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into the wind until full control deflection is reached.
The point at which the transition from the crab to the
sideslip is made is dependent upon pilot familiarity
with the airplane and experience. With high skill and
experience levels, the transition can be made during
the roundout just before touchdown. With lesser skill
and experience levels, the transition is made at
increasing distances from the runway. Some multiengine
airplanes (as some single-engine airplanes)
have AFM/POH limitations against slips in excess of
a certain time period; 30 seconds, for example. This is
to prevent engine power loss from fuel starvation as
the fuel in the tank of the lowered wing flows towards
the wingtip, away from the fuel pickup point. This
time limit must be observed if the wing-low method
is utilized.
Some multiengine pilots prefer to use differential
power to assist in crosswind landings. The asymmetrical
thrust produces a yawing moment little
different from that produced by the rudder. When
the upwind wing is lowered, power on the upwind
engine is increased to prevent the airplane from
turning. This alternate technique is completely
acceptable, but most pilots feel they can react to
changing wind conditions quicker with rudder and
aileron than throttle movement. This is especially
true with turbocharged engines where the throttle
response may lag momentarily. The differential
power technique should be practiced with an
instructor familiar with it before being attempted
alone.
SHORT-FIELD TAKEOFF AND CLIMB
The short-field takeoff and climb differs from the
normal takeoff and climb in the airspeeds and initial
climb profile. Some AFM/POHs give separate
short-field takeoff procedures and performance
charts that recommend specific flap settings and airspeeds.
Other AFM/POHs do not provide separate
short-field procedures. In the absence of such specific
procedures, the airplane should be operated only as
recommended in the AFM/POH. No operations should
be conducted contrary to the recommendations in the
AFM/POH.
On short-field takeoffs in general, just after rotation
and lift-off, the airplane should be allowed to accelerate
to VX, making the initial climb over obstacles at
VX and transitioning to VY as obstacles are cleared.
[Figure 12-9]
Figure 12-9. Short-field takeoff and climb.
VX
VY
50 ft
Ch 12.qxd 5/7/04 9:54 AM Page 12-16
12-17
When partial flaps are recommended for short-field
takeoffs, many light-twins have a strong tendency to
become airborne prior to VMC plus 5 knots. Attempting
to prevent premature lift-off with forward elevator
pressure results in wheelbarrowing. To prevent this,
allow the airplane to become airborne, but only a few
inches above the runway. The pilot should be prepared
to promptly abort the takeoff and land in the event of
engine failure on takeoff with landing gear and flaps
extended at airspeeds below VX.
Engine failure on takeoff, particularly with obstructions,
is compounded by the low airspeeds and steep
climb attitudes utilized in short-field takeoffs. VX and
VXSE are often perilously close to VMC, leaving scant
margin for error in the event of engine failure as VXSE
is assumed. If flaps were used for takeoff, the engine
failure situation becomes even more critical due to the
additional drag incurred. If VX is less than 5 knots
higher than VMC, give strong consideration to reducing
useful load or using another runway in order to
increase the takeoff margins so that a short-field
technique will not be required.
SHORT-FIELD APPROACH
AND LANDING
The primary elements of a short-field approach and
landing do not differ significantly from a normal
approach and landing. Many manufacturers do not
publish short-field landing techniques or performance
charts in the AFM/POH. In the absence of specific
short-field approach and landing procedures, the
airplane should be operated as recommended in the
AFM/POH. No operations should be conducted
contrary to the AFM/POH recommendations.
The emphasis in a short-field approach is on configuration
(full flaps), a stabilized approach with a constant
angle of descent, and precise airspeed control. As part
of a short-field approach and landing procedure,
some AFM/POHs recommend a slightly slower than
normal approach airspeed. If no such slower speed is
published, use the AFM/POH-recommended normal
approach speed.
Full flaps are used to provide the steepest approach
angle. If obstacles are present, the approach should be
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