Demystifying the roles of the Trimmers and Grinders
Mainsheet trimmer
We all know that the rudder is used to steer the yacht, but did you know that when speed is key (racing), that steering will slow you down? Why? Well put simply, the more angle put on the rudder, the more drag is creates in the water, and therefore the slower the boat will go.
The solution to maximising your speed whilst manoeuvring is to use your sails and that’s where the sail trimmers step in. It’s fair to say that the sail trimmers often have more control over the direction of the boat than the helm!
This is easily demonstrated if you watch a yacht approaching a windward mark, on a windy day. Unless the trimmer dumps the power out of the mainsail, the helm will find it totally impossible to bear away downwind at the mark.
Basic trimming techniques:
Turning away from the wind (bearing away) – you need to effectively pivot the boat around the keel and this is done by pulling the jib in tight and the letting the main out which moves the centre of effort of the sail plan forward and which helps to push the bow away from the wind.
Turning into the wind (heading up) – you need the centre of effort to be towards the back of the boat which will head the boat up to wind. This is done by letting out the jib and trimming the mainsail in.
Race start tactics - include keeping the mainsail fully trimmed, unless directed otherwise, being prepared to dump the entire sail if required and trimming hard and fast on the final approach to the line to ensure the boat is at full power at the gun.
Genoa/headsail and spinnaker trimmer
Research has proven that the jib/genoa provides 80% of a boat’s driving force. It therefore follows that the person trimming this sail has a responsible job and has to be chosen carefully. With the jib/genoa the objective is to maintain the best windward performance at all times using the luff tell-tales as a guide. The leeward one should be flowing horizontal all the time whilst the windward one can be allowed to lift intermittently, or in heavy conditions continually.
Trimming the spinnaker requires total concentration so that the sail is always flown in its sweet spot, this particularly important in light conditions, the spinnaker trimmer should always have the spinnaker sheet in their hand and therefore their ‘fingers on the pulse’.
How much pressure in the spinnaker (sheet tension) is an indicator on how high or low to sail the boat. Increased tension means the spinnaker is ‘loaded’ and the helm can sail a lower course to the next mark. Decreasing pressure on the sheet indicates that the helm needs to sail a closer angle to the wind and increase speed.
Grinder
More about power than glamour, this essential position demands strength and endurance to power the winches that are used to trim or hoist the sails. If you’re looking for action, this job is the most physically demanding in the team.
Peak effort, involving large bursts of energy are required during pre-start manoeuvring, tacking and gybing - America’s Cup (match racing) grinders can burn through 4000 calories during the race!
Working in partnership with the trimmers, the grinder provides the power to allow the trimmer to concentrate on the sails.
Experienced grinders listen to the tactical discussions between the helm and tactician and anticipate the next move, often turning the handles before the call comes from the trimmer.