2016 Dudley Dix DH550 Catamaran

The DH550 cruising catamaran started life as a design commission received by Dudley Dix from catamaran builder Philip Harvey. Phil was cruising with his family and wanted to move up to a larger boat. Dudley had too much work in progress to be able to take on the new design so the two agreed a cooperative basis to do the design between them. Dudley brings 30 years of design and boatbuilding experience into the project and Phil brings 15 years of professional boatbuilding and catamaran experience. Between them they have produced a cruising catamaran with striking good looks and high-performance potential.

Construction is a further development of the radius chine plywood concepts that Dudley has drawn since the early 1990’s. These concepts started with the monohull Didi 38 “Black Cat”, which he built to test the construction method then sailed across the South Atlantic three times. Since then he has developed other performance oriented monohull designs of similar concept, from 21 to 42ft LOA. As of October 2006, nearly 300 boats to this method are in build or sailing worldwide.

As successful as the radius chine plywood monohull designs have been, this project has shown that this construction method is even better for catamaran hulls than it is for monohulls. The hulls of Phil’s DH550 were quick to build and are fair and pretty to look at.

This is a big and powerful boat and it is intended for cruising the oceans of the world. To take on that role, it has 1m (39”) bridgedeck clearance to minimize slamming in big seas. The hull/bridgedeck junction has received particular attention to ensure that the loads imposed by rig and ocean are properly transmitted and shared between them. Carbon composite chainplates are laminated to the inside and outside of the hull and spread the rigging loads down into the hull skin, longitudinals and bulkheads. The mast stands on top of a major transverse bulkhead that is configured as an I-beam to spread the compression load laterally into the hulls and is tied into longitudinal bulkheads that spread the load fore/aft into the bridgedeck structure.

The interior arrangement is modeled around 2 cabins in each hull, sharing a common heads/shower area that separates them for privacy. That makes this boat suitable for 4-couple bare-boat charter work. An alternative hull accommodation arrangement will also be offered, with a larger owner’s cabin in one of the hulls.

Bridgedeck accommodation is spacious, with separate galley, steering, navigation, dining and relaxation areas. Forward of the bridgedeck accommodation is a small forward working cockpit that gives access to the base of the mast and all control lines. Aft there is a large relaxation cockpit protected by the roof overhang, with easy access to transom steps down to swim/boarding platforms and a full-width aft bridgedeck platform.

The underbody is clean and easily-driven, with long waterline for high performance. A vertical daggerboard in each hull gives windward ability along with the ability to enter shallow water. In August 2011 we have added the option of fixed cruising keels as well. The shaft-mounted rudders extend to below the propellers to protect them from damage.

The rig has an aluminium mast with double diamonds to keep it straight. It is held by upper and lower single shrouds that are angled well aft to properly support it in all wind directions. Headsails are sheeted to the forward bridgedeck and the mainsail is sheeted to the cabin roof over the aft bulkhead.

The DH550 is a boat that offers comfortable fast cruising. It is already proving popular, with four sold and in-build before the first boat was launched. This will be the first in a series of radius chine plywood catamaran designs that will be developed by Dudley Dix and Philip Harvey.

The principal material used in the build is timber, Brazilian Mahogany in structural areas, Western Red Cedar for stringers and framing core areas between skins and  Okoume veneer plywood from Joubert Plywood in France, a high quality product with thin veneers ensuring high resistance to elements. Complimenting this there is an extensive use of Fibreglass and epoxy,  saturating  and  laminating  and  structural  types,  depending  on  application. 

Most joinery is also strengthened with structural epoxy filleting creating a sense of "overkill" in terms of strength but this only gives one an extra security. The finished product is epoxy painted  internally  and  high  quality  polyurethane  over  two  coats  of  saturating  epoxy externally,  result  looking  like  a  boat  produced  in a  mould. 

The yacht  has  a  fair share of custom 316 stainless steel components beautifully built by Salie Jacobs, a master craftsman from South Africa who has 50 years of experience of faultless work behind him. The main windows  are  custom  shaped  shatterproof  glass  30%  tinted  set  in  Sikaflex  and  doubly waterproofed with an Aluminium "eyelid" also set in Sikaflex around the window edges.

Powered by twin Volvo diesel D2-55 inboard engines of 55hp each - Sail Drives - 2 x 3 Blade Folding Propellers - Engine Hours: 650 - Fuel Tank Capacity: 930L - Water Tank Capacity: 900L.

Fuel: There are two stainless fuel tanks each carrying 400 litres, gravity feeding fuel to two more 65 litre tanks situated in close proximity to the motors. 

Water: The boat carries an impressive 900 litres of water in two stainless steel tanks which can inter connect or be separate, one serving the Port hull, the other Starboard, each with own pressure pump, i.e. two systems. Each hull has a hot water system heated either with the motors running or with 220 Volts when connected to shore power or by running the generator.

• 3 double cabins with a larger owners cabin layout.
• 2 x electric heads and showers.
• Approximately 2m headroom throughout in cabins and saloon.
• CRUISAIR air conditioning/heating throughout. 3 x 16,000 BTU units and 1 x 27,000 BTU unit - 75,000 BTU total.
• TV/CD/DVD/Radio SAMSUNG/FUSION system.

• Pressurised fresh water system
• Hot and cold water
• Fresh water maker
• SMEG 5 burner gas hob and over
• Microwave
• 2 x Isotherm refrigerators
• Freezer
• BOSCH washing machine
• BOSCH condenser tumble dryer

Sparcraft in Cape Town built rig from two 11 metre lengths of appropriate Aluminium sections, 22m high mast. Standing rigging is stainless steel Dyeform wire.The boom is also built in Aluminium with haystacks and lazy jacks with a separate cover. The self tacking jib is on a rope fed Profurl furler.

• Aluminium SPARCRAFT mast.
• Fractional rig.
• Lazy jacks.
• NORTH SAILS Slab reefing main (2016).  Area 101.5.
• PROFURL furling genoa (2016).  Area 43.5.
• NORTH SAILS Genaker (2016).  Area 1601.
• NORTH SAILS Storm jib (2016).  Area 23.4 / 16.5.
• Dyeform standing rigging (2016).
• Running rigging (2016).

• House Batteries (Dry) - 1000Ah 2015.
• 2 x 12v Engine Batteries (Wet) - 100Ah 2016.
• Electrical Circuit - 12V.
• Shore Power.
• Generator - WESTERBEKE 9.4Kva 2016 (300 hours).
• LED Lighting throughout.
• 4 x Solar Panels - E20 Blue Solar 327W 61CV.
• Battery Charger.

• 3 blade feathering propellers.

• GARMIN log/speedo.
• GARMIN depth.
• GARMIN wind speed and direction.
• LEWMAR (Whitlock) autopilot, and handheld.
• GARMIN GPS/plotter with AIS.
• Navigation lights - Masthead and deck level.

• LEWMAR electric windlass.
• 35kg stainless steel main anchor.
• 100m stainless steel anchor chain.
• 20kg galvanised kedge anchor with 15m anchor chain and 100m warp.
• Warps and fenders.
• Hot and cold deck shower.
• Davits.

• Emergency tiller.
• 12 x life jackets (2016).
• 4 x harnesses (2016).
• Lifebuoys (2016).
• Dan buoy (2016).
• Floating light (2016).
• Floating line (2016).
• Drogue (2016).
• Search light (2017).
• Foghorn.
• Radar reflector.
• 8 man VIKING liferaft (Service due 11/19).