Farr 11s
2007 May 5
May 2007
I was first struck by the fact that this hull has a small amount of bow overhang. We have come to expect plumb bows in our racing yachts. I like a little bit of bow rake as it helps push buoyancy forward and at the same time adds a lot of deck space around the jib tack. But I was not sure why the Farr office added bow rake to this design. I called. The bow rake is there to allow the tack of the code zero to be forward of the jib tack without requiring a minimum bowsprit, and at the same time the overhang pushes buoyancy forward so the fine bow does not dig in when the boat is sailing in waves.
The D/L of this design is 67.8. The LOA/DWL ratio is 89 percent. The L/B is 3.26. Stability will be provided by the canting keel with 2,400 pounds of lead in the bulb. Given that this keel cants it will not provide the lift necessary to offset the sail-force loads to drive the boat upwind. This resistance to leeway is provided by asymmetrical foils in daggerboard configuration, swept 15 degrees and located just aft of the canting keel. The foils are canted outboard so that when the boat heels they are near vertical for maximum efficiency. Note the high aspect ratio to these foils. The keel cants 45 degrees each way. Imagine how you could improve your stability if you had the ability to move your ballast CG four feet to weather. The keel canting mechanism is activated by an electro-hydraulic pump. The Farr office has the advantage of extensive experience with canting keels on its designs for the Open 60s and Volvo 70s. There are twin rudders.
The rig is based upon skiff rig concepts with spreaders swept 25 degrees and no backstay. This makes jibing the big "fat head" main easier. This frees up crew for manipulating the canting keel in tacking and jibing maneuvers. One of the most interesting things about this rig is that the drawing shows the cap shroud going continuous to the deck while the two intermediate diagonals, D-2 and D-3, run discontinuous to the chainplate. There are masthead and fractional chutes shown. The bowsprit extends to allow huge masthead asymmetrical chutes to be carried. It makes no sense of designs like the Express 40 and the Farr 11s to use I, J, E and P for sail area. There is just too much area in that big main to ignore it. The upwind SA/D listed in the promotional material is 44, while the downwind SA/D is listed at 102. That should be enough.
This boat is being built by Premier Composite Technologies in Dubai. Hull No. 1 was due to launch in April and another boat has been ordered. The hull is carbon fiber skins over a honeycomb core. The keel fin is carbon fiber. The auxiliary is a 15-horsepower outboard that retracts into a well that opens to the cockpit for access. This is an unusual custom boat.
Racer
I was first struck by the fact that this hull has a small amount of bow overhang. We have come to expect plumb bows in our racing yachts. I like a little bit of bow rake as it helps push buoyancy forward and at the same time adds a lot of deck space around the jib tack. But I was not sure why the Farr office added bow rake to this design. I called. The bow rake is there to allow the tack of the code zero to be forward of the jib tack without requiring a minimum bowsprit, and at the same time the overhang pushes buoyancy forward so the fine bow does not dig in when the boat is sailing in waves.
The D/L of this design is 67.8. The LOA/DWL ratio is 89 percent. The L/B is 3.26. Stability will be provided by the canting keel with 2,400 pounds of lead in the bulb. Given that this keel cants it will not provide the lift necessary to offset the sail-force loads to drive the boat upwind. This resistance to leeway is provided by asymmetrical foils in daggerboard configuration, swept 15 degrees and located just aft of the canting keel. The foils are canted outboard so that when the boat heels they are near vertical for maximum efficiency. Note the high aspect ratio to these foils. The keel cants 45 degrees each way. Imagine how you could improve your stability if you had the ability to move your ballast CG four feet to weather. The keel canting mechanism is activated by an electro-hydraulic pump. The Farr office has the advantage of extensive experience with canting keels on its designs for the Open 60s and Volvo 70s. There are twin rudders.
The rig is based upon skiff rig concepts with spreaders swept 25 degrees and no backstay. This makes jibing the big "fat head" main easier. This frees up crew for manipulating the canting keel in tacking and jibing maneuvers. One of the most interesting things about this rig is that the drawing shows the cap shroud going continuous to the deck while the two intermediate diagonals, D-2 and D-3, run discontinuous to the chainplate. There are masthead and fractional chutes shown. The bowsprit extends to allow huge masthead asymmetrical chutes to be carried. It makes no sense of designs like the Express 40 and the Farr 11s to use I, J, E and P for sail area. There is just too much area in that big main to ignore it. The upwind SA/D listed in the promotional material is 44, while the downwind SA/D is listed at 102. That should be enough.
This boat is being built by Premier Composite Technologies in Dubai. Hull No. 1 was due to launch in April and another boat has been ordered. The hull is carbon fiber skins over a honeycomb core. The keel fin is carbon fiber. The auxiliary is a 15-horsepower outboard that retracts into a well that opens to the cockpit for access. This is an unusual custom boat.
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