What is the G-0?
The newest product in the North Sails G-Series group of cruising asymmetric sails is the G-0. The G-0 is a modification of the racing Code 0 and is essentially an updated "reacher/drifter" free-flying sail with a high modulus luff rope. The G-0 should be used as a furling sail and was established after a variety of North Sails cruising customers from different geographic regions requested free-flying reachers.

What is the Code 0?
The racing Code 0, developed for IMS boats, is an asymmetric spinnaker designed to fly like a huge reaching jib while just meeting the requirement of SMG = or >75% foot length so that it is rated as a spinnaker. The racing Code 0's are just deep enough to support the extra area if they are set up perfectly. Although a little finicky to use, they have proven to be indispensable weapons for ocean racing boats that are rated with asymmetric spinnakers. The effective wind range is approximately 45 degrees apparent in 3-6 knots true wind speed and up to 100 degrees apparent in 9-11 knots true wind speed.

What is the shape of the G-0?
The G-0 has been modeled after the racing Code 0 without the roach area dictated by the race rules and with reduced luff curve so that the sail can be used with more sag. These modifications have brought the SMG down from 75% to 60%. The cruising G-0 takes advantage of the cross section shaping that was designed on the Code 0 to support the leech roach, but it is more fair than the racing sail because it doesn't have to be designed to hit the SMG requirement. We believe that the G-0 will offer the cruising sailor the performance benefits of the racing Code 0 in a much more user-friendly package.

What are the notable design differences between the G-0 and Code 0?
1) The Code 0 has significantly more luff curve. Remember that no matter how hard the halyard is pulled up, this sail is going to be set on a sagged luff rope as soon as it is pressurized. So the excess luff curve will make a deeper entry than is ideal. The G-0 will have a more normal looking entry, like you would expect to see on a very deep reaching headsail.

2) The Code 0's leech is bumped to get the mid-girth out to 75% of the foot length. On the G-0 the leech is a fair curve. The bump has been cut off.

What is the wind range for the G-0?
The polar diagram above displays the range in which we anticipate the cruising sailor will find the G-0 most effective. The G-0 can be pushed into higher apparent wind angles in light air. In fact, the Code 0 racing sails, contorted with an inhauler, have proven to be effective as high as 36 degrees apparent in 3-4 knots of true wind speed. However, we anticipate that in winds less than 6 knots, 95% of our cruising customers will either be motoring or arranging to buy more fuel. In 8 knots of wind or more, the working jib will push the boat at acceptable speeds while sailing on angles tighter than 45 apparent. The G-0 will come into play when the sheets have to be eased.

At the other end of the apparent wind angle, the efficiency of the G-0 will drop off dramatically as soon as the breeze is aft of 90 degrees. But we expect these sails to be lugged as low as 115-120 simply because they are much easier to handle than a gennaker and there is a greatly diminished risk of a disaster because the sail is hanging off a tight luff rope. On broad reaching angles with the wind in the low 20-knot range, the cruising sailor can use the G-0 as a "chicken chute".

Bow Sprit Notes:
The G-0 should be set with a very tight luff rope. The sails will not furl properly if the luff rope is slack. Accordingly, the tack fixing point will be subjected to nearly the same load as the head ring. This means that the tack load on a G-0 could be 3-4 times greater than the tack load on a running A-sail. Accordingly, if you intend to set the sails on any type of bow pole, bow sprit or anchor platform that does not have a stay or fixed strut opposing the halyard, please check with the pole or boat manufacturer to make sure you will not be exceeding the loads they anticipated.