This is my point on the learning curve: tacking in sequence to the shifts, learning to see or time them and learning when a gust should be tacked on to get a 'double lift'. hmmm
meg
Quick primer for someone on the rail.
As mentioned before the race committee sets the upwind mark for the average wind direction. The wind shifts back and forth (more on why later) as you sail up the course. Lets say that on average you can sail 35deg from the true wind direction.
If the wind is blowing directly from the mark, you can sail 35deg down from the mark (ie 35deg angle from a line straight to the mark from the start line) on each tack
When the wind shifts so that the tack you are on lets you sail a course closer than 35deg to the mark you are getting LIFTED upwind towards the mark. This a good because it means you sail a shorter distance to get to the mark.
When the wind shifts so that the tack you are on forces you to sail a course more than 35 deg from the mark you are getting HEADED away from the mark.
And a wind shift that Lifts you towards the mark is a lift or a lifter and vice versa.
So why are there such windshifts? Well tons and tons and tons of words have been written about this. But fundamentally there are 4 causes:
1. Puffs and lulls - puffs are windspeed increases and lulls are windspeed decreases. Both are caused by turbulent "knuckles" of wind (like in a tumbling stream). and when they touch down onto the surface of the water, they spread out like the fingers of your hand because the wind in the middle is spinning faster than the wind at the edges that is being slowed down by friction with the ambient air. So the wind at the edges points outwards from the center of the puff. And its a header on one side of the puff and lift on the other
2. Geography. - wind gets funnelled by buildings, trees, shoreline etc. So it "bends" around geographies. That's why sometimes a wiley skipper will sail a "headed" course to get to a strong lift on the opposite tack ( a header on one tack is a lift on the other and vice versa).
3. Weather systems - all weather systems spin as well as move horizontally. So as a weather front crosses over the course, the wind direction shifts in accordance to the front
4. Coriolis Effect - As the wind blows in a straight line over the course of the day it gains momentum. But the earth is spinning underneath it. So over the course of a day, it slowly shifts. In the northern hemisphere this means it slowly clocks (follows the direction of the clock) and in the southern hemisphere it backs (backwards from the direction of the clock).
Once your boat handling and boat speed are good, doing well in racing is about identifying which combination of wind shifts apply and exploiting them to minimize your course distance and maximize your speed.
and from President Eisenhour
Remember this: getting a lift feels like fun, but your objective is to be on the lifted tack not to be getting lifted.
Consider the textbook scenario that never happens during real life -- true wind is steadily, predictably oscillating between 350 and 010.
Typical mistake many of us make is to tack on the shifts, when you really want to be tacking on the midline: You're on S as the wind starts at 350 and you get lifted as the wind swings all the way to 010 ... feels great ... then it starts backing, so, sensing the header, you tack onto P at around 008, and you get lifted continuously as the wind swings back to 350, then it starts veering again and you tack at 352, so you're on S all the way from 352 up to 010... lather, rinse, repeat. It feels great coz you're always getting lifted, but you're doing the wrong thing.
What you want is to be on S whenever the wind is between 000 and 010, irrespective of whether it's swinging right (lifting you) or swinging left (heading you). You want to be on P whenever the wind is between 350 and 000, irrespective of whether it's swinging right or swinging left. So, when the wind is steadily oscillating between 350 and 010, you want to tack as it crosses through 000. Very hard to learn, even harder to do in the real world.
- Damp freddie writes : what this means is that when you started sailing off the start line say on STB with a wind at estimated 350 , course 305, you were HEADED. The wind shift lifts you immediately BUT UNTIL IT CROSSES 000 due N, you are loosing ground to your shadow who spotted it was headed and tacked onto port atestablishing a heading of 035 being headed progressively to 045 and tacking only then . While on STB it all feels great and it's a big scallop.
Now you do exactly the wrong thikng on the other side. If it swings all the way to 010 then you are correclyt on starboard, but feeling the oscillation going to favour port you tack on the shift when you still have 8' of gain to windward average . You are in effect sailing !backwards ! in a curve which takes some time to swing into average forward movement to the mark ie over 000.
So you learn the shifts before you go out or in a longer race out there. You watch your heading and it will be best 045 to worst PRT 055 say on PRT and then 315 and 305 on STB, You tack at a heading of 050 Header, off PORT over 00o WInd going right or 300, header wind going left.
Further: SAILING UPWIND -FASTER
Having a good beat to windward is one of my favorite things on the water There is nothing quite like steering a keel boat that is ‘in the groove’ and making great VMG to windward. Here are some thoughts about techniques, goals and priorities when you are driving a boat upwind.
General rules of thumbTo steer a boat fast upwind, you must be able to guide that boat efficiently through a series of changes in the wind and water.
Therefore, it’s key to anticipate changes that are coming. If you don’t know about a puff until it hits your sails, you will be constantly in reaction mode.
Keep your head out of the boat so you can make proactive adjustments before or as the puff hits. * To improve your ability to anticipate changes in conditions, assign one of your crewmembers to watch out for puffs, lulls, waves and flat spots.
On small boats, this lookout often must be the skipper because the crew may not have a very good view of the race course. On larger boats, it’s usually a crewmember sitting on the rail. * If your boat is big enough to have a tactician, find a good one you trust so you can focus entirely on steering without having to look around very much. If your boat is small enough that you must steer and do tactics at the same time, practice steering by feel so you can look around a lot and still keep going fast.
* It’s very important to keep talking with your mainsail trimmer for two reasons: 1) only you can feel what the boat needs through the rudder; and 2) he or she controls the sail that has the biggest impact on the balance and speed of your boat, which is critical for steering. *
If you (the helmsperson) are also trimming the mainsail, never cleat the mainsheet unless you must. Holding the mainsheet helps you take the pulse of the boat and allows you to make quick adjustments needed for steering fast.*
If you are steering a bigger boat, don’t get mesmerized by the instruments. They can be helpful for keeping the boat sailing near its potential, but there is no substitute for good feel and judgment.* Most helmspeople like to point high when they are steering. There is nothing so reassuring as the knowledge that you are sailing higher than the boats around you. But remember this critical rule about steering upwind: “Go fast first and worry about pointing later.” If you try to aim your bow too high before your foils are working efficiently, you’ll be slow.
* Once the boat is going well, keep trying to trim the sails (especially the main) harder and point higher. As soon as you feel the boat start to slow, ease the sheet a little and bear off slightly to build speed- PRESS on the JIB or SEND a MAN DOWN TO TRIM THE GENOA.
Now. start the cycle again. When the boat feels fast, trim harder and point higher. If it feels like you are slowing down, ease and get going. * Practice steering upwind. The best way to learn is speed-testing with one other boat. This gives you a great chance to try different steering techniques and get immediate feedback by watching how you do relative to the other boat.
Beating in light air
When you are sailing upwind in light breeze, fous on speed and distane to the next wind or towards the goal....Try sailing a little too low and fast rather than too high and slow. If you try to point and sail on the high side of the groove, all it takes is a lull or a wave or a header to kill your speed and force you to accelerate all over. *
Try to manufacture at least a little bit of windward helm so you will have some “feel” to help you steer. Adjustments to increase helm include adding more rake, heeling the boat more, moving crew weight forward, pulling the traveler farther to windward, and so on.* It’s important to stay focused on steering the boat fast. This is not easy since most light-air races are long and frustrating. As a famous Olympic and America’s Cup sailor once said, “If you don’t finish the race with a splitting headache, you probably didn’t concentrate hard enough on steering.”* Move the rudder as little as possible. On a tiller boat, consider using a ‘frying pan’ grip on the hiking stick to keep the rudder straight and quiet
* Set up your sails and rig so they are more forgiving. You want full, powerful, draft-forward sails with twist that are good for footing rather than pointing. This makes your sailplan less critical and helps you steer the boat in the groove much more easily.
Heavy air and waves
When it’s windy, one of the biggest problems for the helmsperson is having too much windward helm. This can be a steering nightmare because it is physically demanding and hurts your boatspeed. So work on reducing helm by using less mast rake, keeping the boat flatter, moving crew weight farther aft, dropping the traveler to leeward, flattening the sails and so on.
* You should usually bear off and power through chop,
but as the waves get bigger you need to start steering around each one.
In general, head up on the face of each wave and bear off down the back side. In dinghies, move your weight in sync with this – out and forward as you bear off over the wave and then in and aft when you hit the trough and head up again.
* Waves (and flat spots) seem to come in sets, so make sure that someone on your boat watches for these and gives you a warning. Point higher in the flat spots and then bear off to power through the unavoidable waves.* When you’re overpowered is a good time to steer by heel angle. Point the bow high enough to keep the boat on its feet. And when you want to turn the boat, you must absolutely help a lot with sail trim since weight placement and even the rudder often have little effect. •
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