The yacht struggles to windward, climbing wave crest after wave crest. The side deck has long been dragging through the water. The last few metres upwind still have to be done under full sail. But it's no fun, the profile of the mainsail is far too deep. In order for the helmsman to maintain control at all, the sheet is fully fished, and the cloth is just killing loudly in the downwind of the jib. A glance at the bow reveals the next construction site: the crescent-shaped, oversized sag of the forestay is clearly visible.
In short: none of the usual trimming measures are having any effect. The crew tried everything: The backstay tensioner, outhaul, main and jib halyard were pushed to the limit - or rather, as far as they could go. Because with the standard tackle, the trim range on many cruising yachts is already exhausted from 4 or 5 Beaufort at the latest.
A standard undersizing is undoubtedly annoying, but can be rectified relatively easily. It is often not even necessary to completely replace the existing fittings. A few additional blocks, some cordage and the gear ratio of the boom vang, cunningham or backstay tensioner can be multiplied. But every additional gear ratio means that more ropes have to be moved. And each additional block increases the friction and thus reduces the efficiency of the transmission.
In order to find the optimum combination, it is first necessary to take a look at the possible alternatives. There are basically two systems to choose from for tackles: the classic pulley block, as we know it from the mainsheet, and a cascade of hinged runners, also known as a potency pulley block.
Both systems have special advantages. You can find out what these are and how they can be used most efficiently on board inYACHT 5/2012, on newsstands from 15 February.
Hauke Schmidt
Test & Technology editor
