No doubt you'll get better explanations from those with much more experience than I, but to quote from Lin and Larry Pardy's "Storm Tactics Handbook"; "Hove-To means your boat is no longer sailing forwad. It is stopped and making leeway with its bow about 50 degrees from the wind. Heaving-to is thus essentialy a way of stopping your boat in the water so that it sails neither fowards nor, perhaps more importantly for the rudder, backwards.
Hope this helps some.....Tony C.
<hr width=100% size=1>There are 10 kinds of people, those who understand binary and those who don't.
To heave to, sail close hauled, tack the boat without releasing jib, leave or lash helm to leeward.
Boat should sit roughly close hauled, moving slowly forward.
Why? Very comfortable way of stopping. I often do it while reading the course before a race start or between races. Everybody else seems to charge up and down while we just bob up and down in more or less the same place.
If you have a large genoa up it's not a great idea because it's backed againt the spreaders.
Some modern fin keel boats won't behave properly and need trim of main adjusted.
<hr width=100% size=1>my opinion is complete rubbish, probably.
To achieve this the normal method, if sailing along with both sails set, is to back youre Jib by steerin through the wind, & then steer back towards the wind. The effect of this is to have the jib & mainsail working against each other. the boat has minimal movement through the water although it will still be affected by leeway.
Its a balancing act between a backed jib trying to push the bows one way and a mainsail/rudder combo trying to push the boat the other. Get the forces from each right and you sit 'comfortably' at a constant angle to the wind.
How easy it is depends alot on your boat, long keel, fin keel, displacement etc as well as sail areas of main and jib.
To heave-to, tack without releasing the jib, then as the boat comes onto the new tack use the rudder to turn towards head to wind. A bit of fine tuning of sails should leave you in a stable position.
Apart from the explanations as to how to do it. Heaving to, provides a respite from perhaps making way in a heavy sea. You can simply do it for lunch, cup of tea, a loo break or simply to take stock of a situation, if you have sea room. The boat will (usually) sit reasonably calm in the slick that it creates to leeward. If you heave to on starboard tack it has obvious advantages.
...a seamanlike way of stopping the boat at sea for whatever reason, done as well described above. Most boats will lie much more comfortably in a rough sea when hove to as the sails reduce rolling, and as the boat is making little headway, pounding and slamming are very much reduced. this makes it easy to stop for a brew, a meal, or to effect running repairs when something has come adrift. It is also one of the best ways of riding out a blow offshore when the going gets rough - provided the wind is not so strong as to need to take sail off altogether - when it becomes a case for the sea anchor.
its also quite useful if you have atidal 'gate' to clear such as the Portland Race, and you arrive too early due to increasing wind strength... as happened to me last summer. Coming up from Exmouth heading for Weymouth, we planned to arrive off the Bill to catch the inshore passage. On a forecast 3, this shopudl ahve worked nicely. No one quite explained where the F5 came from, but it got us there 2 hours too soon. A comfortable couple of hours hove to a couple of miles west of the Bill, and the race had calmed down enough to allow us to continue safely into Weymouth.
A very useful strategy, and one every skipper should know how to do safely with his boat - not every modern configuration will heave to all that easily, without a fair bit of juggling with sails and helm. some like th main sheeted well in, while others need it slacked well off, while with others the helm angle can be fairly critical.