The question of staysails - how to make them work for you
by Andrew Dove, Area Manager North Sails Caraibes on 26 Apr 2009

Staysail doing a great job on a Havkat 31 SW
Though most modern sloops have a furling headsail and a mainsail, staysails are far from atypical, although those added to boats often appear to be of little use.
The usage is not clear as the majority of cruising boats see this sail as a heavy weather windward sail, but too often the sail is too small and flat to give any drive into a formed sea.
However on a purpose-designed Cutter rig, the Yankee/staysail combination can function very well. Both sails accelerate the wind and, combined with the rest of the rig, make a logical upwind and reaching choice.
In the 16th century we find numerous references to the staysail. It was discovered that you could set a triangular sail on such a stay, and this turned out to be an important breakthrough in the development of sailing ships with respect to balance and performance.
In the glory days of IOR racing, staysails and bloopers were in their heyday. I am certain that the names and shapes of these sails go beyond my memories of tallboys; dazies and Genoas (staysail).
However often on a boat designed for a single headsail where an inner stay - either permanent or demountable - is installed, the windward usage of a staysail can be limited. Many boats I work with, for reasons such as the foredeck hatch position or the windlass, have their inner stay set well back. For aesthetics or to full opposite a runner, the mast tang can be fairly low down the rig. As the sail moves aft, the sail has to be set in front of the spreaders and the available sail area reduces. This is often exaggerated by a dinghy on the deck, a radar on the mast and an available luff reduced by a full metre due to the usage of a furling system.
The resulting sail is at the best small and if not optimized, minute. As a heavy weather sail the boat must have reduced sail area but must have enough power up forward to manoeuvre and master the oncoming seas.
A self tacking staysail, generally set on a boom, is practical, but again to set the boom in front of the mast and to use a common sheeting system reduces the LP by another 10%.
I have built a few fully battened hanked on staysails with a positive roach. The bottom batten, as on many beach cats, replaces the boom well. This solution is lighter and the roach allows the sail both to twist and maximises surface. All this isn’t to say that a typical staysail does not have a windward role but care, I believe, is needed if this sail is to function well.
Where this sail does have a role to play is off the wind—and, and its usage in Americas Cups or on modern race boats is the proof. Under spinnaker on certain points of sailing, the staysail helps air flow and moves the centre of propulsion forward and reduces rudder angle and the chance of broaching.
The ideal downwind staysail for racing may not be cut or made in the same material as the upwind sail, but for cruising purposes we can always compromise a little. (However if the boat is equipped with heavy Dacron sails, the dual function of the staysail may justify a lighter high tech staysail which as small may not be very expensive.)
When under spinnaker or gennaker when you decide to try the staysail an important tip is to take one’s time. Check your boat speed for a good few minutes before hoisting. Check your rudder angle if you can. Then hoist and set the staysail, settle down and check the trim, then over another extended period check hull speed and rudder angle. Generalities are often floored but between 90 and 120 degrees apparent, the staysail should pay and make sailing more comfortable. Again try this under good conditions first, smooth seas and moderate winds.
In light airs the staysail often does not twist and the spinnaker does not fly out enough. In this case the staysail will have a negative effect on performance. In heavy weather the staysail if maintained but eased to the limit of backing can avoid broaching under spinnaker or Genoas.
My understanding of the types of staysail mentioned earlier is:
The tall boy has an LP of 100 to 110% and has a high hoist. The clew is generally high to allow a sheeting position off the boom to broaden the sheeting angle.
The dazy was of Dutch origin and has an LP reduced to 80 to 85%. This sail is generally built light.
The Genoas staysail has a reduced hoist often 70% of available hoist but an important LP of 80 to 100%. Such a sail suits a boat with less stability.
Naturally the typical windward staysail is a fourth version.
As in any situation where a number of sails interact as with a ketch, trim begins and is controlled by the forward-most sail and the sails aft adapt to the sail in front. When the interaction works, there are speed advantages and boat handling becomes comfortable.
However the balance and critical angle can be fine. If you enjoy cruising with an MPS then thought should be given to a free flying light staysail to make this point of sail both more comfortable and better performing. The free flying option requires little extra equipment other than a quality halyard and a light weight sheet.
If you want a little more control over this sail a modern single line Code 0 furler is ideal. For this the sail has to be finished with a double roped luff. Normally my thoughts are to minimize material but a downwind staysail is a positive addition if you enjoy a boat that balances and performs well. It certainly is another toy.
Andrew is based in Guadeloupe
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