Sea Kayak Visibility Studied
Contact: Joe Carr at (207) 581-3571.
BAR HARBOR, ME– A sea kayaker a mile out to sea is not clearly visible from
shore. The same principle holds true on the water: if a lobsterman is working traps a mile away from where a kayaker paddles, chances are the
lobsterman will not know the kayaker is there.
Beyond a mile, kayaks are hard to see, regardless of the wave height or
weather conditions.
That was the most definitive result of a recent visibility study conducted
on the Maine coast. Maine sea kayak guides joined with the U.S. Coast Guard and, with support from Maine Sea Grant at the University of Maine, volunteer paddlers, and Coast Guard Auxiliary, tested kayak visibility. They did three trials in different locations under varied weather conditions and tested a dozen homemade and commercially available radar reflectors on three different radar platforms.
The most important discovery was that kayaks one mile from the radar
platform are rarely visible on radar, whether or not they have radar
reflectors. However, results changed under a mile where the presence or
absence of a radar reflector mounted on the kayak or kayaker made a
difference. Considering that a motorboat traveling at 15 knots covers
one-quarter nautical mile in 60 seconds, this may make the difference
between boater safety and an accident.
Results show that radar reflectors need to have lots of angles in order to
reflect radar signals. Typical reflectors have metal plates angled like a
tetrahedral. This is an impractical shape for sea kayakers who are low on
the water and risk injury from sharp objects attached to the boat.
Reflective cloth material built into existing paddling equipment, such as
the paddle float, yielded disappointing results.
According to Paul Travis of the Maine Association of Sea Kayak Guides and
Instructors, “Kayaks by design present a low profile and are generally not
detected reliably on radar. Reflector height is an important factor in
generating quality returns.”
For the kayaker, radar reflectors currently on the market are cumbersome at best, unsafe at their worst. So paddlers need to be creative in devising
ways to be detected. The reflector yielding the best results (at one-eighth
and one-half mile) was a homemade foil hat reflector.
While reflectors help make kayakers more visible on radar within the
less-than-a-mile range, the responsibility for avoiding collision is a
two-way street. Tuning the radar unit is an art in itself and radar, if the
motor vessel has it, is only effective if it is watched.
“In the ocean environment,” stresses Al Johnson, the First Coast Guard
District’s recreational boating specialist, “whether you’re a commercial or
recreational boater or sea kayaker, it is imperative to always know your
location, the status of vessels in your area, and your course of travel.”
For more information about the radar reflector study, visit here.