(iv) A vessel engaged in the launching or
recovery of aircraft;
(v) A vessel engaged in mine clearance
operations;
(vi) A vessel engaged in a towing operation
such as severely restricts the
towing vessel and her tow in their
ability to deviate from their course.
visibility The greatest distance at
which one can see and recognize prominent
objects.
W
wake Water surface turbulence left by
a moving boat.
warning In weather advisories, a bulletin
indicating that a hazardous condition,
such as a tornado or flash flood, is in
existence and may threaten some portion
of the warning area.
watch 1. In weather advisories, a bulletin
indicating that a hazardous condition,
such as a tornado or flash flood, may
develop. 2. A period of time during which
a crew member is on duty.
waterline An imaginary line along the
boat hull from the point where the bow
touches the water to the point where the
stern emerges from the water.
wave In water, a series of undulations
that move along the surface.
way Movement of a vessel through
the water, such as headway, sternway, or
leeway.
weather 1. The condition of the atmosphere
at any given time and place. 2. The
windward side.
Western Rivers The Mississippi River,
its tributaries, South Pass, and Southwest
Pass, to the navigational demarcation
lines dividing the Gulf of Mexico
from harbors, rivers and other inland
waters of the United States, and the Port
Allen-Morgan City Alternate Route, and
that part of the Atchafalaya River above
its junction with the Port Allen-Morgan
City Alternate Route including Old River
and the Red River.
wheel A wheel may be used to steer a
boat—usually connected to the rudder
post by means of gears and cables.
whistle Any sound signaling appliance
capable of producing the prescribed
blasts and which complies with the specifications
in Annex III to these Rules.
winch A geared drum turned by a handle
and used to pull lines such as sheets
and halyards.
wind Horizontal motion of the air,
reported in both speed and direction.
Wing-In-Ground (WIG) craft A multimodal
craft which, in its main operational
mode, flies in close proximity to
the surface by utilizing surface-effect
action.
working end The outboard or free end
of a line, chain, or cable, used to make
knots, bends, and splices and to attach to
an anchor, cleat, other vessel.
270 Glossary