March 20, 2014

That sinking feeling

A READER in Victoria, British Columbia, asks:  “Have you ever had that unnerving feeling in the pit of your stomach when you’re sailing broadside to the waves at sea?  I mean the feeling of falling, out of control, when you come off the top of a large wave.”
Well, yes, I have. It’s about my least favorite motion aboard a yacht.  The fact is that a boat broadside on to steep seas is probably at greater risk of being capsized when she is on top of a wave than at any other time.

When she is lifted upward and then quickly abandoned by a passing wave, she momentarily experiences a feeling of weightlessness, or at least partial weightlessness. At that moment, with a large area of her hull out of the water, she has practically no form stability.

In theory, a small puff of wind in her sails could blow her over 90 degrees. In practice, the inertia of her mast and rig slows down her response, and before she can heel too much she is once again surrounded by water and experiencing an excess of buoyancy and righting moments by being pressed down into the sea.

Nevertheless, it is a fascinating exercise to sense those moments of instability in your own body when you’re sailing on a beam reach in a lively sea. especially on a light-displacement yacht or racing dinghy.

Today’s Thought
If the danger seems slight, then truly it is not slight.
-- Francis Bacon, De Augmentis Scientiarum: Principiis Obstare

“So how did you kids enjoy Dad’s cooking while I was away?
“We fought over it all the time, Mom.”
“Wow, was it that good?”
“No, the loser had to eat it.”

(Drop by every Monday, Wednesday, Friday for a new Mainly about Boats column.)

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