Roger Strube    Roger H Strube, MD

THE UNIQUE SAIL CONTROLS OF THE DRAGON

I designed the systems that control the Dragon’s Wings so that she could be sailed single or short handed. It has always been my feeling that all boats are one or two person conveyances. A vessel that is too complicated or to large to be managed by one or two people will not be used very often. It is a big plus to have the room and facilities to allow guests to cruise comfortably for a weekend or, for really close friends a week or so but the boat and it’s systems must be manageable by one or two people.

My goal was to minimize the number of control lines in the cockpit while allowing ease of sail trim adjustment with minimal effort. With the notable exception of the Nonsuch Unimaran most vessels with this primary goal can’t get out of their own way under sail. The Dragon has rod rigging and a rotating mast similar to all high performance beach cats. Millennium Dragon was designed with an air draft of 62’ so that during nasty off shore conditions she could travel from port to port on the Intracostal Waterway. She carries a large square top main sail (approximately 600 sq. ft.) with full battens. The sail is stored in the “rain gutter” boom between the “side curtains” held up by Lazy Jacks. The main has a 2:1 halyard and is hoisted (usually hand over hand) with assist of a Lewmar #44 electric winch located at the helm station. The main halyard passes through two Lewmar Rope Clutches, one at the spar and the other near the Lewmar Electric Winch. The tack is lashed to the mast just above the goose neck. The main has two reef points and a Cunningham grommet. Once the main sail is hoisted luff tension is controlled using a 4:1 block and tackle Cunningham. This control line is lead down to the deck then turn through a large high strength turning block back to the port side of the cockpit at the helm station. A Lewmar Rope Clutch secures its position near the electric winch.

The Cunningham and hydraulic system described above control the shape of the mainsail. The large square top and full battens provide an extremely efficient and powerful main but a significant portion of this power could be reduced if a non-rotation mast had been fitted. Most non-rotating sail boat masts disturb the air flow across the low pressure side of the sail casting a “wind shadow” of up to 20 percent of the leading edge (luff). A tier drop rotating mast reduces this loss of power significantly. Small beach cats sometimes use a SS yoke pinned to the mast and swinging under the goose neck and boom. A line, sometimes with a small block and tackle is used to limit the rotation of the mast relative to the boom. Larger racing trimarans and catamarans use a torque strut protruding either fore or aft of the base of the mast and controlled by block and tackle to port and starboard. This controls mast rotation relative to the position of the vessel, not the boom or sail. It works but requires more crew, more attention and more lines on deck. Both these systems have problems with the forces generated at the goose neck where some sort of universal joint is located a little aft of the sail track. All the force of a loaded mainsail are carried through this goose neck which at times, especially while tacking, causes a violent slamming full lock to lock rotation of the mast from side to side until the tack is completed. I wanted an easier way to control mast rotation and maintain a relatively constant angle between the mast and the boom. The rotation controls had to be between the mast and the boom. 

The Profurl roller furling jib clew leads to one of two through bolted sail tracks on the bridge deck. I use the outer track for easier cruising. The jib sheets run from the jib clew through the adjustable car back to mechanical Lewmar #44 winches on each side of the bridge deck. The winches are self tailing. The big boat roller cars are controlled using slide adjustment lines that run from the car/block to a turning block at the end of the sail track. The line then turns 180 degrees and runs aft back to the cockpit through smaller Lewmar Rope Clutches. This provides fore/aft adjustment of the trim point. The clue may be barber hauled in or out by rigging temporary snatch blocks on the inner track car or side deck screecher track car. The roller furler drum control line runs from the drum to the starboard side of the bow where it turns 90 degrees through a double cheek block and runs aft along the starboard deck through fair leads mounted on the stanchions. At the position of the traveler/bimini mount a double cheek block turns the line 90 degrees toward the #44 electric Lewmar winch mounted on the middle of the aft cross beam (back of the cockpit). Between the cheek block and the winch the control line passes through a small Lewmar Rope Clutch. In light weather the sail is simply rolled up by hand. In heavier air the electric winch is used.

The Dragon carries a screecher at the end of an 8’ bow sprit. This is a thick walled SS pipe with a locking pin at the forward cross beam and water stays at forward (roller furler) end. The water stays travel from the bow weldment to each bow just above the water line. These water stays are 5/16 SS stranded wire with pressed end fittings. The screecher is raised using a 2:1 halyard that exits the starboard side of the mast and runs through a Rope Clutch prior to reaching the deck plate turning block below. The halyard then turns toward the cockpit to reach a winch for final luff tension adjustment. Once up and adjusted for tension the Rope Clutch on the mast is engaged taking the additional downward pressure off the mast rotation bearing. The screecher Profurl drum is attached to the end of the bowsprit. The roller furler drum control line runs from the drum to the starboard side of the bow where it turns 30 degrees through a double cheek block and runs aft along the starboard deck through fair leads mounted on the stanchions. At the position of the traveler/bimini mount a double cheek block turns the line 90 degrees toward the #44 electric Lewmar winch mounted on the middle of the aft cross beam (back of the cockpit). Between the cheek block and the winch the control line passes through a small Lewmar Rope Clutch. In light weather the sail is simply rolled up by hand. In heavier air the electric winch is used. When deployed the sail is trimmed to adjustable sliding big boat cars on heavy duty tracks located on deck amidships at the toe rail. The sheet then travels aft to a large double turning block near the deck attachment point of the overhead traveler. The sheet then turn 90 degrees inboard to Lewmar #44 self tailing winches located on the port and starboard back rests at the side of the cockpit.

Millennium Dragon also carries an asymmetrical spinnaker. This sail uses a single part halyard that exits the mast on the starboard side, runs through a Rope Clutch, down to the deck then back to the cockpit. As this sail is hoisted in a sock winching is never needed but this lead makes assistance from the cockpit possible. The tack for this asymmetrical sail is attached to a bridle that runs from bow to bow through large Lewmar blocks. The bridle line is secured to one of the two available deck cleats at the bow. The sheet for the spinnaker uses the same deck track/block used by the screecher when it is flown. The sheet then travels aft to a large double turning block near the deck attachment point of the overhead traveler. The sheet then turn 90 degrees inboard to Lewmar #44 self tailing winches located on the port and starboard back rests at the side of the cockpit.

There are large self bailing deck stowage lockers forward adjacent to the fore deck trampolines. These lockers are used to store the sails when they are not in use.

Additional pictures with some additional comments may be reviewed by clicking on the film strip below. Other sections of this site cover other topics. The next section on “Sailing the Dragon” explains how the gear described above has propelled this vessel to a maximum speed of 17.9 knots.