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Why didn’t the kayaker cross the road? Ferry angles in kayaking

kayak ferrying under the seven mile bridge

The Seven Mile Bridge in the Florida Keys connects the Middle Keys to the Lower Keys. Under the bridge, the water is shallow, and it seems like the 1,000 square miles of the Florida Bay flows through the opening on the tide generating up to 4 knot currents. In a kayak, the current is swift enough to push you out to sea on an ebb tide or into the bay on flood. The common practice in a situation such as this is to find a ferry angle that prevents you from drifting out to sea and this is also a common practice with preventing leeway in cross winds. This is commonly taught as the correct practice, but is it always the correct practice? Not according to John Winters, a naval architect and canoe and kayak designer, if efficiency is the goal.

I had an opportunity to experience the differences between two approaches to currents on a kayaking trip in the Keys.

Ferry Angles

You use a ferry angles to maintain a course when currents or winds would push you off that course. It is the angle between your course and your heading and is set so that you paddle into the wind or current at just the right angle to maintain your course while making headway. You can set a ferry angle by calculating the exact angle based on your paddling speed and the current’s speed. There’s a great explanation on how to do this in John Lull’s Sea Kayaking Safety & Rescue: From Mild to Wild Conditons, the Essential Guide for Beginners Through Experts or in David Burch’s Fundamentals of Kayak Navigation, 4th. Knowing how to calculate the ferry angle is helpful for when you can’t find a range, such as in the fog, in the dark, or on long crossings, but finding a range makes setting the ferry angle simpler.

To set a ferry angle with a range, just paddle at an angle and adjust that angle so that the two points in your range stay aligned. As long as the points are aligned, you maintain your course. As your angle increases, you’ll need to increase for forward speed to maintain a decent speed along the course. Ferry angles larger than 40 degrees are very inefficient and waste lots of energy for little progress towards your destination. Even at 40 degrees if you’re paddling at 4 knots, your speed made good towards your destination drops to around 3 knots.

Ignoring the Current or Wind

Instead of setting a ferry angle across the current or wind, you could just keep the bow of your kayak or canoe pointed towards your destination and adjust your heading to keep pointing at the destination as you paddle forward. You’ll experience leeway movement and your final course will look curved. According to John Winters,

From a pure efficiency standpoint … [this] method works best since you will constantly change course to adjust to conditions and maximize performance. This is good because conditions are always variable. The other positive aspect of paddling towards your destination is that you can ignore minor course variation and focus on the “big picture”. Most people steer too much believing that steering a straight course is best when the more efficient technique is to let the boat wander a bit to suit the vagaries of wind and waves. Few people do this instinctively.

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He later adds,

The reason [that this method is more efficient] is that the boat is traveling more efficiently through the water. Because the boat is traveling faster it has greater course stability and you can more easily adjust for varying conditions. For example, you will need to correct your course less. The other nice thing is that it is a self correcting course and you need not calculate a proper drift angle which, if your crossing is long, could be wrong.

So, Which is the Best Way?

During my experience paddling past the Seven Mile Bridge, my friend Amy and I choose to use ferry angles and a little drift to make our way to an island we were planning to camp on. My friend Dave ignored the current and paddled directly towards the island adjusting his course as needed. All three of us typically paddle at approximately that same speed. The way it worked out was that Amy and I paddled in flat calm water, but Dave was pushed out of the shallows and into an area where the light chop was interacting with the current creating about a foot or so of white-capping chop. Despite the chop and the leeway, Dave beat us to the island. In this instance, his approach worked best for speed.

It’s not always going to be that way, particularly in current, but according to John Winters, the second approach “works best most of the time [in wind] due to the high leeway of shallow boats.”

So, why didn’t the kayaker cross the road? He couldn’t figure out the ferry angle.

6 comments

  • Of course things change when the current or wind is stronger.

    One of many examples that I remember was crossing over to to an island when the current was probably a little over 6 knots.
    Some of the group did the ferry angle thing and others pointed their bow at the destination.

    Those that had a ferry angle easily reached their destination, while those that had their bow pointing at the destination could not overcome the current and were swept behind the island and were only able to meet up because of the lack of current on the lee of the island.

    So when I feel the current will be too strong to overcome, I’ll always have a hard ferry angle until I can determine the required angle and adjust accordingly.

    I suspect you agree and were waiting for a comment like mine:-)

    • I agree with you. With a 6 knot current, another way to beat it is to eddy hop up the shore before making the crossing, hold a lesser angle which will give you more speed made good and then drift back to the island. But, it’s a case by case thing.

  • My experience, if in doubt, with this is to do the ferry glide angle and or the eddy hop early because it is a pay now not pay later approach.Only a weather direction shift will thwart this.
    Paying later[with effort] can mean you don’t have the funds to finish.It can be hard work at the end of the paddle rather than at the beginning! The consequences should be obvious.
    I have a lazy friend who regularly drifts away from me doing the direct line of site course.I always arrive way ahead.He is also a slow learner.I ,also,don’t agree with John Winters.
    For bad conditions I paddle directly into the weather[smallest windage] then bear away when I have paid for my leeway first. Bigger quartering seas are difficult to manage and send you into the troughs.

    • For currents, I use a ferry angle usually, but in wind I often take Winters’ approach depending on the conditions and wind direction. Now and then I’ll vary that approach. One instant that comes to mind was paddling on the south shore of Lake Superior in 6- to 8-foot, NW wind waves and NW wind next to a east-west beach that had sandbars. Without the ferry I was getting pushed over the sandbar, but progress was so so slow at about a mile per hour. Sitting on shore would have been a better choice. In a canoe, I usually take Winters’ approach, because I’ll sit out bigger wave and wind days.

      • I just consider wind as another viscous fluid to contend with.My kayaking is coastal sea with significant tidal flows but also nearly always blowing wind, official average being 15 knots.
        6-8 foot wind waves fetched over a shallow but massive lake would create tricky conditions, being short and steep.
        Sand bars and, for me ,combined with tidal flows are a continual nightmare.All these,together, would need special consideration like staying on the beach.

        • While Lake Superior is deep — up to 1,332 feet with a mean depth of 483 feet — the fresh water typically produces steep waves for the same period and height. The Norwegian settlers on the north shore called the waves square. We often see 6 to 8 second periods and nothing much longer than that.

          In my experience, it seems like Winters’ observation holds up better with wind than current.

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