bridges, night passages, and other tricky navigation situations 125
immediately by a separate short (1-second) blast. The tender must reply with
one of two signals:
Bridge will open: one 4- to 6-second blast and a 1-second blast
Bridge cannot open: fi ve short blastsSEA-CRET TIP
X Set your radio to 1 watt when calling a bridge tender. This prevents
the transmission from interfering with others using the same VHF-
FM radio channels.Use the Secret of “Triple Timing” to Verify a Lighted ATON
You’re underway on a wet, windy night, straining through the binoculars to
sight an entrance buoy 4 miles away. Four-foot beam seas cause your 32-foot
cruiser to pitch and roll. You and the crew are tired and just want to get into the
harbor. Th ere it is! You sight an intermittent blip, then another a few seconds
later. Well, not quite the right interval, but it seems close enough—or is it?
In Chapter 1, you learned that lighted aids to navigation have periods of
light and darkness. To time such an aid, use a watch or stopwatch to count
from the fi rst fl ash in the pattern to the fi rst fl ash in the next repetition of the
pattern. For instance, when sighting a buoy that fl ashed every 6 seconds, you
would time from one fl ash to the next. Your watch should read 6 seconds. To
time buoys with groups of fl ashes, you start the watch when you see the fi rst
fl ash of the group and stop it when you again see the fi rst fl ash of the group.
For example, if the listed pattern is Gp Fl (2) 20s, you will expect to measure
an elapsed time of 20 seconds from the start of one pattern repetition to the
start of the next. If the time you measure is 15 seconds, either you’ve measured
wrong or this is not the light you thought it was.
But boats and buoys pitch and roll in heavy weather, making positive
identification tough. Err on the side of safety. Slow down and get closer. Time
light periods three times in a row to verify your landfall or to transit unfamiliar
waters. Follow the steps below for a safe passage in these conditions.
- Raise your height of eye so that you can see the light more consistently
and at a greater distance when a sea is running. - Slow your approach; get closer so that you can see the aid’s distinct
light pattern.