84 COACHING FUNDAMENTALS
I was working with a student recently who, after some serious commitment to the sport, finally got
planing at full speed. Being the sort of guy that doesn’t want to hold back he also went for a carve gybe
one of his first planing reaches. Sadly I have to report that his parabolic wake soon became a crater…
however, the fact that he was able to foot-steer straight away shows just how easy it is to start carving.
He simply stepped across the board with his back foot and depressed the leeward rail. The board, subject
to a set of physical rules, kindly obliged him by cleanly changing direction downwind…until his style points
dropped a few notches resulting in him being brutally flung into the blue waters of the Ionian Sea...
So what is the relationship between the board and the water every time we turn at planing speed? Let’s look at a
few terms and get an understanding of how things come together to make carves happen.
Circular motion is the movement our carving board makes along its curved path and, as it accelerates radially
inwards, it becomes subject to Newton’s Third Law: for every action there is an equal and opposite reaction.
We looked at this in previous articles as it is everywhere in windsurfing.
To introduce these forces let’s dive into the radical world of bucket swinging! If a person tied a half-filled bucket of
water to a rope and swung the bucket around themselves with enough velocity (definition: the speed of an object
in a particular direction) then the rope would experience tension. This centre-seeking force is called centripetal
force (pronounced Sentry-pEE-tle) and is what keeps the bucket from flying off as it always pulls it towards the
centre. The reaction (or opposite) force to the centripetal force is the (centre-fleeing) centrifugal force. This
represents the object’s inertia and is what forces the water away from the centre of rotation into the bottom of the
bucket to prevent it spilling even though the bucket will be on its side during its aerial circular motion.
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