Vang is extremely useful on H23
The fractionally rigged mast on the H23 is very "bendy". Its shape can be modified under way with the running rigging to adjust the trim of the sails, particularly the main. The vang controls the tension of the luff of the mainsail. Off the wind, the boom is out over the side, so there isn't much downward pull from the mainsheet. The sail twists (evidenced by a rising boom), spilling some of the wind and reducing the drive from the sail. Tensioning the vang keeps the boom from rising, counteracting mainsail twist and presenting maximum sail area to the wind. When sailing upwind, the vang controls leech tension in combination with the mainsheet. In heavy air, increasing backstay tension bends the mast. The top moves aft and the middle moves forward. The forestay attachment on the mast does not move. The bend flattens and depowers the main. One side effect is that the leech of the main opens, increasing twist and depowering the sail. Adding vang tension or mainsheet tension closes the leech and fine-tunes the power of the mainsail. That's the general idea. You will have to spend some time on the water working with the vang to see the full effect. I suggest you get the sail trim guide that is advertised here in the HOW, it's well worth the money. Good luck. Peter H23 "Raven"
