How Fast is your kayak?

October-November 2001

This is an article from WaveLength Magazine, available in print in North America and globally on the web.
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by Robert Wederich

While shopping for a new kayak, or just viewing new models which appear from year to year, I often wonder about the speed of various boats. Some kayaks look very sleek and fast, but how fast are they?

In reading through kayak reviews, I occasionally encounter reports of their cruising and sprint speeds, in addition to their physical dimensions. Assimilating and analyzing this data has led me to a number of conclusions. It would appear that with few exceptions, just about all kayaks are capable of cruising at a speed of about 3.5 to 4 knots. It is the sprint pace and to a lesser extent, the exercise pace, which really seem to differ based on the varying dimensions of the boats.

Product information and historical sources nearly always contain beam and length metrics, but rarely enough additional information to satisfy the requirements of more sophisticated computer algorithms. For example, Zimmerly (2000) in QAYAQ: Kayaks of Alaska and Siberia, reports beam and length metrics for many native Alaskan and Siberian kayaks. But just how speedy is the 19' 1" one hole Aleut baidarka collected on Akun Island in the Aleutians in 1845 with a 17.1" beam?

At such times I have often wondered if there were some easier way to judge the maximum speed of a given kayak, without having to plug in a lot of numbers into a computer program such as the KAPER or Taylor standard series programs, which require scores of esoteric dimensions in order to estimate foot pounds of force required to propel a specific hull configuration. The personal challenge I decided to accept was to find a way to obtain a good estimate of sprint speed
using a simple method which requires no more than a calculator or paper and pencil.

Knowing that hull speed is related to the width and length of a boat, and running a regression line on this information to forecast the maximum speeds for a number of kayaks with empirical data, I've come up with a simple method. It may not be as accurate as the more sophisticated computer programs, but it can be used by anyone to get an estimate which is definitely in the ball park, i.e., perhaps 90% accurate.

Divide the beam (width) of the kayak in inches by the length in inches, and then extrapolate using the table below.

For greater precision, the regression model is: Maximum speed in kts = 9.15 - 27.71*(W/L).

Applying this formula to the Aleut kayak of 1845, the W/L ratio is .074 which yields a sprint speed above 7 kts. according to the table, or about 7.1 kts. using the formula. Clearly, this narrow 17" native craft was much faster, and far less stable than the average 22"-24" beam touring kayak of today. (One might speculate that the extra speed provided by such a craft was needed to escape a charging Walrus or wounded caribou, or to extend hunting area.)

Applying the regression formula to a few modern kayaks for comparison purposes yields an estimated speed of 7.1 knots for the Blade surf ski. The Blade (w/l = .074) has nearly identical dimensions to the Aleut kayak of 1845, and is a tenth of an inch narrower and one inch shorter than its ancient Aleut cousin, whose design evolved over thousands of years. The Nelo FW 2000 (w/l = .079) hails from a family of lightweight composite racing kayaks with a 17. 4" beam and 18.4' length and compares favorably with the Blade and Aleut, for speed at about 7 kts.

My own touring kayak, a Current Designs Extreme high volume (w/l = .096), with a 21.75" beam and 18.75' length, should top out at about 6.5 kts, while the Valley Anasecuda (w/l = .099) achieves a similar speed of 6.4 kts by creating a narrower 20.5" beam to offset the shorter, more maneuverable 17.2' length.

Not so fast, but far more stable, is the Cabo (w/l = .153) by Ocean Kayak, with a 30" beam and 16.3' length. This craft tops out at about 4.9 kts.

It is important to note that the regression formula was based on limited empirical data obtained for kayaks propelled with a double bladed paddle. The model is not intended to predict the speed of kayaks which are powered in non-traditional manners such as with electric motors, sails, or such new innovations as the pedal driven mechanical penguin wings which power the new Hobie kayaks. The regression model is best used to predict relative sprint speeds of various kayaks, i.e., which boats are faster or slower than others. As paddlers vary in strength and technique, the maximum speed you achieve in any given kayak may be faster or slower than that predicted by the model.

Robert Wederich is employed by the Quantitative Economics and Statistics Group of Ernst & Young LLP, and enjoys kayaking, camping, SCUBA diving and photography with his family when time permits. (Disclaimer: The author performed this study independent of his work with E&Y, and he alone is responsible for the report). Robert.Wederich@ey.com