Mainsail twist
Mainsail twist is controlled by the tension in the leech (trailing edge of the sail). More leech tension means less twist (and more power). Reduce the leech tension to increase twist in heavy air.Leech tension is primarily controlled by the mainsheet, boom vang, backstay and leech cord (small-diameter line in the leech of the sail itself that is cleated on the sail near the clew). The first two controls pull down on the boom. More mainsheet or vang tension puts more downward pull on the boom, tensioning the leech. The backstay bends the middle of the mast forward and the top of the mast back. More backstay tension in heavy air does two good things at once; flattens the sail and loosens the leech. The leech cord tensions the leech independently of the other controls and should be loose in heavy air.The recommended setup for heavy air is to tighten everything except the leech cord. Easing the mainsheet or the traveler in the gusts also helps to depower the mainsail.These suggestions are based on the assumption that your rig is properly adjusted. If the mast does not have enough rake and pre-bend, you might not get the full range of sail adjustment that the running rigging should provide. Check with someone who knows the correct rig settings for your boat. Good luck.Peterh23 "Raven"