrangement that creates additional drag. The Seaclaw also has a small built-in float that lifts the drogue to the surface when the pull on the device is stopped after a storm.

5. The Delta drogue was invented and patented by Don Whilldin of Silt, Colorado, in 1994 (see Appendix 1 for address).

The Delta drogue is made of vinyl-coated nylon fabric and is available in five sizes, depending on the length of the vessel. "Sizes are baseline only," says Whilldin. "If you prefer more drag to go slower, go to a size larger. If you prefer to go faster (less drag) go to a size smaller."

The line connecting the Delta drogue to the vessel should be a minimum of 200 feet long, says the maker, and is designed to be shackled to a bridle with legs at least 50 feet long to allow for adjustment. A short length of chain at the drogue end will help keep the device below the surface. When the drogue is in the water behind the yacht, "try to position the device so that it's in the meaty part of the

Drogue Vessel
The speed-limiting Delta drogue is made ofheavy-duty material. It should be weighted and towed behind the vessel on a line at least 200feet long.

wave and not in thin air," says Whilldin. "This is important because drogues have been known to pull out of wave faces. When this happens, the towline goes slack, the boat takes off on a sprint, and may yaw, broach, or capsize. When the drogue finally takes hold again, it may wrench something out of the deck or cause [other damage]."

Whilldin lists four uses for drogues:

1. Speed-limiting drogues can be of immense value in strong following seas and have been used to stabilize the attitude of small craft since antiquity. No doubt there are many yachts sailing today that would have gone down had it not been for the grace of God and some sort of drag device that slowed them down.

2. Towed off the stern with a bridle, a speed-limiting drogue can be used as an emergency steering device in the event of steering failure by adjusting the lengths of the bridle legs to generate yaw.

3. Towed off the windward quarter, a speed-limiting drogue can be used to help maintain directional stability while negotiating dangerous harbor entrances.

4. Towed off the stern of a vessel in tow, a drogue can all but eliminate the dangerous "whiplash" effect when the towing boat slows or stops.

According to Whilldin, a speed-limiting drogue will significantly increase the efficiency of an autopilot. If the drogue is used with a bridle, most boats will steer themselves. If a drogue is used without a bridle (and with the towline secured well forward of the rudder) the boat can be steered through an arc of 90 degrees to avoid ships, reefs, headlands—any and all problems that are ahead.

The last of the drogues (#6) is the Para-Drogue (see drawing next page) invented by Alby McCracken of Sale, Australia (see Appendix 1 for address), and consists of two small towed parachutes, one behind the other. The forward (and larger) parachute is attached to the end of an 80-meter (about 260 feet) line connected to a bridle on the boat. The shroud lines of a much smaller parachute are fastened to the dome area of the larger chute. Each of the parachutes is cut differently, and they interact with each other, "creating a very high drag and consequent pressure wave," says McCracken.

The Para-Drogue will not break free of the water and maintains an even and positive drag on the stern of a vessel, according to the maker. In tests, the device showed a drag of 265 kg at 5 knots, a drag of 480 kg at 7 knots, and 890 kg at 9 knots. Unlike other drogues, the bridle ends are shown fastened to the midships area and well forward of the ship's rudder. This means the boat can be steered to a limited extent.

On a recent test aboard a yacht sailing to Antarctica and overtaken by gale-force winds, this steering arrangement worked well and allowed the crew to steer by winching in the bridle line on the side they wanted to turn. Under some circumstances a spinnaker pole can be strapped athwartships across the transom and the bridle lines run through blocks at each end of the pole and back to the cockpit sheet winches. This allows easy emergency steering by adjusting the bridle lines on the winches.

drogue

As might be expected, when Alby McCracken invented his Para-Drogue device he employed a small parachute astern plus a still smaller chute aft of the principal one. Alby recommends that his bridle lines go to a midship position.

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In the previous fourteen chapters I've written all I know and have been able to find out about controlling a sailing yacht in upset seas and windy weather. Here now are some thoughts on a few related aspects of the offshore sailing game:

Chapter 15. Passage Planning: The Best Time to Go Chapter 16. The Chart Game, or Where Am I? Chapter 17. Is a Storm Coming? Chapter 18. A Hurricane: The Evil Eye Chapter 19. Fear and Uncertainty

There is also a glossary with hundreds of sailing terms. Some of these words are vital; others are important. A few may be obscure. But all are necessary so that sailors can talk to one another in precise terms quickly and without confusion.

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