Regal 3300 Owner's Manual page 70

CHAPTER 2
NAVIGATION RULES
An overtaking boat is burdened, and is not the
privileged craft, even though it approaches the
danger zone of the overtaken boat.
The overtaking boat first signals with a single blast
if that boat desires to pass on the starboard side of
the boat ahead, or a double blast if passing to port.
The overtaken craft responds with the same signal if
it is safe, or with the danger signal (5 short blasts or
more) if unsafe. The boat overtaking must not pass
unless the appropriate signals are sounded.
2-6
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