Join Date: Jul 2000
Thanked 233 Times in 220 Posts
Rep Power: 18
Re: Reefing with Furling Sails
With roller furling sails and attempting to sail above a beam reach - once you roll-up more than 25% to 30% of the sail (area), .... all those 3D curved surfaces and where that 'point of maximum draft' is located, all that makes a boat 'go' ....... are all rolled-up on that foil; what you have left flying is nothing but 'flat' .... even to the point of dead flat (like a piece of plywood), especially if you dont release/ease some clew tension.
A dead-flat sail is going to develop very little POWER to 'punch' into and through BIG waves.
When reefing (any kind) its always better (IMO) to 'power up' with a slightly released/eased outhaul ....... double-line slab-reefing, roller reefing ... doesnt matter (impossible with single line reefing!). Reef very deep if you need; but, add some power by controlling (not overcontrolling) and easing the clew to 'power up' what you have flying.
Rx: When going above a beam reach, if all have up is 'dead-flat', youre going to be dead-slow and your keel/hull will have 'zilch' lift to windward.
For upwind, reefing really is to ONLY reduce heel and to regain helm balance ... most go too far and also tighten up on the outhaul which further reduces POWER. FLAT is a speed shape (for flat water), full draft even when reefed or deep reefed is for POWER in BIG waves.
Those who have 'conventional' non-roller reefing, can control their helm balance with halyard tension.
Last edited by RichH; 12-27-2014 at 05:23 PM.