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Dealing with engine failures and issues of asymmetrical
thrust are important aspects in the operation of
multiengine seaplanes.
Figure 5-5. Roll instability with a high-mounted engine.
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6-1
LANDING AREA RECONNAISSANCE
AND PLANNING
When a landplane makes an approach at a towered airport,
the pilot can expect that the runway surface will
be flat and free of obstructions. Wind information and
landing direction are provided by the tower. In water
operations, the pilot must make a number of judgments
about the safety and suitability of the landing area,
evaluate the characteristics of the water surface, determine
wind direction and speed, and choose a landing
direction. It is rare for active airport runways to be
used by other vehicles, but common for seaplane pilots
to share their landing areas with boats, ships, swimmers,
jet-skis, wind-surfers, or barges, as well as other
seaplanes.
It is usually a good practice to circle the area of
intended landing and examine it thoroughly for
obstructions such as pilings or floating debris, and to
note the direction of movement of any boats that may
be in or moving toward the intended landing site. Even
if the boats themselves will remain clear of the landing
area, look for wakes that could create hazardous swells
if they move into the touchdown zone. This is also the
time to look for indications of currents in moving
water. Note the position of any buoys marking preferred
channels, hidden dangers, or off-limits areas
such as no-wake zones or swimming beaches. Just as it
is a good idea in a landplane to get a mental picture of
the taxiway arrangement at an unfamiliar airport prior
to landing, the seaplane pilot should plan a taxi route
that will lead safely and efficiently from the intended
touchdown area to the dock or mooring spot. This is
especially important if there is a significant wind that
could make turns difficult while taxiing or necessitate
sailing backward or sideways to the dock. If the water
is clear, and there is not much wind, it is possible to
see areas of waterweeds or obstructions lying below
the surface. Noting their position before landing can
prevent fouling the water rudders with weeds while
taxiing, or puncturing a float on a submerged snag. In
confined areas, it is essential to verify before landing
that there is sufficient room for a safe takeoff under the
conditions that are likely to prevail at the intended
departure time. While obstruction heights are regulated
in the vicinity of land airports and tall structures are
usually well marked, this is not the case with most
water landing areas. Be alert for towers, cranes, powerlines,
and the masts of ships and boats on the approach path.
Finally, plan a safe, conservative path for a go-around
should the landing need to be aborted.
Most established seaplane bases have a windsock, but
if one is not visible, there are many other cues to gauge
the wind direction and speed prior to landing. If there
are no strong tides or water currents, boats lying at
anchor weathervane and automatically point into the
wind. Be aware that some boats also set a stern anchor,
and thus do not move with changes in wind direction.
There is usually a glassy band of calm water on the
upwind shore of a lake. Sea gulls and other waterfowl
usually land into the wind and typically head into the
wind while swimming on the surface. Smoke, flags,
and the set of sails on sailboats also provide the pilot
with a fair approximation of the wind direction. If there
is an appreciable wind velocity, wind streaks parallel to
the wind form on the water. In light winds, they appear
as long, narrow, straight streaks of smooth water
through the wavelets. In winds of approximately 10
knots or more, foam accents the streaks, forming distinct
white lines. Although wind streaks show direction
very accurately, the pilot must still determine which
end of the wind streak is upwind. For example, an eastwest
wind streak could mean a wind from the east or
the west—it is up to the pilot to determine which.
[Figure 6-1]
Figure 6-1. Wind streaks show wind direction accurately, but
the pilot must determine which end of the streak is upwind.
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If there are whitecaps or foam on top of the waves, the
foam appears to move into the wind. This illusion is
caused by the motion of the waves, which move more
quickly than the foam. As the waves pass under the
foam, the foam appears to move in the opposite direction.
　
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