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what it is doing and how to get it back to straight-and-level
flight as quickly as possible.
Recognizing Unusual Attitudes
As a general rule, any time an instrument rate of movement
or indication other than those associated with the basic
instrument flight maneuvers is noted, assume an unusual
attitude and increase the speed of cross-check to confirm the
attitude, instrument error, or instrument malfunction.
Nose-high attitudes are shown by the rate and direction of
movement of the altimeter needle, vertical speed needle, and
airspeed needle, as well as the immediately recognizable
indication of the attitude indicator (except in extreme
attitudes). [Figure 5-39] Nose-low attitudes are shown
by the same instruments, but in the opposite direction.
[Figure 5-40]
Recovery from Unusual Attitudes
In moderate unusual attitudes, the pilot can normally
reorient by establishing a level flight indication on the
attitude indicator. However, the pilot should not depend on
this instrument if the attitude indicator is the spillable type,
because its upset limits may have been exceeded or it may
have become inoperative due to mechanical malfunction.
If it is the nonspillable-type instrument and is operating
properly, errors up to 5° of pitch-and-bank may result and its
indications are very difficult to interpret in extreme attitudes.
As soon as the unusual attitude is detected, the recommended
recovery procedures stated in the POH/AFM should be
initiated. If there are no recommended procedures stated in
the POH/AFM, the recovery should be initiated by reference
to the ASI, altimeter, VSI, and turn coordinator.
Nose-High Attitudes
If the airspeed is decreasing, or below the desired airspeed,
increase power (as necessary in proportion to the observed
deceleration), apply forward elevator pressure to lower the
nose and prevent a stall, and correct the bank by applying
coordinated aileron and rudder pressure to level the
miniature aircraft and center the ball of the turn coordinator.
The corrective control applications are made almost
simultaneously, but in the sequence given above. A level
pitch attitude is indicated by the reversal and stabilization
5-28
Figure 5-40. Unusual Attitude—Nose-Low.
of the ASI and altimeter needles. Straight coordinated flight
is indicated by the level miniature aircraft and centered ball
of the turn coordinator.
Nose-Low Attitudes
If the airspeed is increasing, or is above the desired airspeed,
reduce power to prevent excessive airspeed and loss of
altitude. Correct the bank attitude with coordinated aileron
and rudder pressure to straight flight by referring to the turn
coordinator. Raise the nose to level flight attitude by applying
smooth back elevator pressure. All components of control
should be changed simultaneously for a smooth, proficient
recovery. However, during initial training a positive,
confident recovery should be made by the numbers, in the
sequence given above. A very important point to remember
is that the instinctive reaction to a nose-down attitude is to
pull back on the elevator control.
After initial control has been applied, continue with a
fast cross-check for possible overcontrolling, since the
necessary initial control pressures may be large. As the rate
of movement of altimeter and ASI needles decreases, the
attitude is approaching level flight. When the needles stop
and reverse direction, the aircraft is passing through level
flight. As the indications of the ASI, altimeter, and turn
coordinator stabilize, incorporate the attitude indicator into
the cross-check.
The attitude indicator and turn coordinator should be checked
to determine bank attitude and then corrective aileron
and rudder pressures should be applied. The ball should
be centered. If it is not, skidding and slipping sensations
can easily aggravate disorientation and retard recovery. If
entering the unusual attitude from an assigned altitude (either
by an instructor or by air traffic control (ATC) if operating
under instrument flight rules (IFR)), return to the original
altitude after stabilizing in straight-and-level flight.
Common Errors in Unusual Attitudes
Common errors associated with unusual attitudes include
the following faults:
1. Failure to keep the airplane properly trimmed. A flight
deck interruption when holding pressures can easily
lead to inadvertent entry into unusual attitudes.
2 Disorganized flight deck. Hunting for charts, logs,
computers, etc., can seriously distract attention from
the instruments.
3. Slow cross-check and fixations. The impulse is to
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Instrument Flying Handbook仪表飞行手册上(94)
