Cruising Tips – Visibility
Signal Advantage (March 2006)
If you have an on-the-water emergency during the day, keep in mind that a mirror is a very effective signaling device. If the weather is clear and there is sunlight, the reflection from a mirror can be seen up to 100 miles away. While it does need sun, a mirror doesnt depend on batteries, satellites, or the electronic watchkeeping of a potential rescuer. Reflecting sunlight into the eyes of a person on another boat or a plane should get his attention. You could heliograph an SOS code, but simply keeping the beam on your target should quickly lead the person at the other end to conclude that the flash he is seeing is not a chance occurrence.
Specialized signal mirrors come with aiming devices, but any handheld mirror will work if you do the following: Hold two fingers in a V at arms length with your target inside it. Now hold the mirror against your cheek just below eye level and adjust the mirror angle so the reflected sunlight shines over your fingers. Turn the mirror so the sunlight plays back and forth across your fingers, and it will also move across the target inside the V. Keep at least two signaling mirrors on board. Put one in your ditch bag and the other on a shelf near the companionway. Don Casey
To Flash or Not (February 2006)
Flashing white lights are far more noticeable than fixed ones and can be much brighter for the same average power drain. However, its dangerous and illegal to show anything that could be confused with a navigation aid, so flashing lights of any color mustnt be used anywhere in coastal waters. The situation on the high seas, where there are no navigation aids, is not as well defined. The International Rules state that the use of flashing lights for drawing attention to a vessel should be avoided. But if a vessel also carries the required lights, and if the flashing light does not interfere with them being seen or with the watchkeepers vision, their use isnt actually prohibited. Unofficially, slow-flashing white strobes are used for various eye-catching purposeson scientific and fishing drift buoys, for example. Masthead strobes are more likely to be noticed than ordinary navigation lights, and at a much greater range, so its understandable that singlehanders sometimes use them on the high seas, in addition to the regulation lights. Aussie Bray
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