[Paddlewise] objective paddle test

There is a relatively simple way to do objective testing on paddles, in real
conditions in a real kayak.  You need an accurate knot meter on the hull, a
heart meter or (even better) a air uptake meter, and a relatively windless
day.  Then you use either the heart rate monitor, or air uptake meter (this
is a breath mask that measures the total air consumed) at a constant speed.
The paddler must maintain exactly the same speed with the different paddles,
and then he simply records his heart rate, or air consumption.  The less
work it is to maintain the same speed in the same hull, the lower the heart
rate (or air intake).  This would give relative efficiency of course, but
would still yield a valid comparison.  There would be no easy way to make a
tank test yeild these kind of "real world" conditions.

Several things that would be interesting to test this way would be to get a
number of different paddlers, some in good shape, some not, some experienced
paddlers, and some not so experienced, and those familiar with GP and those
that use Euro paddles, male/female, etc., and see what the variations
between them would be.  It might be that the best efficiency with each
paddle comes from using radically different stroke mechanics (this is a
problem that would have to be extensively tested to see if this is
significant, which I suspect it would be).  It also might be that the same
paddle shape and size is not most efficient for everyone.  I would also
suspect that the paddle that is most efficient at a given speed, may not be
the one that is most efficient at another speed.  So you would want to run
the a lot of tests as several speeds to get a complete picture of what is
happening with paddle shape, size, length, etc.  It would interesting to
build a set of "test" paddles that vary only one feature or aspect between
each; for example, make several paddles with exactly the same shape, but
different size.  Or make them exactly the same cross section (foil shape),
and the same area, but with different aspect ratios.

This same test could be used to test hull designs as well (using the same
paddle of course).

I think the real problem with this is to make sure you have a big enough
data base to know what you are actually measuring.  Since so many things
vary between different paddles, and different paddlers, you need a lot of
tests to isolate the important features.  The best stroke mechanics for one
paddle would not be the best for another, which might lead to one to believe
a less than optimum blade shape is better than another if you do not use the
correct stroke mechanics with it.

A simple flow test that I have thought of doing to help visualize the flow
over the blade would be to tape short lengths of bright colored yarn or
string on various places on the blade and go paddling with it.  It would
clearly demonstrate how much cordwise flow (if any) vs. lengthwise flow
occurs over the blade.  You would also get a good idea of when a blade stall
occurs (and would likely quickly learn exactly what a blade stall feels like
at the shaft when it does occurs).

Peter
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