You measured the bearing, converted it to magnetic and pointed the bow. Halfway across, the island is off to one side. The bearing was fine. The wind did two things to you on the way, and each one has its own fix. Here is how to see them, measure them and correct for them.
The short version
Weathercocking. The kayak swings up into the wind, so you stop pointing where you meant to.
Leeway. Even pointing perfectly, you slide downwind. You can't feel it from the cockpit.
The skeg holds your heading. Aiming upwind of your bearing holds your COG. A transit tells you if it's working.
Heading and COG are not the same thing
Your heading is where the bow points. Your course over ground (COG) is the line you actually travel over the bottom. In flat calm they're the same. Put wind across a crossing and they split apart, and the island ends up wherever your COG goes, not your heading.
Wind pulls them apart in two separate ways. Most paddlers lump them together as "the wind pushed me off," which is why their fixes only half work.
Weathercocking
- What happens
- The bow is held by the water it pushes into. The stern sits loose and gets blown downwind. The kayak pivots and the bow swings up into the wind.
- What it changes
- Your heading. You stop pointing at your bearing.
- How you notice
- You keep sweeping on one side just to go straight.
- The fix
- Skeg down until the boat tracks without corrections. With a rudder, steer slightly away from the wind.
Leeway
- What happens
- The wind pushes on you, your body and the hull above the waterline. The whole boat slides sideways while it moves forward.
- What it changes
- Your COG. You point correctly and still arrive downwind.
- How you notice
- You don't, from the cockpit. A transit or a back bearing shows it.
- The fix
- Aim off: steer a few degrees upwind of your bearing so the drift carries you onto the target.
Fix the heading first
Sort out weathercocking before you judge your leeway. If the bow is wandering up into the wind, everything you see on a transit is a mix of both problems. Skeg down, get the boat running straight, then look at the drift that's left.
Crossing Lab
The scenario: you're crossing to an island with wind on the side. Set the crossing distance, where the wind is coming from, and your leeway angle. The sketch shows where you land if you hold the bearing, and the heading that puts you on the target instead.
- Pick a wind direction. A beam wind (straight across) pushes you sideways the most. A quartering wind does less. Dead ahead or behind does almost nothing sideways.
- Drag the leeway angle. Nobody can tell you your number. It depends on the boat, the load, you and the wind strength. Start small and see how fast the miss grows.
- Read the cards. How far you miss by, and the heading that fixes it.
Where do you land?
simplified: steady wind, no currentThe lab treats leeway as a fixed sideways angle, scaled by how much of the wind is across your course. Real water adds gusts, waves and current. Use it to get a feel for the size of the error, then let a transit give you the real number on the day.
Finding your angle on the water
You can't look up your leeway. You measure it, and the tool for that is a transit: two features ahead of you, one behind the other, like a lighthouse with a hill behind it or a tree on a point with a notch in the ridge beyond.
- Skeg down first. Get the kayak running straight on your heading without sweeps.
- Line up a transit on or near your target, before you leave the shore if you can.
- Watch the near feature against the far one. If the near one slides downwind, you're drifting downwind. If they stay locked together, you're on the line.
- Aim off a little upwind and watch again. Keep adjusting until the transit holds. That's your angle, for that wind, in that boat, today.
- Check behind you too. A back bearing to your launch should stay your course ±180°. If it creeps, you're drifting.
No transit? Aim off on purpose
Sometimes there's nothing to line up, or the visibility is poor. Then make the error work for you: aim deliberately upwind of the target. When you hit the shore, you know the target is downwind, so you turn and follow the shore to it. Aim straight at it and miss, and you won't know which way to turn.
Worked example: Tobermory to Flowerpot
From Dunks Point to Flowerpot Island the bearing is 029°M on the training chart, about 1.7 nautical miles. Say there's a west wind blowing across the crossing.
- Weathercocking swings your bow left, up into the west wind. Skeg down until you stop fighting it.
- Leeway pushes you east, toward the right of your line, and past the island's south end into open water.
- The fix: steer a few degrees left of 029°M. At 5° of leeway that's 024°M. Then use a transit on the island to fine-tune it.
- The cost of ignoring it: 5° over 1.7 nm is about 0.15 nm, roughly 275 m. That's the difference between landing at Beachy Cove and paddling the outside of the island looking for it.
Bearing measured on the training chart from our Level 2 course. Always measure your own on your own chart.
Three ways it goes wrong
Every time the island drifts off, you turn the bow back toward it. You paddle a long curve downwind and arrive late, from the side, often against the wind for the last stretch.
Sweep strokes fight weathercocking, not leeway. You can paddle perfectly straight and still slide sideways. Pointing straight is not the same as a straight COG.
Drop the skeg all the way in a light wind and the bow can start falling off downwind instead. Set it so the boat tracks neutral, then aim off for what's left.
Check yourself
Want to plan crossings properly?
Aiming off for wind is a few minutes on our Level 2. Navigation Level 2 goes further: wind and current together, course to steer, and full crossing plans on real Canadian charts, with live Saturday sessions in Hamilton or on Zoom. Navigation Level 1 is included.
Related: Chart datum: the line every number on your chart is measured from
0 comments