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Full Right Aileron
Elevator Full Up
Full Right Rudder
Full Left Aileron
Elevator Full Up
Full Left Rudder
Full Left Aileron
Elevator Full Up
Reduce Power to Idle
Rudder as Needed
to Maintain Heading
Full Left Rudder, Full Right Aileron,
Elevator Full Up
Figure 4-9. In the plowing position, the exposed area at the
front of the floats, combined with the rearward shift of the
center of buoyancy, can help to counteract the weathervaning
tendency.
Figure 4-10. Plow turn from upwind to downwind.
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4-8
the centrifugal force and allowing the buried float to
come up.
SAILING
Landplane pilots are accustomed to taxiing by pointing
the nose of the airplane in the desired direction and
rolling forward. In seaplane operations, there are often
occasions when it is easier and safer to move the seaplane
backward or to one side because wind, water conditions,
or limited space make it impractical to attempt a turn. If
there is a significant wind, a seaplane can be guided into
a space that might seem extremely cramped to an inexperienced
pilot. Sailing is a method of guiding the seaplane
on the water using the wind as the main motive force. It is
a useful technique for maneuvering in situations where
conventional taxiing is undesirable or impossible. Since
the seaplane automatically aligns itself so the nose points
into the wind, sailing in a seaplane usually means moving
backward.
In light wind conditions with the engine idling or off, a
seaplane naturally weathervanes into the wind. If the
pilot uses the air rudder to swing the tail a few degrees,
the seaplane sails backward in the direction the tail is
pointed. This is due to the keel effect of the floats,
which tends to push the seaplane in the direction the
sterns of the floats are pointing. In this situation, lift the
water rudders, since their action is counter to what is
desired. When sailing like this, the sterns of the floats
have become the front, as far as the water is concerned,
but the rear portions of the floats are smaller and therefore
not as buoyant. If the wind is strong and speed
starts to build up, the sterns of the floats could start to
submerge and dig into the water. Combined with the
lifting force of the wind over the wings, the seaplane
could conceivably flip over backward, so use full forward
elevator to keep the sterns of the floats up and
the seaplane’s nose down. Adding power can also
help keep the floats from submerging.
If enough engine power is used to exactly cancel the
backward motion caused by the wind, the seaplane is
not moving relative to the water, so keel effect disappears.
However, turning the fuselage a few degrees left
or right provides a surface for the wind to push against,
so the wind will drive the seaplane sideways in the
direction the nose is pointed. Combining these techniques,
a skilled pilot can sail a seaplane around obstacles
and into confined docking spaces. [Figure 4-11]
Figure 4-12 shows how to position the controls for the
desired direction of motion in light or strong winds.
With the engine off, lowering the wing flaps and opening
the cabin doors increases the air resistance and
thus adds to the effect of the wind. This increases sailing
speed but may reduce the effect of the air rudder. If
sailing with the engine off results in too much motion
downwind, but an idling engine produces too much
thrust, adding carburetor heat or turning off one magneto
can reduce the engine power slightly. Avoid using
carburetor heat or running on one magneto for
extended periods. Instead, start the engine briefly to
slow down.
Where currents are a factor, such as in strong tidal
flows or a fast flowing river, sailing techniques must
With Left Rudder and Left
Aileron Down, Seaplane
Moves Downwind to the Right
With Rudder and Ailerons
Neutral, Seaplane Moves
Straight Downwind
Engine Thrust to
Balance Wind Motion
With Right Rudder
and Right Aileron
Down, Seaplane
Moves Downwind
to the Left
Water
Rudders Up
Figure 4-11. When the seaplane moves through the water, keel effect drives it in the direction the tail is pointed. With no motion
through the water, the wind pressure on the fuselage pushes the seaplane toward the side the nose is pointed.
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incorporate the movement of the water along with the
wind. The current may be a help or a hindrance, or
change from a help to a hindrance when the pilot
　
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