RE: [Paddlewise] Kayak Visibility

>From 30 years of "practical factors" in the Navy (US), I'd like to
suggest two additions to Craig's list factors involved in kayak
visibility.  

It goes without saying that the desired effect is that "the ship" will
image the kayak on its radar and then either avoid it, signal to it or
rescue it, I suppose.  But all the technology in the world will not
enable this outcome if the operator and the radar aren't actively
looking for something that the operator would otherwise consider
clutter, and mask out -- and that can be technological masking or mental
masking.  As Craig mentions, ships are looking for ships, and probably
ships bigger than their ship.  (Or fixed "ships" -- as in the old joke
about the ship's mate who is arguing about right of way with the
operator of Barnegat Light -- an old lighthouse station in New Jersey.)
So the true visibility factor is much more than technical: it's about
priorities, and the ship heading your way is probably more concerned
about maneuvering around Barnegat Light than he is about avoiding your
18 foot kayak -- whether or not he sees it.  Right of way is a relative
term.

That leads to another suggested addition: the ship may paint you on
radar, the captain or crew may see you, but they may not be able to
avoid you.  (See right of way being a relative term, above.)  Therefore,
radar flags or reflectors are nice to have, but they may give an
artificial feeling of safety.  About the only way a kayaker will be
"seen" on radar is with a radar transponder like a RaCon -- usually on
fixed structures or nav aids -- or a SART -- a search and rescue
transponder: these units magnify the return of a radar signal, and
encode data in some cases.  But they are special use devices, with RaCon
inappropriate for our use and SART to be used only in a true emergency.


As Craig indicated, if it hurts when you do "that", don't do "that."

Jack "Joq" Martin


-----Original Message-----
From: Craig Jungers

I guess this would be a good time to talk about the ability of radar to
see (or "paint") a kayak in various conditions and from various vessels.

There are four major factors involved in seeing kayaks from radar
equipped
vessels:

1. Sea state;
2. Radar power, state of tuning, and antenna location and orientation;
3. The "coefficient of reflectivity" of the kayak; and, 4. The attention
factor of the radar observer.

(item 4 was not spotted in a quick moderator review to remove 115 lines of top quoted text)
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