曝光臺 注意防騙 網(wǎng)曝天貓店富美金盛家居專營店坑蒙拐騙欺詐消費者

II-5 ORIGINAL
NAVAIR Ol-Fl4AAD-1
positive dihedral effect (roll caused by sideslip), and
increases the sustained g available. Above 0.7 Mach,
buffet onset occurs prior to the maneuver flap/slat extension
threshold, but once the maneuver flaps/slats are
fully extended, buffet is reduced. Maneuver flaps/slats
will not extend above 0.85 Mach because of the wingsweep
interlocks. Although maneuver flaps/slats increase
the severity of the wing rock between 20 and 28
units AOA, overall departurer esistanceo f the aircraft is
greatly improved (Figure 11-1, sheets I and 2). This
wing rock may bc damped with rudders, but greater
ditliculty may be encounteredw ith maneuverf laps and
slats extended,p articularly at low airspeeds.I f this occurs,
the wing rock may be damped by neutralizing the
lateral and the directional controls and momentarily reducing
AOA to below 20 units. Since maneuver flaps
and slat extension and retmction is fully automatic, no
changes in high-AOA flying techniques are required.
Maneuver flaps/slats should be utilized in the automatic
mode from takeoff to landing.
Maneuvering with inoperativemaneuvering
flaps/slatss hould be approachedw ith
caution ifthe pilot is used to maneuvering
the aircraft with automatic flaps/slats,
since the high-AOA flying qualities will
be degraded from the automatic flap/slat
aircraft. If maneuvering flaps/slats are inoperative,
maintain coordinated flight
with lateral inputs and rudder.
11.6.6 Lateral Control Reversal. Since roll control
is provided by wing mounted spoilers and differential
stabilators, the aircraft exhibits proverse yaw
throughout the flight envelope (yaw in the direction of
the lateral stick input). At high AOAs, several other
aerodynamic and physical properties overpower the proverse
yaw and will yaw and roll the aircraft opposite the
commanded input. The primary contributor to this roll
reversal is the negative directional stability at high
AOAs (above 18 units at 0.9 Mach, and above 2 1 units
at 0.15 Mach). The sequence of events causing this roll
reversal is as follows (for the sake of example consider
a left stick input): 1) The aircrafi initially rolls in the
direction commanded (left); 2) as the aircraft starts to
roll left, airstream’s direction relative to the aircraft
changes Corn the vertical plane (plane ofsymmetry) into
letI sideslip (the definition of kinematic coupling); 3)
because of the negative directional stability, the aircrafi
reacts to the left sideslip by diverging in yaw to the right,
further increasing the left sideslip; 4) because of strong
dihedral effect, the aircraft responds to the left sideslip
and right yaw rate by reversing the roll to a right roll.
‘Ihe net effect in the eyes of the pilot is that at high
angles of attack, the aircraft responds to lateral control
inputs by feinting in the desired direction and then rolling
and yawing opposite to the direction commanded.
For this reason, generous use of the rudders is recommended
at high AOAs in order to roll the aircraft. Roll
SAS on during high-AOA maneuvering will aggravate
the aircraft’s tendency for lateral control reversal and
will result in cross-control inputs during rudder-only
rolls.
11.6.7 Miscellaneous. Speedbrakep osition has no
effect on high-AOA flight characteristics. Wing-sweep
anglesa ft ofthe AUTO scheduler educeb uffet intensity,
but departurer esistancei s reduceda nd more altitude is
required for dive pullout when recovering after a departure.
Therefore, the AUTO sweep schedule is best for
high-AOA maneuvering.
11.6.6 Stall Characteristics. The lg level stall
(maneuverf laps/slats retracted)i s characterizedb y the
onset oflight airframe buffet at 12 to 13 units AOA. This
increases to moderate intensity at 15 units AOA with
essentially no change in intensity at AOA as high as 60”.
Buffet is not a satisfactory cue to determine airspeed or
AOA during high-AOA maneuvering. The reduction in
directional stability is apparent at 20 to 28 units AOA
and even small control inputs will produce mild wing
rock (+lO’ to 15”). Above 25 units AOA, lateral stick
deflectioncauscsroll opposite stickdeflection.The stick
should be centered laterally above 25 units AOA, and
the rudder used to maintain balanced flight. Rudders are
effective at controlling yaw and bank angle at all AOAs.
Large rudder or lateral stick inputs produce an increase
in AOA as sideslip increases.I f the decelerationi s continued
to full aft-stick defiection, AOA is equivalent to
　
中國航空網(wǎng) www.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：F-14D 飛行手冊 Flight Manual 2(61)