The views presented in this article are the result of observing
hurricanes over a period of 40 years in the Caribbean. I was on board yachts
for three hurricanes in 1954, one in 1960 and another in 1961.
Most experienced yachtsmen will agree with me that today, however, there is no such thing as a safe hurricane hole anywhere in the Eastern Caribbean. The holes are still there, but they are no longer safe because they are too crowded. The best prepared boat can be knocked adrift if another boat drags down on it.
The best way to prepare your boat for the hurricane season is to get out of the hurricane zone.
Before you object to what I state, I advise you to fax the US National Oceanic and Atmospheric Administration (NOAA) at (704) 271-4246 and order their book Tropical Cyclones of the North Atlantic (you can pay by credit card). This book shows the tracks of all the hurricanes and tropical storms recorded over more than a century. Study it, and then consider the increasing numbers of yachts based in and visiting the region.
Hurricane Tracks
With modern forecasting, many skippers think they can linger in the hurricane zone and then get away to safety when a hurricane is reported to be heading their way. But hurricanes are not always predictable creatures. ãWrong Wayä Lenny is still fresh in our minds, but there have been other hurricanes which have followed erratic and unusual courses. In November 1888, a hurricane hit St. Vincent, then turned north and hit every single island between there and Barbuda, before heading off northeast. In March (!) 1908, a hurricane started at 30°N and headed almost straight south, going over St. Martin, Antigua, St. Kitts and Nevis, before dissipating over the Caribbean. Many of us remember Hurricane Klaus, 5 - 13 November 1984, which started south of Puerto Rico and headed northeast over the Virgins.
Hurricanes can also follow each other. In 1916 three hurricanes ran right over the top of Tortola, St. Thomas, Culebra and northeast Puerto Rico. Grenada was hit by three hurricanes in 1887, and again in 1933. St. Vincent experienced three hurricanes in 1887, 1909 and 1933, and Martinique got hit three times in 1916.
Anchors, Rodes and Storm-Wind Loads
If you decide to stay in the hurricane zone (and donât intend to go to sea to weather a hurricane), youâll probably plan to stay at anchor in a so-called hurricane hole, ashore in a yard, or tied up in a marina. Whichever you choose, start making your preparations NOW ÷ not 2 or 3 days before a hurricane hits. Prepare your boat as well as you can, for your sake and othersâ.
AT ANCHOR
If planning to anchor, donât forget that wind pressure goes up with the square of velocity. If you are really inquisitive, collect a bunch of spring scales, attach them to your anchor rode and see the actual load on your anchor line at 20 knots of wind. At 40 knots, the load will be four times as great, at 80 knots 16 times as great, and at 120 knots 24 times as great.
An article which appeared in Cruising World magazine estimated the horizontal loading on an anchor line for a standard 40-foot cruising boat to be roughly 19,200 pounds in 120 knots of wind. Think of it this way: For a fairly light displacement cruising boat, the loading on the deck gear and anchor rodes is such that if you would expect them to hold in 120 knots of wind, you should also be able to attach the anchor lines onto a crane hook and physically lift the entire boat out of the water. How many boats have anchor rodes strong enough to take such a loading? (And how many boats have their windlasses, cleats and bitts attached firmly enough that they would not tear out?)
The Pardeys say in their book The Capable Cruiser that standard 3/8-inch Type Three anchor chain has a safe working load of 2,650 pounds and an ultimate breaking load of slightly over 10,000 pounds. Type Eight chain has a safe working load of 7,300 pounds and an ultimate breaking load of 29,200 pounds.
Three-strand nylon line has an approximate breaking strain as follows (different manufacturers give different figures):
1/2 inch 5,000 pounds
5/8 inch 8,000 pounds
3/4 inch 10,500 pounds
Added to the tremendous loading on an anchor line in high winds is the fact that in high winds boats do not tend to lie head to wind, but rather tack back and forth. As the wind catches them on the beam, the loadings skyrocket. As your boat veers, will your lines, bow-roller, cleats and fairleads stay in place under thousands of pounds of athwartship load?
Then, what about anchors? The anchor on the average 40-foot yacht (and on virtually all bareboats) is likely to be a 45-pound CQR, Bruce or Danforth. This ãheavyä anchor is backed up by a 35-pounder, with possibly a 25-pound stern hook. These anchors are dubious in the 60 to 80 knots of wind produced by a ãbrushä from a passing hurricane, and totally inadequate in 120 knots. To even hope to ride out a hurricane, you must use anchors so big they must be disassembled to stow ÷ such as the three-piece 150-pound Nevens-Herreshoff I carried on Iolaire.
When one looks at the loading that can be experienced in storm-force winds, it is obvious that no single anchor is going to hold. Numerous anchors will have to be put overside. (Iolaire weathered Hurricane Klaus in 1984 on the north side of St. Martin using six of our seven anchors.) But how should the anchors be placed? The old theory was that they should be placed in a star pattern, so that the boat could pivot around yet always be downwind of an anchor, lying head to wind, no matter which direction the wind was blowing.
In recent, more crowded years, this has proved to be a disaster, as no matter how good your star is, if a boat comes dragging down on you it will pick up part of your star and youâll both go whistling off to the lee side of the harbor.
As a result of that problem, many people now advocate putting two anchors on the same rode ÷ the heaviest at the end and the second secured 40 or 50 feet aft of the first, from which the line continues to the boat. This system has the advantage that, if someone drags toward you, you can (hopefully) steer off to one side and let them drag on by.
However, even two anchors on one rode wonât hold in over 80 knots. Thus, some would advise using four anchors ÷ two on each rode, with the rodes spread out in a Y. It is important that these lines be secured in such a way that their lengths can be adjusted. For example, if you are anchored in a Y and the wind backs, the port anchor line would begin to take all the load as the starboard line goes slack. It is then a case of taking in on starboard or veering more on port to produce equal loads on both lines.
The method of attaching your anchor rode to the boat requires considerable thought, as anchor windlasses and cleats under extreme loads are liable to come flying out of the deck. In many boats, you will discover that it is the sheet winches which are fastened more securely that anything else on the boat. Therefore, a good method is to attach two chain hooks to your anchor chain, with two nylon lines from the hooks back to your two sheet winches, as that will spread the load. (Rolling hitches can also be used to secure the lines to your anchor rode.) If taking nylon anchor rode itself directly back to a sheet winch, secure it with a tow-boat hitch (lightermanâs hitch), as the sheet cleats will undoubtedly be too small to accept the diameter of the rode.
Where your lines go through chocks, they will need chafing gear. There are all sorts of chafing gear toys on the market which may be fine for an afternoon at the marina, but they will not hold up in storm conditions. By far the best chafing gear is a length of heavy reinforced plastic hose of such diameter that you can slide it down over your anchor line in a close (but not tight) fit, so it stays in place. Four-foot lengths work well. These will absorb an awful lot of chafe, and if they do chafe though, veer just a little more line and a new piece of hose will be in the chock to take the chafe.
If you are riding out a hurricane in a mangrove cove, the advice of
most people who have actually done it is to stuff the boat right up into
the mangroves, with the anchors out astern and the bow tied right up into
the mangroves. Even if you get shoved up into the trees and suffer chafe
damage, it is doubtful you will suffer structural damage ÷ unless,
of course, some larger boat lands on top of you and squashes you flat as
a pancake.
Preparing Your Boat for a Hurricane
When preparing your boat for a hurricane, it goes without saying that windage should be reduced to an absolute minimum. Awnings, biminis, wind generators, inflatable dinghies ÷ put them all below. Booms can be removed and securely lashed flat along the side decks.
All sails should be removed and stowed below. Roller-furling headsails should be removed from the foils ÷ not only do they create windage but the chance of their unrolling is great. Numerous boats have ended up on the beach in a hurricane, often taking two or three other boats with them, because their headsails have unrolled. Winding the sheets around them wonât do. (Many of us feel that if your neighbor has not taken off his roller-furling sails, you are entitled to form a boarding party to go onboard, remove the roller-furling sails and stuff them below ÷ even against the neighborâs wishes.)
On boats with external halyards, all halyards should be run through ÷ EXCEPT the main halyard, so that you can go aloft and rethread the other halyards after the hurricane. On those boats that have internal halyards, all halyards (except, again, the main) should be disconnected from the deck and hauled through until the shackles are two-blocked at the masthead. The main halyard in either case should be set up tight, as close to the after face of the mast as possible. The windage of many oscillating halyards is infinitely greater than that of a single rigid one.
The question of dodgers comes up. Some advise removing them. Others, myself included, say they should be left in place if the boat is at anchor, so one of the crew could stay on deck and observe what is happening and be ready to place fenders, veer more anchor rode, etcetera. You can shelter behind a strong, well-anchored dodger if the boat is allowed to pivot head to wind. If the boat is ashore, take the dodger down.
While working on deck, one must certainly wear a safety harness, and crawl rather than try to walk. It is essential to wear facial protection, such as a diving mask and snorkel, to face into the wind and be able to see and even breathe. Some advise wearing a motorcycle crash helmet with full-face visor, others say ski goggles work fine.
IN A HOLE
If you have decided to store your boat ashore during hurricane season, the only safe way to do it is to remove the rig, dig a hole, and set the boat in the hole ÷ resting on overlapping tyres. Yes, tyres. Tyres work better than wooden chocks, but they must overlap. Install an automatic bilge pump, and leave it on. Even if you think your boat is watertight, rain driven by 120 knots of wind drives through all sorts of unknown cracks and crevices. There are stories of stored boats being opened after a hurricane with rainwater up to bunk level.
HAULED OUT
If you are unlucky enough to happen to be hauled out when a hurricane approaches, do everything to minimize windage, then double the number of supports. If the supports are wood, nail the wedges in place. If they are screw jacks, wire the handles through the screw jacks so they canât vibrate loose. Then have the yard weld re-bar to the screw jacks to encircle and tie them all together. If not on a concrete hard-stand, fit plywood pads to the legs of the supports. All too often with a hurricanes tremendous rains, the ground goes soft, the supports sink and the boat falls over.
Also, if hauled out, pull either a transducer or a speed gauge so there is a hole in the bottom of the boat to allow the rainwater that inevitably collects to drain out. (Donât do this if leaving the boat in a dug hole ÷ the hole may fill with rain, and the water then enter the boat via the hole.)
IN A MARINA
If you have decided to ride out the hurricane in marina, it is essential that the utmost care be taken regarding windage reduction, tying down everything that canât be stowed below, placing chafing gear ÷ and setting anchors in addition to the dock lines. Having seen a disastrous post-hurricane situation in Anse Marcel in St. Martin, which most of us had figured was an ideal hurricane hole, it is obvious that a surge CAN build up, a tremendous amount of chafe will occur, lifeline stanchions will get bent, toerails will get damaged and corners of transoms will get knocked off. Remove all lifelines and stanchions and, if possible, bow and stern pulpits. Not only are stanchions and pulpits expensive to repair or replace, but they often tear out at the bases, which will cost you even more money.
Start collecting old tyres NOW, not a couple of days before the hurricane.
To make fenders, drill two holes about one inch in diameter through the
tread face and thread a piece of 3/8-inch line down through the first hole
and up through the second, then AGAIN down through the first hole and up
through the second. (Now you have a bight that wonât chafe.) Secure
the ends with two half-hitches. When a hurricane approaches, line both
sides of the boat with tyres. Hang them from the toe rails, stanchion bases,
genoa tracks, chainplates, etcetera.
If the above preparations are taken, there is a chance that your boat
will survive, but luck will enter into it to a great degree.
After all preparations are made, pray.
This material has appeared in different form in previous issues of Compass.
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