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Depth Sounder
The GARMIN digital depth sounder will not give accurate reading beyond 400 feet. In deeper water, the
sensitivity on the unit increases as the transducer tries to get readings back. Consequently, you will receive
many false readings caused by currents, changes in water temperature, fish, and seaweed. Use the depth
sounder only as an aid to navigation in shallow water.
IMPORTANT:
The key to avoiding rocks is NOT the depth sounder – but knowing where you are at all
times
. (Rocks are the greatest navigational and safety hazard in the Islands – but they are all clearly
marked on charts.)
We do not recommend using the depth sounders alarm during the night. It is likely to sound at inappropriate
times such as late at night while fish are passing under the transducer. (Instead consult the onboard tide data,
or the Tides & Currents booklet on board, to determine whether you are anchored in a safe location,
considering how shallow your depth will become when the tide ebbs out of your anchorage in the middle of
the night.)
Remember to
ALWAYS
consult your charts for depth!
Chart Plotter & Radar
We recommend that in addition to using your PRIMARY navigational aids – namely the chart book or the
individual charts – up at the helm while underway, you also utilize the chart plotter for added safety. It helps
you to see if you are where you think you are on the chart book or paper charts. If someone asks “where are
you?” within in a few seconds you need to be able to point to the chart and show them the vessels precise
position. If you can’t you are in danger of hitting a rock.
The only time when the chart plotter becomes your primary navigational tool is when you are in a “tight
spot” like going through a narrow pass or approaching the entrance to a secluded cove. With the chart
plotter, you can zoom-in to make something that is the size of a dime on a paper chart to the size of a
paperback novel or larger. You can see more detail and more importantly any hazards in the area. Your
boats position on the chart plotter is accurate to within 3-meters (about 10-feet).
You should have little need of the radar except for the highly unlikely event that you are suddenly enveloped
by fog, which is rare in this area. The fog typically encountered in this area forms in the wee hours of the
morning and burns off by mid-day. Never depart a safe location into the fog!! To do so, even with radar,
with be contrary to prudent seamanship. FYI, Fog becomes “reduced visibility” when you can see ¼ mile,
about 400 yards, in all directions. It is safe to proceed CAREFULLY in reduced visibility, using your radar
to see beyond the haze, but be sure to look up from the screen about every 10-seconds and use your eyes to
scan the horizon forward, behind and side-to-side. A motor yacht, tanker or freighter traveling at 20-knots
takes only 39-seconds to travel ¼ mile!! You need to see fast moving vessels sooner rather than late so you
can prepare to quickly take evasive action so you can avoid an impending collision.
Note
--
GPS is considered a navigational aid. Do not rely on it. Compasses, charts, and dividers are the
tools to plot position, course, and speed.
VHF Radio
There is one VHF RADIO located on the port side of the helm station. Push and hold the VOL/PWR knob
(bottom right knob on the radio) to turn the radio on and off.
