The headsail is usually the most important item in a yacht’s sail wardrobe. Not only does it typically provide the lion’s share of the power, it’s generally the first sail that the moving air comes in contact with. It has a cleaner airflow than the mainsail (no mast to cause turbulence at the leading edge) which enables the sailboat to point a bit higher, and it increases the speed of the air passing over the main. The ease of tacking and reefing are key considerations when choosing and sizing a headsail, and so is durability, especially on a cruising yacht where it’s usually left exposed for the whole sailing season. Headsails don’t have an easy life!
Jib or genoa?
Headsails are available in many different sizes and are usually measured as a percentage of J, which is the distance perpendicular from the mast to the point where the forestay meets the deck. This is the length of the foretriangle base. If a headsail is longer than J, it overlaps the mast and is known as a genoa, if it is shorter than J, it’s non-overlapping and called a jib. The ‘overlap’ is the amount that the sail exceeds the J measurement. For example, a 130% genoa will measure 1.3 times the J length, and it will overlap the mast by 30% of the J measurement.
Is a single forestay enough?
Our standard headsail configuration is a sloop rig – a single forestay with a jib or genoa. This gives the best pointing ability and it’s the lowest-cost option. Depending on where you sail and the type of sailing you do, the sail could be a self-tacking jib or a 120% to 135% genoa. You may have noticed that on colder days the wind feels stronger than the same wind speed on warmer days. This isn’t entirely due to the greater difference between air temperature and body temperature, it’s also because warm air is less dense, and hence lighter, than cold air.
A temperature drop of 3°C increases air density by about 1% and in cold weather, the denser air exerts more force on the sails. If you are planning to sail in areas that regularly experience stronger and colder winds, like northern Europe or Canada, then a 120% genoa would be preferred. If you are keeping your yacht in warmer climes where the wind is generally hotter with lower wind speeds, you may wish to consider a 135% genoa.
Benefits of a solent rig
The most popular option on our range of deck saloon yachts is a solent rig (which also has the less attractive name of a “slutter” rig because it’s a cross between a sloop and a cutter), 98% of all our yachts have been built with this rig since 2010. Instead of a single headsail, we fit an inner forestay, giving two forestays to fly two headsails. The forward stay has a genoa and the inner stay has a 97% jib, which is usually self-tacking.
The advantage of the solent rig is that you have a full-sized jib which can be used from around 10 knots (force 3) true wind and it will tack itself on a track, making it much easier to sail to windward up narrow rivers or in crowded areas. Tacking is as easy as turning the wheel; there are no sheets to pull in with every tack, no scrabble for winch handles, no winching. The jib is the primary sail for going to windward but when sailing off the wind – and also in light airs, when sailing close-hauled in open water – you still have the option of using the larger, more powerful genoa.
As the wind increases, rather than reefing the genoa by partly furling – which ruins the shape of the sail in no time and makes it less efficient – it can be fully furled and the jib unfurled. This gives you an efficient sail configuration up to around a force 7. After that, you can reduce the headsail area further by starting to furl the jib.
The advantage of the solent rig is that you have the sails you need ready to go, so it makes your sailing safer, more comfortable and faster.
Imagine coming down to your sloop rigged boat, the big genoa attached ready to go, the forecast is for light winds – there is no need to swap to the smaller sail that you keep in the forepeak. Once out there, you realise the winds are stronger than expected, have changed direction or you change your plans and need to reduce the headsail. You have two options, partly furl the big genoa and suffer poor pointing, increased heeling and worse performance; or you retrieve the jib that’s in the forepeak, remove the big and probably wet genoa, and feed in the new smaller jib which is a job for both you and your companion. Once you go through the rigmarole of changing sails the winds may well go light again.
With the solent rig you can furl the genoa and unfurl the jib in less than two minutes, on your own, all from the safety of the cockpit. You always have the best sail for the conditions you find yourself in. Having reduced sail area if, later on, you round a headland, island or reach a waypoint and need to bear away, you can furl the jib and get the full power of the genoa and have a great sail to your destination.
Downsides of two headsails
One downside of the solent rig is that the inner forestay needs to be close to the outer forestay, which does make the flow of air over the luff of the inner sail a bit more turbulent. Moving the inner stay further aft (as in a traditional cutter rig) would make the size of the jib less practical, reducing it to the size of a storm jib. Also, if we were to bring the inner stay aft, the deck would need reinforcement, which would intrude into the large, open space of the forecabin. An internal brace would be needed in the middle of the berth to take the loads – not very practical. Moving the outer stay forward onto a bowsprit would increase the overall length of the boat, which might make your marina or harbourmaster happy as you’ll have to pay them more.
Having the inner and outer forestays close together means that when tacking the genoa, it needs to be furled so it can pass between the two stays, then unfurled again afterwards. For cruising boats like ours that don’t get into competitive tacking duels very often, we feel it’s a small price to pay for the added versatility – especially if you have an electric winch or furling system. When you do find yourself tacking to windward you can make longer tacks or just use the self-tacking jib if furling and unfurling the genoa is too much hassle. Sailing into the wind increases the apparent wind so in practice you’ll find that the jib works very well in a wide range of true wind speeds and the genoa will only be used in light winds anyway.
The hybrid option
Another downside of a twin headsail rig is that it effectively doubles the cost: two sails, two stays, two furling units and you still don’t have an offwind sail configuration for light winds. So why not choose to keep the standard single forestay and have either a self-tacking jib or a smaller 110% genoa, to keep the headsail easy to tack (or very easy in the case of the self-tacking jib) and opt for an asymmetric sail on a removable furler?
The most popular sail for this purpose is a 150% (or more) code zero. This is like an oversized genoa that is used in winds up to 13 knots and set on a removable furler attached to a bowsprit. While this sounds and is a possible solution as a code zero works between 2 and 13 knots and the jib most perfectly from 12 knots onwards, you may find yourself between a rock and a hard place in 10-15 knots of wind – the kind of breeze people love most. You may find the jib on the small side and only effective upwind or the code zero too much of a handful and you’re unable to point to windward.
In practice, however, the extra work of attaching the code zero is rarely done when it’s cold or wet (and if it’s wet the sail needs to be dried out to prevent mould and mildew) which is why most of our owners opt for the solent rig.