曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
result in “wheelbarrowing,” and will hinder both
acceleration and overall airplane performance.
INITIAL CLIMB
On short-field takeoffs, the landing gear and flaps
should remain in takeoff position until clear of obstacles
(or as recommended by the manufacturer) and VY
has been established. It is generally unwise for the pilot
to be looking in the cockpit or reaching for landing
gear and flap controls until obstacle clearance is
assured. When the airplane is stabilized at VY, the gear
(if equipped) and then the flaps should be retracted. It
is usually advisable to raise the flaps in increments to
avoid sudden loss of lift and settling of the airplane.
Next, reduce the power to the normal climb setting or
as recommended by the airplane manufacturer.
Common errors in the performance of short-field takeoffs
and maximum performance climbs are:
• Failure to adequately clear the area.
• Failure to utilize all available runway/takeoff
area.
• Failure to have the airplane properly trimmed
prior to takeoff.
• Premature lift-off resulting in high drag.
• Holding the airplane on the ground unnecessarily
with excessive forward-elevator pressure.
• Inadequate rotation resulting in excessive speed
after lift-off.
• Inability to attain/maintain best angle-of-climb
airspeed.
Premature rotation Airplane may lift off
at low airspeed
Airplane may settle
back to the ground
Flight below V
results in shallow
climb
X
Figure 5-8. Effect of premature lift-off.
Ch 05.qxd 5/7/04 7:02 AM Page 5-9
5-10
• Fixation on the airspeed indicator during initial
climb.
• Premature retraction of landing gear and/or wing
flaps.
SOFT/ROUGH-FIELD TAKEOFF
AND CLIMB
Takeoffs and climbs from soft fields require the use of
operational techniques for getting the airplane airborne
as quickly as possible to eliminate the drag caused by
tall grass, soft sand, mud, and snow, and may or may
not require climbing over an obstacle. The technique
makes judicious use of ground effect and requires a
feel for the airplane and fine control touch. These same
techniques are also useful on a rough field where it is
advisable to get the airplane off the ground as soon as
possible to avoid damaging the landing gear.
Soft surfaces or long, wet grass usually reduces the airplane’s
acceleration during the takeoff roll so much
that adequate takeoff speed might not be attained if
normal takeoff techniques were employed.
It should be emphasized that the correct takeoff
procedure for soft fields is quite different from
that appropriate for short fields with firm, smooth
surfaces. To minimize the hazards associated with
takeoffs from soft or rough fields, support of the
airplane’s weight must be transferred as rapidly
as possible from the wheels to the wings as the
takeoff roll proceeds. Establishing and maintaining
a relatively high angle of attack or nose-high
pitch attitude as early as possible does this. Wing
flaps may be lowered prior to starting the takeoff
(if recommended by the manufacturer) to provide
additional lift and to transfer the airplane’s weight
from the wheels to the wings as early as possible.
Stopping on a soft surface, such as mud or snow, might
bog the airplane down; therefore, it should be kept in
continuous motion with sufficient power while lining
up for the takeoff roll.
TAKEOFF ROLL
As the airplane is aligned with the takeoff path, takeoff
power is applied smoothly and as rapidly as the powerplant
will accept it without faltering. As the airplane
accelerates, enough back-elevator pressure should be
applied to establish a positive angle of attack and to
reduce the weight supported by the nosewheel.
When the airplane is held at a nose-high attitude
throughout the takeoff run, the wings will, as speed
increases and lift develops, progressively relieve the
wheels of more and more of the airplane’s weight,
thereby minimizing the drag caused by surface irregularities
or adhesion. If this attitude is accurately maintained,
the airplane will virtually fly itself off the ground,
becoming airborne at airspeed slower than a safe climb
speed because of ground effect. [Figure 5-9]
LIFT-OFF
After becoming airborne, the nose should be lowered
very gently with the wheels clear of the surface to
allow the airplane to accelerate to VY, or VX if obstacles
must be cleared. Extreme care must be exercised
immediately after the airplane becomes airborne and
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
AIRPLANE FLYING HANDBOOK 飞机飞行手册上(60)
