SETTING AND SHEETING SAILS
55.1: Changing Sails
When headsails or spinnakers are being changed, a replacing sail may be fully set and trimmed before the replaced sail is lowered. However, only one mainsail and, except when changing, only one spinnaker shall be carried set at a time.
55.2: Spinnaker Poles; Whisker Poles
Only one spinnaker pole or whisker pole shall be used at a time except when gybing. When in use, it shall be attached to the foremost mast spar (as defined in The Equipment Rules of Sailing).
55.3: Sheeting Sails
No sail shall be sheeted over or through any device that exerts outward pressure on a sheet or clew of a sail at a point from which, with the boat upright, a vertical line would fall outside the hull or deck, except: (a) a headsail clew may be connected (as defined in The Equipment Rules of Sailing) to a whisker pole, provided that a spinnaker is not set; (b) any sail may be sheeted to or led above a boom that is regularly used for a sail and is permanently attached to the mast from which the head of the sail is set; (c) a headsail may be sheeted to its own boom that requires no adjustment when tacking; and (d) the boom of a sail may be sheeted to a bumkin.