Virtual Sailing: Basic Hints

by Sailorjohn, taken from http://hangsim.com/forums/

Sailing, both virtual and actual, is actually quite simple. You can learn the basics in an hour or two...and you will spend the rest of your life learning more and more about it...and you'll never know it all. You're operating in a constantly changing environment, and you'll probably never encounter quite the same identical circumstances again. It's like flying in that sense.

First, some basics. Sailing is a matter of lift (bet the old sailors didn't know that). The sails function as a sort of airfoil standing on end. The wind moves across those sails and generates lift, and drag, just like a wing...only vertical. And that wind is called 'relative wind' as it is a vector of the true wind (what we perceive when standing still), and the wind generated by movement of the boat. To generate that lift, wind must flow over the sail as a foil. When the boat is facing directly into the wind, or nearly so...the sails 'luff', flapping and fluttering, and generating no lift...only drag...so the boat will move backwards. You must turn the boat at an angle to the wind for the sails to fill, and generate lift. The closest a modern sailboat like the Swan 82 can 'point' into the wind is about 35-40 deg off the apparent wind...and the closer you are pointing to the wind, the tighter the sails must be pulled in. When you are sailing at 35-40 deg of apparent wind, you are said to be 'beating to windward'. You can point no closer without losing your lift (the sails 'stall'). So to make progress directly upwind, you will have to make a series of 'tacks'...zigzag courses roughly 45 deg either side of true wind. That's what the AP in VS/VSF is doing when you have 'sail' clicked, and it turns away from your intended heading. It's turning to the optimum angle for best upwind lift. When you want to 'tack', you turn with full rudder through the headwind until you are the same 35-40 deg to the other side of the headwind bearing (it's generally a 90 deg turn in total). So 'tack' is both a noun (a course leg offset from wind bearing by 35-40 deg), and a verb...the action of turning through the wind to the new tack.

As you sail further away from wind bearing...around 50 deg off the wind...you are 'close reaching', and the sails should be eased out a little. When the wind is abeam, you are 'beam reaching', and sails should be eased out further. When the wind is at an angle abaft the beam, you are 'broad reaching', and sails should be eased quite far out. You might even chose to fly a spinnaker. Finally, when wind is at or nearly dead astern, you are 'running free', and sails are slacked all the way out, at right angles to the keel. Great time for spinnaker. You can turn through the wind downwind by 'gybing' to put the wind on the opposite quarter...but beware of the swinging boom! In the real world, sailors haul the boom amidships just before executing the gybe; failure to bring the boom in beforehand results in a 'flying gybe'. The results can be ugly. In the case of gaff rigs, the flying gybe is also known as the 'goosewing gybe', where boom winds up on one side, the gaff on the other...and the sail likely tearing in the middle!

As you know, VS and VSF will auto-adjust sail if 'sail' is clicked. If AP is used and 'sail' clicked, boat will automatically adjust course to avoid sailing too close to the wind. If you wish to adjust sails manually, in VS you can use the Sail panel and click and drag those 3 winches (main, jib, spinnaker) to trim. In VSF, you can mouse-click the sail itself and drag in or out. A good way to learn is to avoid AP use; steer manually, and manually trim the sails...and watch the effect on speed, and watch the little 'efficiency' icons that rise and fall on the sail indicator panel. BTW, if the VSF AP has 'collision' checked, the boat should avoid grounding...but it's not 100%, especially if the bottom gradient is steep.

Sharpy's Swan 82 is a magnificient boat; I greatly enjoy 'sailing' it...even though I prefer more traditional boats, like his Hans Christian 48, and his Minstrel (I owned and lived aboard a similar ketch in California). However, I would suggest that you start with something simpler, like the default Finn dinghy. It's small, only one sail, and reacts quickly. You'll have to shift your weight (viewpoint) to avoid capsize...but you'll see instant cause-and-effect, that a large heavy sailboat will mask.