For information on Dutchman and uncontrolled jibes, click here.

Single Line Reefing

Sails are under a very large strain when delivering power to a boat in high winds.  Our two engines deliver about 50 horse power to move us at between 5 and 6 knows.  Sails, even in a moderate wind, can exceed or often double this speed.  The power required to move a boat increases much faster than the speed.  I guesstimate our sails deliver over 100 horse poser in a 25 knot moderate breeze.

The Shearwater was delivered with one powerful electric Anderson winch and three manual winches.  The electric winch is installed where it can be used to raise the 250 pound main sail and trim the port jib sheet.  This winch produces significantly more "pull" than its identical system winch on the starboard side.  Ideally, all the heavy tasks would be performed by the electric winch - reserving my limited strengths for bottle opening and picture taking.

We prefer to stay in the cockpit during heavy weather and very high winds.  One of the most serious boating dangers we face in heavy weather is falling overboard.  An overboard sailor in heavy weather at night is almost never recovered - not even the body is found.

The rigging on a cruising boat should be set up to permit the sailors to remain in the cockpit almost all the time.  It is essential to remain in the cockpit for maximum safety in very heavy weather, sudden squalls, or strong winds.

Unfortunately, Voyage did not deliver the Shearwater with the necessary rigging to permit reducing the mainsail from the cockpit.  The rigging, called reefing lines, was not ideal for our intended use so we decided to rebuild it prior to leaving Cape Town.

The first try worked OK,  the second worked better when installed in Trinidad.  Finally, in Florida we got it right.  We can now reduce the main sail in increments using the power of the electric winch without leaving the cockpit.

Most main sails are provided with two or more sets of reinforced holes called cringles.  These cringles are matching sets of holes in the front (luff) and rear (leach) that pull the sail down in even slabs.  Lines are attached to pull the sail down in increments and reduce the size as necessary.  The Shearwater has three sets of cringles numbered 1, 2, and 3 from the bottom up.

The first, the number one cringle reduces the sail area about 20% and was found to be such a small reduction that we decided not to use it.  The second and third (number 2 and number 3 reef points) are rigged on the Shearwater.

The sheet stops - or line breaks - originally installed by Voyage were also insufficient in number for reefing as we intended it to work.  We required two reef line(s) and the main halyard be lead to the same winch.  This is necessary so one person can adjust the main sail and associated reef line(s) at the same time.  Voyage eventually agreed they had specified two reef lines in their brochure bound as part of our contract.  They installed a sheet stop on the port side, moving the boom derrick line to the new sheet stop and conveniently providing three stops in a row for the main halyard, number 2 and 3 reef lines.  In the photo on the left, the teal line with two markers is the boom derrick.  The left white line with green trace is the main halyard.  The white/red and white/green are the number 2 and 3 reef lines.  Note, they travel forward through the Lexan windshield we installed as part of the bimini upgrade.

The photo below is the port deck organizer (also called a collector).  After the rigging changes, the left most line continues to pull our boom derrick to enable lifting of our tender.  The second line is the main halyard used to pull up the main sail.  The third and fourth lines are the number 2 and number 3 reefing.  These lines pull the luff and leach of their respective reef points down and create a "neat" slab of sail that is stored automatically in the sail cover.

The pulleys in the deck organizer provided by Voyage were a hard plastic and insufficient for the loads placed on them by the main halyard and reefing lines.  We broke several of the hard plastic pulleys.  With help from Spinlock, we replaced all the pulleys in both organizers with alloy pulleys that has withstood the load without damage.

The luff blocks (number 2 shown on the left) must  not be a swivel block.  If you use swivel blocks on the luff and leach, the line will tangle terribly, making it impossible to reef.

The luff block turns the line and it goes back down to the mast base where you see it in the photo on the left.  This block reduces the friction normally associated with running the reefing line through the cringle.  The second mast base block turns the line again so it goes up where it enters the boom, just like it used to before we made the changes.  Once it exits the aft end of the boom the line goes to another block shackled to the number 2 leach cringle where it turns again and goes down to be tied to the boom.

The leach block is needed only on the number 2 reef point since the sail must be very tight to hold its design shape in heavy winds.  We omitted the leach block for the number 3 point, fastening the number 3 reef line directly to the number 3 leach cringle.  This was sufficient to obtain the shape we wanted in the higher winds requiring three reefs.

The same technique is used on both side.  The green reef line exits the deck organizer, turns, goes up to the number 3 luff reef block on the mainsail, turns again and goes back to the mast base where it turns one more time.  Now the line goes up to the boom, turns again and goes aft to pull the leach down as needed.

This all seems much more complicated than it is in practice.  To reef, all we do is wrap the main halyard around the winch, take some tension and release the main halyard sheet stop.  We allow about two feet of line to go out and re-stop the halyard.

Now we wrap the number 2 reef line around the winch and pull until there is a bit on tension on the reef line.  The Shearwater is now 0.2 reefed.  We repeat this process several more times until a mark we applied to the main halyard indicates that sufficient line has been played out to lower the mainsail to the number 2 reef point.

We grind in the reef line on the power winch until the corresponding number 2 reef line is visible.  Normally we do not have to play out any mainsheet since the winch and rigging are strong enough to shape the mainsail under load.  We have done this in up to about 45 knot winds with no problems.  Normally, we reef much earlier, 25 knots or so, depending on other wind and sea conditions.  At 25 knots there is no apparent strain on the winch.

Uncontrolled Jibes

Uncontrolled Jibes - the rapid swinging of the boom as the wind switches from one side to the other when traveling down wind - is a frightening and dangerous aspect of sailing in a large boat.  The forces are sufficient to break hardware and if you are unfortunate enough to get hit in the head by a boom on a Jibing sailboat, you may be knocked overboard or suffer severe injury.

The Shearwater, as delivered, has a very long traveler so the effects of an unexpected jibe can be moderated if you move the main sheet car to the downwind side of the traveler and reduce the main sheet.  This will reduce the time the boom has to build up speed - and energy - in an unexpected jibe caused by a sudden wave or wind shift.  This is especially important when sailing at night since everything seems louder, faster, and harder to sort out on the midnight to 4 am watch.

The usual way to prevent uncontrolled jibes is to attach a line to the aft end of the boom and secure it to a strong point on the down wind side.  This line, a preventer, solves the problem but creates a new one.  When a wind shift requires a jibe, you must remove the preventer, jibe, and reconnect the preventer.  On the Shearwater this requires two trips out of the cockpit - an action we take with safety harnesses and two people on deck.

We looked for a way to reduce the "crash" on the jibe and eliminate the manual intervention necessary to set the preventer on the new down wind side.

Dutchman to the rescue.

The device in the photo on the right is a Dutchman - generally found attached to the mid-boom of monohulls.  The white line/blue trace line is attached to the two aft cleats and is slack when the boom is mid-ships.  The natural geometry of the boom travel tightens the line as the boom approaches the point where the main sail will chafe on the shrouds - effectively providing a stop point.  The Dutchman (we use a 7/16" unit) has a friction adjustment on the bottom pulley.

The combination of line geometry, line tension, and friction adjustment takes a few tries to get right.  Once it is right, we center the traveler, adjust the main sheet to permit the sail to just "kiss" the shrouds and travel down wind.

In the event of a jibe - either intentional or accidental/uncontrolled, the friction of the line in the Dutchman dissipates the boom energy, slowing it down before the main halyard brings the boom to a stop on the new lee side.  There is some "crash" - but it is quite tiny compared to the non-Dutchman jibe.

When there are just two of us on board, the Dutchman is as much a part of the crew as the autopilot.  With a larger crew or when trying to get the very best out of the boat, we reduce the tension on the white/blue trace line and the Dutchman no longer has any noticeable effect.

The three white/red trace wraps are a temporary attachment point for the Dutchman.  We will replace them with a proper bale or weldment when we find one.  We recommend you resist attaching the Dutchman to the mid-boom point as recommended by the manufacturer.  Part of what must be accomplished is to dissipate the larger energy of the very large main sail normally carried by a big cat.  A mid-boom attachment will place much larger loads on the boom (we had a monohull friend split his in to two boomlets), the line, and the line attachment points.  Since the end of the boom travels a larger arc, the forces are exponentially lower and can be managed by existing cleats and smaller hardware.