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Instrument Flying Handbook
Airplane Basic Flight Maneuvers Using an Electronic Flight Display
Straight-and-Level flight

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Instrument Flying
Handbook

Preface

Table of Contents

Chapter 1. Human Factors
Chapter 2. Aerodynamic Factors
Chapter 3. Flight Instruments
Chapter 4. Section I
Airplane Attitude Instrument
Flying
Using Analog Instrumentation
Chapter 4. Section II
Airplane Attitude Instrument
Flying
Using an Electronic Flight
Display

Chapter 5. Section I
Airplane Basic
Flight Maneuvers
Using Analog Instrumentation
Chapter 5. Section II
Airplane Basic
Flight Maneuvers
Using an Electronic Flight
Display

Chapter 6. Helicopter
Attitude Instrument Flying

Chapter 7. Navigation Systems
Chapter 8. The National
Airspace System

Chapter 9. The Air Traffic
Control System

Chapter 10. IFR Flight
Chapter 11. Emergency
Operations

One error the instrument pilot encounters is overcontrolling.
Overcontrolling occurs when a deviation of more than
200 fpm is indicated over the optimum rate of change. For
example, an altitude deviation of 200 feet is indicated on the
altimeter, a vertical speed rate of 400 feet should he indicated
on the gauge. if the vertical speed rate showed 600 fpm (200
more than optimum), the pilot would he overcontrolling the
aircraft.

When returning to altitude, the primary pitch instrument
is the VSI tape. If any deviation from the desired vertical
speed is indicated, make the appropriate pitch change using
the attitude indicator

As the aircraft approaches the target altitude, the vertical
speed rate can be slowed in order to capture the altitude in a
more stabilized fashion. Normally within 10 percent of the
rate of climb or descent from the target altitude, begin to
slow the vertical speed rate in order to level off at the target
altitude. This will allow the pilot to level at the desired altitude
without rapid control inputs or experiencing discomfort due
to G-load.

Airspeed Indicator (ASI)
The ASI presents an indirect indication of the pitch attitude.
At a constant power setting and pitch attitude, airspeed
remains constant. As the pitch attitude lowers, airspeed
increases, and the nose should be raised.

As the pitch attitude is increased, the nose of the aircraft will
raise, which will result in au increase in the angle of attack
as well as an increase in induced drag. The increased drag
will begin to slow the momentum of the aircraft, which will
be indicated on the ASI. The airspeed trend indicator will
show a trend as to where the airspeed will be in 6 seconds.
Conversely, if the nose of the aircraft should begin to fall, the
angle of attack as well as induced drag will decrease.

There is a lag associated with the ASI when using it as a pitch
instrument. It is not a lag associated with the construction
of the ASI, hut a lag associated with momentum change.
Depending on the rate of momentum change, the ASI may not
indicate a pitch change in a timely fashion. If the ASI is being
used as the sole reference for pitch change, it may not allow
for a prompt correction. However, if smooth pitch changes
are executed, modem glass panel displays are capable of
indicating 1 knot changes in airspeed and also capable of
projecting airspeed trends.

When flying by reference to flight instruments alone, it
is imperative that all of the flight instruments he cross-
checked for pitch control. By cross-checking all pitch related
instruments, the pilot can better visualize the aircraft attitude
at all times.

As previously stated, the primary instrument for pitch is the
instrument that gives the pilot the most pertinent information
for a specific parameter. When in level flight and maintaining
a constant altitude, what instrument shows a direct indication
of altitude? The only instrument that is capable of showing
altitude is the altimeter. The other instruments are supporting
instruments that are capable of showing a trend away from
altitude, but do not directly indicate an altitude.

The supporting instruments forewarn of an impending
altitude deviation. With an efficient cross-check, a proficient
pilot will be better able to maintain altitude.

Bank Control
This discussion assumes the aircraft is being flown in
coordinated flight which means the longitudinal axis of the
aircraft is aligned with the relative wind, On the PFD, the
attitude indicator shows if the wings are level. The turn rate
indicator, slip/skid indicator, and the heading indicator also
indicate whether or not the aircraft is maintaining a straight
(zero bank) flight path.

Attitude Indicator
The attitude indicator is the only instrument on the PFD that
has the capability of displaying the precise bank angle of the
aircraft. This is made possible by the display of the roll scale
depicted. as part of the attitude indicator.

Figure 5-52 identifies the components that make up the
attitude indicator display. Note that the top of the display
is blue, representing sky, the bottom is brown, depicting
dirt, and the white line separating them is the horizon. The
lines parallel to the horizon line are the pitch scale, which is
marked in 5° increments and labeled every 10°. The pitch
scale always remains parallel to the horizon.

The curved line in the blue area is the roil scale. The triangle
on the top of the scale is the zero index. The hash marks on
the scale represents the degree of bank. [Figure 5-53] The
roll scale always remains in the same position relative to
the horizon line.

 
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