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Frank Reed wrote:

> I was surprised to learn that Robert Gainer passed away some six months ago,
> apparently struck down by a sudden heart attack. Many of you, I am sure,
> remember Robert from his years as an active member of this group. There is a
> fine tribute to him here:

Thank you, a nice gesture. It's a shame I learned more about a list member
whom I enjoyed and respected after he passed than I knew while he was with
us.

For fun exchanges, please see:

http://www.i-DEADLINK-com/lists/navigation/0407/0181.html

You will also see a link to Roberts wit and wisdom that addresses a more
current thread.  That being, why would one need to take multiple sights and
average (by any means)?  The inquiries (as I recall) came from professional
sailors on commercial ships.

My answer would be rather blunt.  A large vessel averages the wave height
for dip plus height of eye for dip correction.  A small vessel attempts to
make the observation at the top of a wave. Given a moments calculations, 6'
off the top of a "real" (not averaged) wave and dip changes by 02!4.

Robert put it in context and much more colorfully.

"Jared said, 
More to the point, wouldn't the difficulty in tracking where you thought the
horizon might be (as you rolled up and down) create more uncertainty in
where the horizon was? Unless the swells were very gentle and the boat a
large ship? "

"I am not quite sure what you are shooting for in this statement. When you
are in the trough of the wave you can�t see anything except the top of the
next wave. You are below sea level by, say maybe 30 feet. At the top of the
wave when you are looking though the scope you can�t see what�s happening
around you, you just line things up as best you can and when you feel the
seat of your pants rise above the cabin top and you get the weightless
feeling you know the boat has started the trip back down and this is the
time to call mark, ready or not. Each time you do this you are reacquiring
the horizon, not tracking it. So if a larger wave then the one you are on is
within, say 2 miles you will �see� that as the horizon. The conditions I use
as an example are from my trip that went into Hurricane Gloria in October of
1976 with 90 knots wind speed. This was with a 31 foot Brit Chance designed
sailboat, the �Chance 30-30�.
All the best, 
Robert Gainer "
  

Bill B.


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