Global Solo Challenge: Sail changes on an offshore racing boat and the crossover of sails
by Global Solo Challenge 19 Sep 2021 00:21 AEST
Sail changes on an offshore racing boat and the crossover of sails © Global Solo Challenge
Sail crossover is a term used to refer to a boat's combination of sails for all conditions. Each sail has a range of use, beyond which a smaller sail will replace it.
The points where the first sail needs to be replaced for the second indicate sail changes. The crossover diagram shows us the overlap points between the sails and the appropriate moments for sail changes. At the crossover point of the sails we will have situations where two alternative sail combinations are valid. Changes must be made if we expect conditions to vary in favor of one combination or the other.
The wider the point of overlap between the sails, the more our sails suit is wide and flexible. If, on the other hand, the overlaps are very limited, it means that when the angle or intensity of the wind varies we are called to frequent sail changes. In fact, as soon as we leave the ideal range of use of a sail, with a limited overlap compared to the next sail, we have to make a sail change.
Using an out-of-range sail is not something to aim for, but there are variable weather situations where reducing the number of sails changes becomes an advantage. In fact, when we have clear all the possible combinations of sails for our boat, we must also have clear the times required for the manoeuvres. Some sail changes may require you to without a headsail until the new sail is hoisted. If our changes become very frequent, we unnecessarily waste time and energy.
The range of use of the sails
By range of use of the sails we mean the minimum and maximum wind and angle for which a sail is efficient. When we are out of these parameters we are called to sail changes. It may not be a question of sail changes but of canvas reductions. The mainsail reefs are the most obvious example, but there are other sails that can be reefed or reduced in area. On the Mini 650, for example, the solent usually has two reefs. Even the large spinnaker can often be reduced to a medium spinnaker thanks to a zip. On the Class40 the staysail may have a reef point.
On cruising boats it is also possible to furl the genoa and use it partially furled. In case performance is not our priority it is a very convenient thing. The sail usually has small circles that indicate three levels of reduction, as for reefs. Some cruise boats, especially in the Mediterranean, do not even have the possibility to hoist a staysail. Worse still, many cruising boats have no realistic way of hoisting a storm jib.
This is really unacceptable, but the problem is that the boats leave yard without the possibility of rigging an internal forestay. Nowadays it is possible to make a textile forestay (Dyneema) that can be put to rest when we do not need to use the staysail. The sail can be left hooked or removed from the deck depending on the navigation. The storm jib can be hoisted immediately above the lowered staysail. This solution is found on racing boats and cruising boats prepared for the high seas.
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