The 35XS

offshore racing boat
offshore racing boat
offshore racing boat

Project Detail

Specifications:
LOA 10.668 m (35′ 0″)
LWL 10.363 m (34′ 0″)
Max Beam 3.505 m (11′ 6″)
Draft 2.743 m (9′ 0″)
DSPL 2812 kgs (6200 lbs)
SA (up) 79 m2 (850 ft2)
SA (dn) 206 m2 (2220 ft2)

Performance Ratios:

Dspl/Lgth – 70
SA/Dspl – 44
SA/WS – 4.1

This summer (2007) saw the launch of the first 35XS offshore racing boat in Hungary. The builder/owner put the boat together from one of our kit-plan packages and did an absolutely fantastic job. He and his crew did most of the construction themselves and even built a very nice wet-out machine for wet-pregging the fiberglass material (click here to view the construction process). They are now very much enjoying their boat with their sights set on a first place finish in the 2008 Blue Ribbon Series on Lake Balaton.

The 35XS is a unique hybrid of ideas combining the radical speed potential of the 2XS-11000 one-design day-sailer and the proven offshore race performance of the VG-Mount Gay 30. This design was primarily conceived for the high-end PHRF/IRC market but has strong one-design potential. Whatever the venue, there is no doubt that the ahead-of-the-art 35XS will turn some heads on the race course.

The hull form is a clean and exceptionally fast shape with a narrow waterline beam and a low wetted surface. This philosophy produces a boat that will dominate the competition in light to moderate breezes. In the heavier stuff, as the residual resistance on a hull form increases proportionally with the speed of the boat, the 35XS boasts a length/beam ratio of 4.4 indicating a relative reduction in wave making drag. Combine this trend with a with a displacement/length ratio of 70, a moderately low prismatic of 0.530, a fine entrance angle at the bow with narrow “U” sections forward, and a wide and gentle run aft. The result is a powerful and easily driven hull with the potential for both a strong windward performance and the ability to readily plane.

The sail area/displacement ratio can be thought of as a measure of power to weight. This design will have and a projected upwind SA/DSPL of 44 and downwind SA/DSPL of 110, again indicating a great upwind performance and a superb planing potential. The fractional rig is carbon fiber with 23 degree swept-back spreaders and carries a non-overlapping jib. Due to the highly roached main there is no backstay to hang up on. To compensate for the fore and aft loads from headsails a unique and user-friendly mast-head runner system has been designed. Several rig variations are being considered at the moment based on client needs and local wind conditions.

E-glass and Kevlar over a foam or balsa core, vacuum bagged in an epoxy resin, is the prescribed method of construction for the hull and deck of this offshore racing boat. Carbon fiber uni-directional material is used in areas of high loading such as the keel grid, chainplates, and in critical transverse framing and bulkheads. However, an all E-glass boat could be built to increase the economic one-design potential of this design for a relatively small increase in the overall weight.

The deck configuration is again a trickle-down from the Mount Gay 30, which has proven itself under fire to be a well conceived working platform for both round-the-cans and offshore racing. The large open cockpit will allow the helmsman and trimmers to do their jobs without the hassle of traffic jams. The cabintop adds to the aesthetic value of the boat as well as being a functional base of operations for the pitman. It also provides a relatively spacious interior.

The keel has a draft of 2.743m (9 feet) and is fitted with a trim tab that gives the 35XS an amazing windward performance. The fin can also be retracted for convenient trailering purposes. The fin is a state-of-the-art, high-lift, laminar flow, foil section. The low center of gravity, T-bulb configuration features our latest and very fast “shark” geometry. The fin/trim tab is a carbon/foam construction with a stainless steel internal strut bolted into the lead bulb.

The interior of the 35XS offshore racing boat has a very functional and clean finish, well attuned to offshore races or the rigors of round-the-cans racing. There are four fixed berths 2m in length. The galley, forward and to port, has a sink and a one-burner stove. To starboard there is a removable cooler, the top forming the navigation table. Storage lockers are built in overhead and below the bunks. Aft of the companionway is the engine box housing an inboard Yanmar 20hp diesel with Saildrive.

When racing offshore, sailing shorthanded, or just day sailing with friends, a full range of stability is available using the water ballast tanks. The system operates via an electric pump with a hand pump backup. The flow controls are located in the cockpit just forward of the traveler, providing quick and convenient access to the trimmer. The total capacity of the port and starboard wing tanks is 1052 liters, or the weight of five crew members per side.