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Seaplane Skiplane Flying Menu > Performance >Takeoff
> Climb and Cruise
When comparing the performance of an airplane
with wheels to the same airplane equipped with floats, the drag
and weight penalty of the floats usually results in a reduced
climb rate for any given weight. Likewise, cruise speeds will
usually be a little lower for a particular power setting. This
in turn means increased fuel consumption and reduced range.
Unless the airplane was originally configured as a seaplane,
the performance and flight planning information for a landplane
converted to floats will typically be found in the Supplements
section rather than the Performance section of the Airplane
Flight Manual (AFM) or Pilot’s Operating Handbook (POH).
In addition to working within the limits of
the seaplane’srange, the pilot planning a cross-country
flight must also consider the relative scarcity of refueling
facilities for seaplanes. Amphibians have access to land airports,
of course, but seaplanes without wheels need to find water landing
facilities that also sell aviation fuel. While planning the
trip, it is wise to call ahead to verify that the facilities
have fuel and will be open at the intended arrival times. The
Seaplane Pilots Association publishes a Water Landing Directory
that is very helpful in planning cross-country flights.
In flight, the seaplane handles very much like
the corresponding landplane. On many floatplanes, the floats
decrease directional stability to some extent. The floats typically
have more vertical surface area ahead of the airplane’s
CG than behind it. If the floats remain aligned with the airflow,
this causes no problems, but if the airplane begins to yaw or
skid, this vertical area acts somewhat like a large control
surface that tends to increase the yaw, making the skid worse.
[Figure 5-2] Additional vertical surface well behind the CG
can counteract the yaw force created by the front of the floats,
so many floatplanes have an auxiliary fin attached to the bottom
of the tail, or small vertical surfaces added to the horizontal
stabilizer. [Figure 5-3]
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