ByteCII

The Class, with the assistance of the boat's designer and its manufacturers, has been pursuing the development of an entirely new rig concept for the Byte for nearly two years. The intent has been to broaden the weight range of sailor capable of handling the boat in heavy air while, at the same time, attempting to improve its light air performance at no sacrifice to the above. The full record of the development will not be discussed here as it is extensively covered in detail on our Byte Class International Website, www.byteclass.org

The goals were:

1. Lower the weight of sailor capable of handling the boat in heavier winds above 15 knots particularly in the 55 kg range. Picture at left.
2. Keep the boat competitive for the heavier, 65 to 70 kg, sailors. Picture below.
3. Improve light air performance up to, or beyond the level of the Laser Radial and the Europe.
4. Do all this but remain the lowest priced high performance singlehander in the world.

The rig in use today on the Finn, OK, Europe, Laser, Laser Radial and the Byte is a 50 year old concept which Ian Bruce, himself the designer of the last three rigs, readily admits to on the Website www.byteclass.org.

The female sailor in the photograph weighs 52.3 kgs and is sailing in winds of 18 knots, gusting to 22. Traveller is well down and she would not be sailing as high as a 70 kg sailor (weight does make a difference!) but her head is out of the boat, the boat is completely under control and she would be comfortable competing.

The female sailor in the photograph weighs 69.5 kgs and is not having any problem in powering up the boat in 8 knots. The Cunningham is without any tension, the traveller is slightly sheeted to weather to keep the boom over the transom corner without undue sheet tension and the leech is properly twisted, but not de-powered.

Note the closed leech on the standard Byte rig on the right. In the light conditions pictured, there is nothing the sailor can do to open that leech - and it is slow.

The sails are, essentially, triangular sails supported on masts with an even bend. The leeches are too small to generate enough pressure to open themselves up and the masts are too stiff to assist in this action which we call depowering. For many, like the Laser and Byte, the mast must be bent to flatten the sail to depower it and this can only be done with the mainsheet, or vang, using the leech. Therefore, the area of the sail, the stiffness of the mast and the resulting leech tension determine, very precisely, the weight of sailor able to sail any particular singlehander in heavier winds.

The automatic response rig

This is not the case with the more recently developed, skiff-type, self-depowering rigs. Here the sails carry large, eliptical head, fully battened sails that are hung on a masts with very flexible tips and with bend characteristics that are not uniform but rather have the maximum deflection much higher up in the mast to help produce the eliptical shaping.at the top. These rigs open and close automatically in response to increased wind loading (gusts) and depower downwards from the top. The spars are flexible enough that the Cunningham tension, acting like a bow string between gooseneck and mast tip, is sufficient to bend the mast WITHOUT main sheet tension and to thus completely free the leech. The lighter sailors pulls hard on the Cunningham in heavy air; the heavier sailors pulls less, or perhaps not at all, if they can handle the power.

The CII Rig

What is described above is the new rig for the Byte. The mast is a carbon/glass hybrid with more carbon than glass in the lower and very much the reverse in the top as an all-carbon top would be far too stiff in a laminate that could withstand abuse. The weight of the mast, tracked and with all fittings, is under 4.5 kgs and has a deflection curve considerably different to the standard of today's unstayed mast and this can be seen in the top middle pictures at left. The female athletes sailing the Byte and the Europe are both the same weight - 69 kgs. Winds in the top photo are 5 kts and, in the lower, 8+ knots

Light air

The sail area of the CII sail is approximately the same as the Europe but the Byte boom is higher off the water and the centre of effort of the sail is again higher because of the eliptical roach. For this reason, it is not surprising that the CII's light air performance is extraordinary. In 5 knots, the CII is approximately 4 to 5 boat lengths per minute faster than the standard Byte.

Moderate air

While the CII is still faster, the two rigs are closer in performance with the exception that a lighter weight sailor is able to compete far more effectively in the CII.

Heavy air

The performance difference becomes very pronounced and the boat can be sailed by crews that were previously uncompetitive in the standard rig.

Off the wind

The boat has become a sparkling performer off the wind with the reaching and downwind performance gains fairly well matching the upwind results with the exception that, even in the mid range, the CII remains markedly faster than the standard rig. A welcome plus has been that, with the inertia of the rig increased due to the height of the sail plan, the rate of roll is much slower giving the sailor more time to check an unwanted rolll to weather - quite common in this genre of boat!

Technical data: