Everyone dreams about the perfect trade-wind passage — 15 to 18 kts of wind, light puff- ball clouds overhead, long swells rolling up from astern, perfect sailing day after day, and little necessity to do anything more than make minor adjustments to sheets and halyards to minimize chafe by changing the nip.
This is sometimes how it is but, other times, a few squalls will blow through with a reasonable 25 to possibly 30 knots. At other times, the squalls are massive gear-busting blasts that may get up to 40 or more knots. Some years, the trades really honk and boats report a week or more of winds 25 to 30 knots and massive swells. At other times, they die out to 10 to 12 knots for weeks at a time; on her 1989 passage from the Cape Verdes to Antigua, Iolaire had her spinnaker up for 10 days. Other years, the wind dies completely as in 2005, when, on Sincerity, we powered for nine days.
For trade-wind sailing you must therefore be rigged for all eventualities.
The first and most essential piece of gear to put in place is a strong preventer on the main boom that be easily rigged and unrigged. The second thing to do is organize a way to sheet a headsail, via a block on a special bail, through the end of the main boom. (Photo available). Using the arrangement we developed on Iolaire almost 50 years ago, both the main boom preventer and the headsail sheet lead through the end of the main boom can set up at the same time.
You need a strong bail on the end of the main boom, preferably angled forward at about 45 degrees.
If you don’t have a suitable bail, you can use a loop of line to make a strop. Make the loop long enough that you can wrap it twice around the boom, tuck one end of the loop through the other, and work it tight. (The two wraps will ensure the strop doesn’t slip along the boom.) To make the loop, take a piece of line of the appropriate length, tie the ends together with a sheet bend, and mouse the tails of the knot with electrical tape. Secure a becket block to the bail (or to the strop). Secure a wire (or a length of high-tech line like Spectra or Dyneema) to the becket. This becomes the permanent part of the boom preventer. It should be about a foot shorter than the distance from the becket block to the gooseneck and have a thimble spliced into the gooseneck end of it. A lashing line tied into the thimble will allow you to snug the preventer up to the gooseneck and tight under the boom. (sketch available)
Lead two spinnaker-pole foreguys, one each side of the boat, through blocks at the stemhead or the end of the bowsprit. Clip the snap shackles to lifeline stanchions abreast of the mast and run the other ends aft to the cockpit.
To set up the preventer when you’re sailing, all you have to do is untie the line under the boom from the gooseneck and clip the snap shackle of the leeward foreguy into the thimble eye. Make the lashing line long enough that you can tie it loosely to the lifeline and use it as a retrieval line when it’s time for a jibe or when you no longer need the preventer because you are reaching.
Once the wind gets on the quarter and the boom is well eased, connect the preventer and set it up tight using a winch. If no winch is available, over ease the mainsheet, take up on the foreguy, then re-trim the main to make the foreguy tight. A jibe is now all but impossible. (Sketch available)
The becket block is there so you can permanently rig a reaching sheet with which to sheet a headsail via the end of the main boom. Lead the reaching sheet through the block and secure both ends to the gooseneck.
As soon as sheets are eased, one end of the reaching sheet can be attached to the headsail and the other end led through a block on deck fairly close to the main rigging and thence aft to a cockpit winch. Leading the headsail sheet this way opens the slot between the main and the leech of the headsail. It allows the headsail to draw better while minimizing its backwind effect on the mainsail, thus allowing the main boom to be eased more. (sketch available)
The correct downwind rig for trade-wind sailing is two headsails, one sheeted through the spinnaker pole and the other through the becket block at the end of the main boom as described above. To minimize rolling, the center of effort of the headsails should be low. This makes two fairly low-cut genoas preferable to a pair of high-cut jibs (sketch available). The flatter the headsails are sheeted, the less the boat will roll, so the number 2 genoa should be to windward and the number 1 to leeward.
If you have headsail roller reefing and the headfoil has two slots, hoist both sails on the headfoil. If the two headsails are of different luff lengths, add a pendant to the shorter sail to make the luff lengths the same. When stowed, one sail is rolled up on top of the other.
If it blows up in a squall, or if the trades are really honking and the two full genoas are too much, just ease the sheets slowly and roll up the sails one on top of the other until the desired amount of sail is still showing.
If the wind comes abeam, too far forward to fly the windward headsail, let the sail go to leeward and lie inside the leeward sail. To do this, come aback and, while leaving the pole in place, ease the windward sheet through the pole while taking up on the leeward sheet. You’ll be sailing with one headsail on top of the other, but this works just fine. In fact, this system works so well that it was outlawed under the IOR after Ted Turner figured out that if he hoisted a low-cut genoa inside a high-cut reacher he could gain extra sail area without increasing his rating.
If the wind comes so far aft that the leeward headsail is blanketed by the main, drop the main and sail under the two headsails alone.
If you do not have roller reefing headsails you can still rig a very good variation of the proper trade-wind rig with hanked on headsails.
Until 1987, when Iolaire was given Harken’s first big roller-furling/roller-reefing headsail gear to test, Iolaire was rigged with roller-furling headsails. That is, they furled on their own wire luffs and were either all in or all out. Only the working sails were on furlers; the light-air and heavy-weather sails were hanked on.
To set up the proper trade-wind rig, we installed a jackstay for setting a second downwind sail. We replaced the spinnaker halyard block with a becket block and attached a wire to the becket. The wire was 6 inches shorter than the distance from the becket to the deck and, when not in use as a jackstay, it was secured with a lashing line to a pad-eye alongside the upper shrouds.
To prepare for trade-wind sailing, we moved the jackstay to the bowsprit end and lashed it there. We hoisted the big hanked-on genoa on the headstay in the normal fashion and sheeted it to the end of the main boom, then hoisted the number 2 genoa on the jackstay and sheeted it through the end of the spinnaker pole as described above.
This rig worked fine for Iolaire on her 1975, and ’85 passages and for Lone Star on her 1984 passage.
As noted in Chapter 00 of this guide, all those passages were fast. Hanked on headsails can present a couple of problems when sailing downwind. As the boat rolls back and forth, piston hanks, especially if they are old, tend to open up with the result that, after a while, you may find that the headsail is secured at the tack and head and nowhere else.
Also, it has been known for a piston hank to open and then lock closed over the other stay. If this happens, it is impossible to drop either sail. Both have to be dropped or partially dropped to clear the foul.
To prevent the piston hanks on one stay from snapping over the other stay, set the hanks in opposite directions: On the headsail hoisted on the headstay, face the hanks to port; on the headsail on the jackstay face them to starboard. The hamks then cannot hook the two stays together.
Toplicht hanks open in the vertical plane. By fitting them to your sails you will eliminate the problem of hanks either inadvertently opening or hooking onto another stay or loose sheet. (photo).
We didn’t install roller-furling/roller-reefing gear on Iolaire until Olaf Harken gave us the first big gear the Harken brothers made. He asked me to test it to see if it was indestructible. We tested it. That winter was a windy one and I put the bricks to it. It was indestructible!
The reason we did not install this kind of gear earlier was that broken and bent-up roller- reefing/roller furling gear was stacked up like cordwood in rigging lofts up and down the Eastern Caribbean.
Ketches and yawls come into their own downwind as they can set a mizzen staysail, which will not blanket the lee headsail whereas the mainsail will. A proper mizzen staysail that tacks down alongside the main rigging is a really useful sail. On a yawl it will be two thirds the size of the main and on a ketch it will be at least as large as the main.
When handled properly, a mizzen staysail is easy to set and douse. The sheet should be really long and have a stopper knot a foot forward of the bitter end. When preparing to set the mizzen staysail, attach the sheet to the clew but leave it slack while you hoist the sail. Take in on the sheet only after the halyard is two-blocked and secured.
When the time comes to douse the mizzen staysail, make sure the bitter end of the halyard is secured then blow the halyard but hold the sheet. The sail will rag off to leeward where it’s easily muzzled. Once it’s muzzled, you can ease the sheet.
This system works fine on boats to about 70 feet. On larger vessels, a temporary stay makes a difference in setting and dousing the sail. This stay can be a length of light 7 x 19 wire or Dynema secured to the mizzen masthead and long enough to reach the deck at the main rigging, where it can be secured with a light lashing line. The mizzen staysail should have a few jib hanks attached to the luff. Before hoisting the mizzen staysail, hank it to the temporary stay. You can then hoist and douse the sail as described above. Since it’s secured to a temporary stay, one crew member can haul down on the luff once the halyard is blown.
When not in use, the stay can be stowed coiled on the mizzen mast around easily made fittings. (Sketch available.)
The late Wing Commander Bob Carson RAF (ret.) installed this system on my recommendation on the 95-foot yawl, Gitana IV. He said it worked to perfection: Two crew could set or douse the mizzen staysail with no trouble.
A spinnaker pole 20 percent longer than the base of the fore triangle will allow you to set a 135-percent headsail really flat, minimizing the roll. This is where a telescoping pole earns its keep. Many companies make them but Forespar seems to have the best reputation. Whatever size the pole manufacturer recommends for your fore-triangle length, go one size larger. It’s worth the expense as you shouldn’t have to worry about an oversized pole bending and jamming.
If you can afford it, a carbon-fiber spinnaker pole is a very worthwhile investment. On a fore triangle of 18 feet with a hoist of 50 feet, a wooden pole will weigh about 45 pounds, an aluminum pole 35 pounds, and a carbon pole 18 pounds or less.
If you only have one headsail on your boat, you’ll need to buy a second one. Remember you are cruising, not racing. Go to a company that specializes in secondhand sails (not too many companies in Europe do this but plenty in the States do) and purchase one of the approximate size that you want. Take it to a sailmaker and have him re-stitch the leech and the foot and 3 feet in from the leech on all the seams.You are using this sail downwind so a secondhand sail will do the job.
While we dream of consistent trade winds, all too often they are not, so carry a spinnaker or possibly two. Again, you are cruising, not racing. Leave the racing spinnaker in the sail locker. Buy one or two secondhand spinnakers.
If the wind goes light, set the spinnaker, but make an absolute rule that the spinnaker must be doused before any squall catches up with you. Make another rule that the spinnaker must be doused and the rig switched to the two headsails as soon as the boat’s speed reaches the square root of the boat’s waterline length plus 15 percent. Also, set the spinnaker with a light sheet, say about 3/8-inch three strand Dacron. When it starts to blow, the sheet will tend to unlay and become smaller, something even the dimmest on- deck crew will observe. If properly instructed, he will then call the skipper who can insist the spinnaker comes down before it blows.
A snuffer is essential gear when cruising with a spinnaker. When buying a snuffer, go one size larger than whatever size nose cone the sailmaker recommends. This will make it much easier to snuff the spinnaker. Snuffers do work as long as they are handled correctly. Before you try to snuff the sail, the boat must be headed dead downwind. You don’t need to worry about jibing as you have a really good main boom preventer rigged.
Ease the pole all the way forward so the spinnaker collapses behind the main and then pull down on the snuffer.
If the snuffer line is rigged directly to the nose cone, a crew member can only pull down his or her own weight. If the resistance is greater than that they will lift themselves off the deck. Two crew pulling down just get in each other’s way. Lead the down line through a snatch block set at the forward end of the foretriangle, then one, two, or even more crew can heave on it and the snuffer will snuff. The foredeck crew on the J-Class yacht, Shamrock V, was having trouble with the snuffer until I suggested the haul-down line be led through a snatch block. Then five crew members tailed on the down line — and that was the end of the snuffer problem.
Asymmetric spinnakers are great. When using these sails, it’s worthwhile installing a removable stub bowsprit (sketch can be provided) as it allows you to sail deeper than when the sail is tacked down at the forward end of the fore triangle and makes jibing the sail much easier. However, for the heavy- or moderate-displacement cruising boat, it’s essential to carry a spinnaker pole in case the wind goes dead aft.
When sailing dead downwind, the apparent wind is dead aft. As soon as you head up to a reach, the apparent wind begins to move forward. The faster you sail, the futher forward the apparent wind goes and the faster you sail — up to a point.
Boats that sail really fast, either because they are very light or long or both, can sail 90- degree jibe angles and make money. For them — light displacement flyers or fairly light megayachts, tacking downwind with an asymmetric is a race winner, but a heavy- displacement cruising boat does not sail at a sufficiently greater speed when reaching to justify sailing at jibe angles of more than 20 degrees, as the table shows. [do you mean 20 degrees total or 20 degrees each side, i.e. jibing thru 40 degrees? at 20 total you only need to sail 1.5% faster] 20 degrees total only 10 degrees off base course well worth while but further than that check speed increase against the table and sail accordingly. Jeremy I am no good on working VMG off a hand held but I am told it can be done. So put in your destination and hand held gps or built in nav instrument will tell you which course is the fastest I leave this to you say the author not competent but the editor etcThis was illustrated on Sincerity’s 2005 transatlantic. She is an 88-foot ketch and sails very well but we had no pole, only a big asymmetric. To keep it full we had to sail 90 degree jibe angles. We were doing 9 to 10 knots through the water but only 6 to 7 knots on the course to Antigua.
The winner of the 2009 ARC was a Vovo 60 that set an asymmetric, sailed the angles, and completed the race in 11 days and 18 hours. Her sailing distance was 3,600 miles, which means she averaged 306 miles per day at an average speed of 12.75 knots [at 42 degrees off the true wind, i.e. jibing through 84 degrees]. Had she sailed a direct great- circle course, her sailing distance would have been about 2680 miles. To do this distance in the same time, she would have had to average only 228 miles per day, or an average speed of 9.5 knots. Given her size, this would seem to have been easily achievable and would have required a lot less jibing. [I’ll go dig up the time for the Wally in case that’s the boat you’re talking about.]The Wally and the open 60 finished within minutes of each other but your point that the wally probably had no spinnaker pole she had to sail the angles but because of her size and light displacement she could pull the wind forward but a heavy displacement boat can not.
In the light of this one can see that, even if you are carrying an asymmetric, you should also carry a spinnaker pole so you can sail dead downwind if you need to.
You are rigging the boat to sail the trade winds. Those trade winds will blow you to tropical islands with crystal clear water and harbors that are surrounded by coral reefs that will in 10 yards will suddenly change the water depth from 30 or more feet to two feet.
Much more important than your GPS, chartplotter or fathometer is the old-fashioned, good-old Eyeball Mark I navigational instrument that god, not an electronic specialist, gave you. When entering harbors or threading your way around reef-encumbered islands, a bow lookout is essential. He (or she) will be even more useful if standing on the bow pulpit. [want to add mast steps in here?]yes
You are rigged correctly, all is well, and you are enjoying a downwind passage. You will be needing electricity.
Why listen to the noise , and smell the exhaust fumes when via a taffrail generator that will put out at 6 kts 144 amps at 12 vots a day, or a shaft generator that will put out 40/60 amps at 12 volts at six knots?
The July 2008 issue of Yachting World reported the results of a survey of ARC boats. Boats that used their generators to produce electricity ran their generators an average of 4.9 hours per day, while those that used their engines ran them 3.2 hours per day on average. This unnecessary running of engines or generators to produce electricity not only introduces carbon dioxide and other nasty things into the global environment but, since you are going downwind, those exhaust fumes are coming aboard and blowing the length of the boat. Also, the noise of the engine is disturbing the blessed silence you enjoy when under sail.
Go to taffrail and shaft generators here, then follow on with this. There are other ways to produce electricity.
Wind generators are almost useless on trade-wind passages as, when sailing dead downwind or almost so, the apparent wind across the boat is not sufficient to produce useful amounts of electricity. Wind generators produce a useful amount of electricity when under sail in the Eastern Caribbean because, most of the time, the wind is abeam or forward of abeam. At anchor, whether of not the wind generator will produce useful amounts of electricity depends on the anchorage. In an exposed anchorage like the Tobago Cays or similar, or anchored on the windward side of small island like Carriacou, Mayreau, or Canouan, where there wind will not die out at night, the wind generator may produce all the electricity needed. However, when anchored in harbors on large islands where the wind dies out at night, the generator or main engine will have to be run to augment the amount produced by the wind generator.
So, before taking off on your trade-wind passage, install a wind generator, as it will earn its keep once you reach the Caribbean.
The higher above the water, the greater is the wind velocity. To give the greatest benefit, a wind generator should be mounted high off the deck. On a ketch or a yawl, it should be on the top of the mizzen mast. Not only will it work at its best there but it won’t interfere with the flying of a mizzen staysail.
Solar panels are great on multihulls but monohulls don’t have the deck area to spread out enough solar panels to produce really useful amounts of electricity.
So, you’re sailing downwind in the trades, your wind generator isn’t doing much and you don’t have enough solar power to make up the deficit. You can still generate all you need without turning on the engine if you install a taffrail water-driven generator.
The Ampair 100 taffrail generator (which Ampair developed from an application I invented and first installed on Iolaire in 1979) will produce 6 amps at 12 volts when sailing at 6 knots. That’s 144 amp hours per day. At 7 knots it will generate 156 amp hours per day and the drag, as measured with a spring scale, is only 15 pounds. As soon as you are under way, you toss over the stern a 12-inch diameter propeller on a 3-foot rod attached to 60 feet of ½-inch braided line and let her run.
To easily retrieve the propeller, you need a 14-inch plastic funnel split so you can slip it over the towline. It will slide down the line and muzzle the propeller so it stops spinning. The propeller and towline can then be hauled back aboard without the line becoming twisted. (This rig was invented in 1985 by Lou Lou Magras of Gustavia, St. Barts, who was also one of the founders of the St. Barts Bucket.)
At speeds higher than correction here 8 knots, the propeller might jump or skip, so Ampair has developed a special propeller for bigger boats that might sail consistently at 8 knots or more. You can also lengthen the towline or add weight to it, both of which will help keep the prop in the water.
Wiring the Ampair is a simple matter of running two wires from the generator (which is slung from the stern pulpit) directly to the battery. If there’s a chance of overcharging the batteries, just run the refrigerator longer than usual or turn on some lights.
The engineless Iolaire on here last five transatlantic passages has had cold beer all the way electricity provide by Ampair taffrail generator and wind generator mounted on the TOP of the missen mast(I have photo of the wind generator with white eagle pointed on the vane. Iolaire is a proper yacht flying flags the proper way yacht club ensign on the main mast private signal on missen mast.
Output of the Ampair 100 flattens out at about 6 amps. If 144/156 ampere hours a day is insufficient for your needs or if you consistently cruise in trade wind conditions at a speed of 8 or 9 knots, you have a couple of options. You can install an Aerogen or a generator driven by your propeller shaft.
At sailing speeds above 6 knots the Aerogen’s generating rate continues to climb. However, because the Aerogen requires a special mounting bracket on the stern, it’s an expensive installation. One ARC boat reported the Aerogen was a good installation but the total cost including special brackets and wiring set him back £5,000, whereas the Ampair generator just hangs from a sling on the stern pulpit and costs £600.
It’s manufacturer claims the Aerogen is a dual-purpose weapon — a water generator at sea and a wind generator in port. Forget about the wind generating aspect of the Aerogen as the unit is too low to really pick up the wind plus the windmill is only about 3 feet above the deck, which makes it an accident looking for someplace to happen.
For a lot less than the cost of an Aerogen, you can install a shaft-driven Electrodyne alternator that will produce more electricity than even the most electrically hungry boat can use.
Shaft generators have been around for 60 years. The 40-foot Block Island ketch, Lang Syne, sailed around the world in 1948/49 with refrigeration and an electric autopilot, both of which used vast quantities of electricity. All the electricity used aboard was produced by a shaft generator.
Steve and Linda Dashew sailed around the world in the early 1970s on Intermezzo, a 55- foot aluminum cutter on which all electricity was produced by an Electrodyne low-rpm alternator driven by a 12-inch propeller.
Correctly geared, an Electrodyne low-rpm alternator driven by an 18-inch propeller will produce between 40 to 60 amps at 12 volts at 6 kts. (lets hedge our betts here as I worked out 60 amps on the speed Iolaire prop was turning at 6 kts, but of course once the alternator kicks in how much will the shaft slow????? Hence hedge betts, but also some boats will have biggrer props , the bigger the prop the more torque the less the alternator will slow the prop down. This is more than enough electricity for even the most power-hungry boats at a cost of $600 for the alternator plus installation. Allowing the prop to freewheel three or four hours would generate sufficient electricity for a day, after which the propeller shaft can be locked to minimize drag.
The ideal installation would be built around a controllable-pitch propeller. The pitch of the propeller could be adjusted to generate the desired amount of electricity when needed and at other times the propeller could be feathered to minimize drag. A controllable-pitch propeller is also more efficient for powering a boat as the pitch can be adjusted to suit the boat’s speed and the sea conditions.
Why run noisy, smelly generators when you can generate electricity silently and withou creating pollution?
Aerogen: LVM Ltd. (a division of ITT): www.lvm-ltd.com (Electrodyne, Scarborough ME, 207 883 4121 www.electrodyne.com brushless alternators)