Roller furling headsails.
After a roller furling genoa has been run out, the furling line should be secured so that there is no slack in the system.
If the line is left loose and the boat is sailing downwind it is possible that the action of the sail causing the furling gear to rotate backwards and forwards can pull slack line to the front of the boat. A possible consequence of this is that the last few turns of the furling line on the drum may become loose and when the time comes to stow the sail away you may find that the slack has allowed one or more turns to pass over a later turn (a little like a riding turn on a winch).
If this happens it can be very difficult to release the load on the sail, the only approach is to unwind a few turns of the furling line from the drum.
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