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they are available when needed, they also increase
overall proficiency and add to the enjoyment of
seaplane flying.
NORMAL TAKEOFFS
Make normal takeoffs into the wind. Once the wind
direction is determined and the takeoff path chosen,
configure the seaplane and perform all of the pre-takeoff
checks while taxiing to the takeoff position. Verify
that the takeoff will not interfere with other traffic,
either on the water’s surface or in the air.
Hold the elevator control all the way back and apply full
power smoothly and quickly, maintaining directional
control with the rudder. When the nose reaches its highest
point, ease the back pressure to allow the seaplane to
come up on the step. Establish the optimum planing attitude
and allow the seaplane to accelerate to lift-off speed.
In most cases, the seaplane lifts off as it reaches flying
speed. Occasionally it may be necessary to gently help
the floats unstick by either using some aileron to lift one
float out of the water or by adding a small amount of back
pressure on the elevator control. Once off the water, the
seaplane accelerates more quickly. When a safe airspeed
is achieved, establish the pitch attitude for the best rate of
climb (VY) and complete the climb checklist. Turn as
necessary to avoid overflying noise-sensitive areas, and
reduce power as appropriate to minimize noise.
CROSSWIND TAKEOFFS
In restricted or limited areas such as canals or narrow
rivers, it is not always possible to take off or land
directly into the wind. Therefore, acquiring skill in
crosswind techniques enhances the safety of seaplane
operation. Crosswinds present special difficulties for
seaplane pilots. The same force that acts to lift the
upwind wing also increases weight on the downwind
float, forcing it deeper into the water and increasing
drag on that side. Keep in mind that the allowable
crosswind component for a floatplane may be significantly
less than for the equivalent landplane.
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A crosswind has the same effect on a seaplane during
takeoff as on a landplane, that is, it tends to push the
seaplane sideways across the takeoff path, which
imposes side loads on the landing gear. In addition,
wind pressure on the vertical tail causes the seaplane to
try to weathervane into the wind.
At the beginning of the takeoff roll in a landplane, drift
and weathervaning tendencies are resisted by the friction
of the tires against the runway, usually assisted by
nosewheel steering, or in some cases even differential
braking. The objective in a crosswind takeoff is the
same in landplanes and seaplanes: to counteract drift
and minimize the side loads on the landing gear.
The sideways drifting force, acting through the seaplane’s
center of gravity, is opposed by the resistance of
the water against the side area of the floats. This creates
a force that tends to tip the seaplane sideways, pushing
the downwind float deeper into the water and lifting the
upwind wing. The partly submerged float has even more
resistance to sideways motion, and the upwind wing displays
more vertical surface area to the wind, intensifying
the problem. Without intervention by the pilot, this tipping
could continue until the seaplane capsizes.
During a takeoff in stiff crosswinds, weathervaning
forces can cause an uncontrolled turn to begin. As the
turn develops, the addition of centrifugal force acting
outward from the turn aggravates the problem. The keels
of the floats resist the sideways force, and the upwind
wing tends to lift. If strong enough, the combination of
the wind and centrifugal force may tip the seaplane to
the point where the downwind float submerges and
subsequently the wingtip may strike the water. This is
known as a waterloop, and the dynamics are similar to a
groundloop on land. Although some damage occurs
when the wingtip hits the ground during a groundloop,
the consequences of plunging a wingtip underwater in a
seaplane can be disastrous. In a fully developed waterloop,
the seaplane may be severely damaged or may
capsize. Despite these dire possibilities, crosswind takeoffs
can be accomplished safely by exercising good
judgment and proper piloting technique.
Since there are no clear reference lines for directional
guidance, such as those on airport runways, it can be
difficult to quickly detect side drift on water. Waves
may make it appear that the water is moving sideways,
but remember that although the wind moves the waves,
the water remains nearly stationary. The waves are
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