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The MultiRig^Ô Multihull:

The main idea behind the MultiRig^Ô concept was to design an asymmetric rigging system, which allows a better capture of the wind than the traditional sole or in-line rigs, whatever the points of sail and tack.

This potential is further enhanced when two or more similar MultiRig multihulls (particularly catamarans) are linked with each other in the same manner as train cars…

A MultiRig^Ô is composed of 3 Balestron Rigs, of different sizes, implanted as follows:

·        A smaller “ForeMast” (FM) set at the front of one of the (right or left) outer hulls.

·        A medium “AfterMast” (AM) set behind the middle of the same outer hull.

·        A larger “MainMast” (MM) set ahead of the middle of the other (i.e. respectively left or right) outer hull.

These masts shall be implanted between the internal or external sides/edges of the outer hulls, possibly on the median line.

This allows them to be fixed, in case of a catamaran, in a much stronger manner than when the “thinner” central part is holding one or more median masts.

The masts can be slightly inclined towards the central axis of the multi-hull, so that the under-edge of the boom is horizontal when it is perpendicular to the hulls axis.

The Multirig^Ô has been developed specially for the Baldakin^â Explorer range of catamarans, but it is also very suitable for other catamarans, proas and trimarans.

This presentation is based, arbitrarily, on a “right type” MultiRig, i.e. with the FM and AM implanted on the right hull.

A “left type”, with these masts on the left side, would of course function exactly in the same manner since the hulls are symmetric.

This means that MultiRig Mutlihulls can be constructed and operated indifferently on a right or left mode, except when it is constructed for a special route when prevailing winds (for example Trade Winds) will come from one direction and/or when several MutliHulls are designed to be joined together like train cars, in which case it may be preferable that the types of MultiRigs are made to alternate.

In case of an asymmetric proa, the FM and AM can be implanted on the main hull and the MM on the smaller hull, but the opposite works also (giving the same difference as between an Atlantic & Pacific Proa).   

The size and implantation of the 3 Balestron rigs, based on the standardized, scalable shape and dimensions of the Balestron rig (i.e. a boom/mast length ratio of about 60%), is calculated so that:

1.                 The sail area of the FM is between about half and equal to that of the AM and their combined sail area is approximately (possibly up to 25% more or less) equal to that of the MM.

2.                 The rotating booms do not interfere with each other

3.                 The booms, when the multihull is facing the wind, do not (unreasonably) overlap the overall dimensions of the hulls

A typical MultiRig would have the MM bearing 50% of the total sail area, with the FM 20% and the AM 30% (or respectively 40% and 60% of the other 50%, hence the 40/60 name given to such MultiRigs)

Based on a LOA to beam ratio of approximately 2, as usual in modern catamarans, the above clauses allow for the MM to be approximately equal to the hulls’ LOA, which is more or less the standard for a mono-rig.

This means that the total sail area achieved with a MultiRig multihull can be up to the double of that allowed by a single Balestron or traditional rig.

This eliminates totally the need for extra sails, such as Spinnakers or Geenakers, particularly for the downwind points of sail (but it does not prevent the use of such sails).

Furthermore, the fact that each hull supports approximately the same sail area, gives a MultiRig^Ô catamaran a balanced sail power.

The division of sails between three (independent) masts makes it much more flexible and safer than the typical rigging with 1 or 2 masts

Even if and when all the 3 rigs are not used simultaneously (for example if only those on one side are in operation) a MultiRig^Ô catamaran remains as well balanced as an Atlantic or Pacific type proa.

Further advantages of a MultiRig^Ô compared to a single or several “in-line” Balestron or traditional rigs are as follows:

·        It frees from masts the central part of the deck, thus making it available for other uses, such as a runway for ultra-light aircrafts and/or courts for outdoor sports on the larger, cruise-type “Baldakin” Explorer sailing catamarans.

·        It frees from booms some areas of the deck, thus making these areas usable to implant higher structures on these locations, such as a “mushroom-like” main control room in the “aft area” located at the stern of the port hull or, possibly, an antenna mast in the “front area”.

·        It gives the catamaran the flexibility (and traditional repute) of a three-master.