Gennaker or Code Zero: which sail to choose to turn off the engine when cruising?

The warm season is upon us, and with it we begin to think about our first cruises and sailings in good weather, perhaps enjoying some healthy off-engine sailing with our cruising boat. If your unit is not poorly equipped, sail-wise, to deal with wide swells, perhaps because it is equipped only with a mainsail and jib, it may be time to consider a Gennaker or Code Zero. In fact, with these sails, the range of situations in which we can turn off the engine and just enjoy the sound is expanded. Of the boat gliding on the water.

What to choose though between Gennaker and Code Zero? Let’s start with an assumption: as you will read, these are two different sails in terms of shape, size, materials and angles of use. If we plan to make a larger investment, with both we would cover virtually every need for a cruising boat in order to sail as much as possible. Alternatively, one needs to make a choice based on one’s experience, sailing skills, and ideas on how to use the boat.

Both can be rigged with simple systems such as stockings or whips, which allow even a few crew members to use these sails. The stocking is used for gennakers, which can also be cocked on a whip as long as they have a fairly skinny shape. Code Zero and A0, on the other hand, will always be armed with a blender.

The gennaker sketch

The gennaker is an asymmetrical carrying sail, that is, the two foils are not equal (as in the spinnaker) but the entrance one is longer. The sailmakers who produce them code them from A0 to A5. A1, A3 and A5 are sails for sailing downwind in various wind strengths, A0 is a crosswind sail in light winds or downwind in strong winds, A2 and A4, on the other hand, are sails with a rounder cut made for sailing at angles resting as much as 160 degrees.

Which of these might be suitable for cruising? Probably the A2, an already stronger-weight sail, which can be hoisted even up to 20 knots of wind and allows good angles at the lean-to. A sail that we can safely rig with a sock to hoist and lower it even with a small crew.

It will come in handy when we sail in a brisk breeze at full slack; it will get us to a possible downwind destination by gybing a smaller number of times than another sail from carrying gaits. In the A4 version, we will instead have a sail with similar characteristics, but slightly leaner and stronger for use in winds above 20 knots. Odd-numbered cuts, on the other hand, rather than for cruising, may be suitable in racing where specific sails are needed for each gait. When cruising, the narrow slack can be covered by other solutions.

The sketch of the Code Zero

Let’s start with a difference about which there is sometimes confusion: the difference between Code Zero and A 0. They are both sails that can be used on a furler but, simplifying, the former looks more like a large jib/genoa, the latter like a skinny gennaker. If we are talking about a Code, it is a sail that allows us to sail even upwind wide in winds under 10 knots, and crosswind even in cooler winds.

The A0, on the other hand, struggles more and performs less well at tight angles, although with little wind you can use it, while it performs better on the traverse with little air or on the slack with a strong wind. What to choose for the cruise?

The A0 might be a more versatile sail, usable in a somewhat wider range of conditions than the Code. Much depends, however, on the characteristics of the boat, what overall equipment we have, and how we want to sail. If we decided not to buy a gennaker and put all our eggs in one of these two furling sails, the A0 would be the best choice. If, on the other hand, we have a gennaker and maybe our boat with little wind is not very fast, here is where the tails can come to our aid to make it walk faster even upwind.

Technologies and materials

Gennakers continue to be made of nylon, only the A0 is also made of more valuable laminated material being a sail that is used at tighter angles. On the nylon asymmetric side, there are no huge technological innovations that have emerged in recent years; furlers for gennakers have been developed, but they are sometimes solutions that penalize the sail shape a bit. The ideal for cruising use still remains the sock.

On the other hand, as far as Code zeroes are concerned, the materials used range from laminates to stitched ferzi, to full-fledged membrane sails. The big technological innovation was the introduction of the reinforced luff, which absorbs some of the halyard load (and is also used in A0s).

The so-called “cable less” technology (pictured above) that allows Code Zeroes to be made without anti-twist cable, making a more efficient sail, with less catenary in the leading edge and able to lighten the load coming onto pulleys and halyards. A solution that was designed for racing but can definitely come in handy when cruising as well.

Mauro Giuffrè