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than wheels, even a small amount of drift at touchdown
can create large sideways forces. This is important
because enough side force can lead to capsizing. Also,
the float hardware is primarily designed to take vertical
and fore-and-aft loads rather than side loads.
If the seaplane touches down while drifting sideways,
the sudden resistance as the floats contact the water
creates a skidding force that tends to push the downwind
float deeper into the water. The combination of
the skidding force, wind, and weathervaning as the
seaplane slows down can lead to a loss of directional
control and a waterloop. If the downwind float submerges
and the wingtip contacts the water when the
seaplane is moving at a significant speed, the seaplane
could flip over. [Figure 6-3 on next page]
Floatplanes frequently have less crosswind component
capability than their landplane counterparts.
Directional control can be more difficult on water
because the surface is more yielding, there is less surface
friction than on land, and seaplanes lack brakes.
These factors increase the seaplane’s tendency to
weathervane into the wind.
One technique sometimes used to compensate for
crosswinds during water operations is the same as that
used on land; that is, by lowering the upwind wing
while holding a straight course with rudder. This creates
a slip into the wind to offset the drifting tendency.
The apparent movement of the water’s surface during
the landing approach can be deceiving. Wave motion
may make it appear that the water is moving sideways,
but although the wind moves the waves, the water
itself remains virtually stationary. Waves are simply
an up-and-down motion of the water surface—the
water itself is not moving sideways. To detect side
drift over water and maintain a straight path during
landing, pick a spot on the shore or a stationary buoy
as an aim point. Lower the upwind wing just enough
to stop any drift, and use rudder to maintain a straight
with the sterns of the floats near or touching the water
at the same time. [Figure 6-2] If the nose is much
higher or lower, the excessive water drag puts unnecessary
stress on the floats and struts, and can cause the
nose to pitch down, allowing the bows of the floats to
dig into the water. Touching down on the step keeps
water drag forces to a minimum and allows energy to
dissipate more gradually.
NORMAL LANDING
Make normal landings directly into the wind.
Seaplanes can be landed either power-off or power-on,
but power-on landings are generally preferred because
they give the pilot more positive control of the rate of
sink and the touchdown spot. To touch down at the
slowest possible speed, extend the flaps fully. Use
flaps, throttle, and pitch to control the glidepath and
establish a stabilized approach at the recommended
approach airspeed. The techniques for glidepath control
are similar to those used in a landplane.
As the seaplane approaches the water’s surface,
smoothly raise the nose to the appropriate pitch attitude
for touchdown. As the floats contact the water,
use gentle back pressure on the elevator control to
compensate for any tendency of the nose to drop.
When the seaplane is definitely on the water, close
the throttle and maintain the touchdown attitude until
the seaplane begins to come off the step. Once it
begins to settle into the plowing attitude, apply full
up elevator to keep the nose as high as possible and
minimize spray hitting the propeller.
As the seaplane slows to taxi speed, lower the water
rudders to provide better directional control. Raise the
flaps and perform the after-landing checklist.
The greater the speed difference between the seaplane
and the water, the greater the drag at touchdown, and
the greater the tendency for the nose to pitch down.
This is why the touchdown is made at the lowest possible
speed for the conditions. Many landplane pilots
transitioning to seaplanes are surprised at the shortness
of the landing run, in terms of both time and distance.
It is not uncommon for the landing run from touchdown
to idle taxi to take as little as 5 or 6 seconds.
Sometimes the pilot chooses to remain on the step after
touchdown. To do so, merely add sufficient power and
maintain the planing attitude immediately after touchdown.
It is important to add enough power to prevent
the seaplane from coming off the step, but not so much
that the seaplane is close to flying speed. With too much
taxi speed, a wave or swell could throw the seaplane into
the air without enough speed to make a controlled
　
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