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The 56' Motor Sailer "SHIRAZ"

56' Ketch SHIRAZ - Kasten Marine Design, Inc.

Interior Profile & Arrangement | Deck Plan | Perspective Forward | Perspective Aft | Perspective Portside
Shiraz Original Sail Plan | NC-Ready Structure | Structure Development

Copyright 2000 - 2015 Michael Kasten

General Concept

SHIRAZ is designed to be an efficient motor sailer for construction in aluminum. Named after a robust yet refined, always dependably pleasant wine, SHIRAZ will certainly live up to the attributes of her namesake. Intended for ocean passages and inland waterways the gaff ketch SHIRAZ will certainly accomplish the task in comfort and in style. With a sheltered 'midship wheel house, one need not be offended by the elements, be they too warm or too cool. With Herreshoff-like classic lines, SHIRAZ will turn heads wherever she goes.

Hull Shape

Particulars are as follows:

A graceful single chine hull form was chosen in order to achieve the maximum performance per dollar. How so?

If designed properly, a single chine hull will have outstanding performance. With a simply built and therefore economical and easily driven hull form, one can afford to make the vessel a bit longer and realize some very real performance gains. In other words, a rounded hull of this size could not be built for the same money, so for the same cost it would necessarily be smaller and therefore inherently slower.  Given the refined hull form of the SHIRAZ, the theoretical hull speed will be exceeded fairly easily. True hull speed is expected to be around 10 knots.

Just as with any aspect of a vessel's aesthetics, the question of chine vs. radius vs. rounded hull finally comes down to one's personal choice which, once made, cannot be argued. In this case, I believe the choice is an excellent one.

The Motor Sailing Advantage...

A Lugger or John Deere four cylinder turbo diesel along with adequate fuel capacity will give SHIRAZ the ability to function as a true motor vessel. For the ultimate in efficiency, the engine will be mated to a Sabb pitch control / reduction gear driving a Helseth Controllable Pitch Propeller. An alternate that we have developed instead uses a standard ZF gear with an AutoProp: a self-feathering, self adjusting propeller, designed to absorb all the engine's torque at any given rpm - essentially an 'automated' pitch system that allows the blades to fully feather when under sail.

Being a thoroughbred sailing vessel as well, SHIRAZ' range is not limited by her fuel capacity. Making good use of the synergy of motor sailing, range will be virtually unlimited and speed will be dramatically enhanced. Rather than having a motor vessel on which the roll stabilization will ordinarily rob the boat of speed and efficiency, the sail rig will provide a very welcome improvement to both.

56' Shiraz Under Sail in Virtual Sailor  56' Shiraz Under Sail in Virtual Sailor
Click to see larger images.
These are images of the SHIRAZ model created by Alan Winter for the Virtual Sailor program.
You can download the program, and the model, and actually sail the Shiraz...!

The Rig

The gaff rig designed for the SHIRAZ has much to offer. Simple and strong, easy to build and maintain, these are elemental virtues. The materials used for traditional rigging of this type are extremely basic: galvanized wire, anhydrous lanolin, friction tape, tarred nylon seine twine, latigo leather with waxed thread to sew up the spliced eyes passed over the masthead. Using this approach, the longevity of the rig is excellent, outlasting stainless rigging several times over.

The rounded roach to the foot of the sails on SHIRAZ is inherited from the sloops of the Caribbean.  In "The Aero - Hydrodynamics of Sailing" Marchaj has provided ample evidence that the loose footed sail is more efficient than one which is laced to a boom. I prefer the loose footed sails for a more basic reason: If the sheet is located at the end of the boom, the sail does not then impose a side load on the boom, therefore the boom acts purely as a strut. The boom can be less heavy and will be more easily handled.

As for the rake of the masts, this is another choice based on practicality. The rake of the masts causes the booms to lift as they are let out, which serves to keep the boom ends out of the water. Less obvious benefits are that the sails will be more easily lowered, and that the halyards can be used to lift a dinghy onto the cabin top more easily.

Originally designed in 2000, in 2009 the request came to revise the rig to have a Gaff Mizzen as shown above - very nice...!

56' Ketch SHIRAZ - Kasten Marine Design, Inc.
  Click for Larger Image.

The Interior

A roomy owner's stateroom is located in the aft cabin along with a head and shower. The passage leading forward contains a laundry area with washer and dryer, or alternately a spare berth can be located in the passage to starb'd. Forward of the passage is a large galley with an excellent view from the doghouse windows. The saloon settee seating will easily seat six to eight at the table. As usual, the seats will double as sea berths. Forward of the saloon is a day head to starb'd, and a privately enclosed tub / shower to port. The forward cabin provides a second stateroom for guests complete with double berth. In the forepeak is a large bosun's locker.

On deck, the pilot house can sleep two. Below, the vessel can sleep six, counting the settee berths, or seven with a berth in the passage. Of course that is too many for more than an occasional party...! The arrangement being quite open amidships for the sake of entertaining and also very private with regard to the two staterooms, SHIRAZ will accommodate two couples in excellent luxury for long term cruising.

A bathtub. A complete laundry. Air conditioning. Plenty of ice... Scheisse, what more can one ask of the cruising life?

CNC Cut Parts...

In 2009 we finalized a complete set of CNC Cutting Files for the SHIRAZ, using metric dimensioned materials.  Check out the images showing the structure under development in the following links...

56' Ketch SHIRAZ Structure - Kasten Marine Design, Inc. 
Preliminary Structure  |  Structure Export  |  Structure Development

A Larger Version...!

The SHIRAZ is sufficiently well-liked that we have developed a larger concept design at 64 feet, length on deck.  Check it out in the image below, and at the 64' Shiraz Prototype page.

65' Tern Schooner AMETHYST - Kasten Marine Design, Inc.
 More Info About The 64' Shiraz Prototype Shown Here