Cruising (Asymmetrical) Spinnakers

Sailing with my cruising (asymmetrical)  spinnaker is great on light breeze days when I am sailing downwind for several miles.  When I had the cruising chute made, I specified that I wanted a full 180% spinnaker with the foot of the sail modified to give the asymmetrical shape - - that is to add a partial panel to the bottom of the sail to extend the tack corner down – rather than cut the leach of the sail up.  My way actually makes the sail larger rather than smaller than a “normal” spinnaker.  This is perfect for light breeze days with winds between 5 and 10 knots.  As the wind gets up to more than 10 knots, this asymmetrical spinnaker is too much sail though.  And, the boat quickly can become overpowered…… this can lead to a broach…

Spinnaker broaches – even with a cruising spinnaker – are scary and no fun at all.  Double that if you are single handing your sailboat.

Broach = most typically happens when a boat is on a broad reach with spinnaker set and there is an overpowering weather helm.^[1] This may be due to excessive heeling, swell that causes the rudder to be partially lifted out of the water, or because the stem digs into a wave causing a strong lateral force. The boat will come quickly across the wind with too much sail set. It can also happen on a close reach where it is typically precipitated by sudden waves.^[2] With an inattentive helmsman it can be a consequence of a gybe, which can be a dangerous manoeuvre even when performed under controlled circumstances. When it happens unexpectedly and the helm isn't corrected, the heading of the boat may veer into the wind causing a broach.

 

The worst broach I have experienced on Snickerdoodle happened one day when I was single handing.  At the marina, the wind seemed to be in the 5 to 10 knot range out of the SW.  So, I decided to sail to Whiskey Rock (about 8 nm to the NE).  It seemed a perfect day for a spinnaker broad reach with the cruising chute.  So, I rigged everything up and motored out of the marina.  I raised the mainsail and then changed course to the SE on a broad reach – with the Navico tiller pilot steering the boat.

Up on the foredeck, I raised the cruising spinnaker in its “Chute Scoop” sock, made sure everything was all set, and raised the sock to deploy the spinnaker.  The wind was light as I was in the lee of Leiberg Point.  Back in the cockpit, I could see that the wind was quite a bit stronger coming out of Idlewild Bay (from SW to NE).  “This is going to be great,” I thought, seeing that there were many white caps marching across my bow about 500 meters ahead.

As I came out from behind the lee of Leiberg Point, the first 20 to 25 knot gust hit the sails… AND heeled Snickerdoodle over until there was water washing against the portside main cabin windows.  Can you spell decks awash?  Snickerdoodle rounded up with the spinnaker still in the water and then righted herself as wind pressure moved forward to the point where both sails were luffing.  “Oh boy,” I thought.  “This will be a fast reach to Whiskey Rock… and I fell off to a broad reach.  The second strong gust hit the sails at just about the same time.  Snickerdoodle was knocked down so far that the sheet and tack adjuster line were both under water.  In fact, the whole portside coaming was under water and water was freely flowing over the coaming and into the cockpit.  “Hmmm, this isn’t good,” I thought as I noticed there were no hatch-boards in the companionway.  “If we tip much more, water will begin to flood the main cabin.”

Luckily, Snickerdoodle again rounded up head to wind and righted herself.  “Time to douse that spinnaker,” I decided.  And I cautiously went forward and pulled the downhaul line on the Chute Scoop - - - and successfully doused the spinnaker.  It was a terrific – and fast – sail to Whiskey Rock under mainsail alone.

Here are a couple options for if you get caught with the cruising spinnaker up and wind building to uncomfortable strength.  First, you can douse and lower the spinnaker completely.  Another option might be to partially douse the spinnaker by hauling the downhaul line part way down.  I saw a friend of mine sailing this way a couple weeks ago.  It looked pretty neat.

So, don’t be afraid to sail with your asymmetrical spinnaker.  But make sure that you are in fairly light breezes until you get used to that big, powerful sail.  Enjoy

barnaclebillholcomb@gmail.com

Old Halyard Sheaves

Do you own a sailboat that is older than about fifteen or sixteen years old?  When was the last time you inspected the halyard sheaves in the masthead casting?  There is a good chance that your boat's manufacturer used some sort of plastic or nylon for those halyard sheaves.  There also is a good chance that the sun's ultraviolet light has damaged those sheaves over the years.  The sunlight makes the plastic become brittle and the "shoulders" of the sheave break off - - ultimately, the sheaves won't hold the halyard anymore and the halyard slips off the wheel and becomes jammed between the side of the sheave and the masthead casting.  Raising (or more importantly lowering) the sails will be difficult if not impossible.  I postponed and rescheduled a private sailing lesson yesterday for just this reason - - the halyards simply were too difficult to operate.

Here is a photo of one of the original halyard sheaves from Snickerdoodle (on the right).  You can clearly see the damage to the shoulders of the wheel.  On the left is the new silicon/bronze sheave that I replaced the original sheave with.  Of course, I replaced all four sheaves.  Snickerdoodle was about 16 years old when I made this change.
So, if you haven't inspected your masthead sheaves recently, it is probably past time that you did.  Imagine what would happen if your were not able to douse your mainsail or a jib sail in an emergency situation......  BTW - the new silicon-bronze sheaves were machined for me by a friend with a metal lathe.  Cost for the materials and the labor was not that much more than the cost of four new plastic sheaves...... AND the metal sheaves won't be affected by sunlight.

Cruising Spinnakers

Cruising Spinnakers

I have had a “cruising spinnaker” (asymmetrical spinnaker) on Snickerdoodle for many years.  And, I’ll have to admit that this sail doesn’t see much action.  I’ll fly it maybe half-a-dozen times per year.  BUT, it is a great downwind sail for broad reaching.

Here’s how I have the sail rigged –  

The spinnaker halyard is a separate line rove through a block on the very front of my mast head cap fitting.  Catalina Yachts actually designed the cap fitting with a “crane” that puts the block ahead of the forestay so that hoisting and dousing this sail is pretty easy.

There is a tack adjustment line that is rove from the sail’s tack corner through a block that’s secured to the stem fitting and then back to a cleat on the outside of the portside cockpit coaming.  With this adjustment line I can trim the tack corner higher or lower as needed for good sail shape.  Lower is for close reaching - - while higher is for broad reaching.

There are snatch blocks secured to the “T-rail” just aft of the forward part of the stern pulpit.  The two spinnaker sheets are rove through these snatch blocks – one sheet to each side of the boat… then the sheets are trimmed using the primary winches and cleats.  The loaded sheet extends from the sail’s clew corner directly to its snatch block.  The lazy sheet goes around the forward side of the forestay and rests on the bow pulpit – before extending back to the other snatch block.

To make hoisting and dousing easier, I’ve got a “Chute Scoop” – a sort of sausage bag with up-haul and down-haul lines.  Hoist the sail inside the Chute Scoop.  When everything is ready, pull the up-haul line to deploy the spinnaker.  When you are ready to take the sail down, pull the down-haul line to “bag” the sail before lowering.

Trimming this big sail is pretty easy - - remember that I’m only using this sail in breezes of about 12 knots and lower.  If I’m on a broad reach, I adjust the tack adjustment line so that the tack corner is about five or six feet above the deck.  I have a climber’s carabineer secured to the tack corner and clip it to the forestay to better control sag away from the centerline of the boat.  Sheeting the clew corner is straight forward.  Sheet out until the sails shoulder starts to fold in – then sheet in until the sail fills fully.  See-sawing the sheet back and forth keeps the sail pulling at its maximum.

I like jibing this sail like a big flag out in front of the forestay.  Here’s how it goes… when you are ready to jibe, start turning the boat and release the loaded sheet.  This allows the clew of the sail to “fly” like a big flag out in front of the boat.  As the boat turns and the mainsail jibes, start pulling in on the new loaded sheet.  The spinnaker will sort of turn inside-out.  Trim the sail and you are on your way.

On light breeze days when I want to sail for a considerable distance down wind, I’ll rig the cruising spinnaker to one side of the boat and my drifter jib with a whisker pole to the other side.  The wind angles off the drifter into the spinnaker making everything really work well. 

Another fun thing to do with the cruising spinnaker is to motor upwind on light breeze days, then set just the cruising spinnaker and sail downwind.  Since I have not set the mainsail, the spinnaker stays filled even on a downwind run.  It’s lots of fun.  In fact, learning to trim the cruising spinnaker without the mainsail up is much easier.