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Instrument Flying Handbook
Airplane Basic Flight Maneuvers Using Analog Instrumentation
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

Airspeed Low and Altitude High-Lower Pitch.
Figure 5-20, Airspeed Low and Altitude High-Lower Pitch.

For changes in airspeed in straight-and-level flight, pitch,
bank, and power must be coordinated in order to maintain
constant altitude and heading. When power is changed to
vary airspeed in straight-and-Level flight, a single-engine,
propeller-driven airplane tends to change attitude around all
axes of movement. Therefore, to maintain constant altitude
and heading, apply various control pressures in proportion
to the change in power. When power is added to increase
airspeed, the pitch instruments indicate a climb unless
forward elevator control pressure is applied as the airspeed
changes. With an increase in power, the airplane tends to
yaw and roll to the left unless counteracting aileron and
rudder pressures are applied. Keeping ahead of these changes
requires increasing cross-check speed, which varies with the
type of airplane and its torque characteristics, the extent of
power and speed change involved.

Power Settings
Power control and airspeed changes are much easier when
approximate power settings necessary to maintain various
airspeeds in straight-and-level flight are known in advance.
However, to change airspeed by any appreciable amount, the
common procedure is to underpower or overpower on initial
power changes to accelerate the rate of airspeed change.
(For small speed changes, or in airplanes that decelerate or
accelerate rapidly, overpowering or underpowering is not
necessary.)

Consider the example of an airplane that requires 23"
mercury (Hg) of manifold pressure to maintain a normal
cruising airspeed of 120 knots, and 18" Hg of manifold
pressure to maintain an airspeed of 100 knots. The reduction
in airspeed from 120 knots to 100 knots. while maintaining
straight-and-level flight is discussed below and illustrated in
Figures 5-22, 5-23, and 5-24.

Instrument indications, prior to the power reduction, are
shown in Figure 5-22. The basic attitude is established and
maintained on the attitude indicator. The specific pitch,
bank, and power control requirements are detected on these
primary instruments:

Altimeter—Primary Pitch
Heading indicator—Primary Bank
Airspeed Indicator—Primary Power

Supporting pitch-and-hank instruments are shown in
Figure 5-23. Note that the supporting power instrument is
the manifold pressure gauge (or tachometer if the propeller
is fixed pitch). However, when a smooth power reduction to
approximately 15" Hg (underpower) is made, the manifold
pressure gauge becomes the primary, power instrument.
[Figure 5-23] With practice, power setting can be changed
with only a brief glance at the power instrument, by sensing
the movement of the throttle, the change in sound, and the
changes in the feel of control pressures.

Airspeed and Attitude High-Lower Pitch and Reduce Power.
Figure 5-21, Airspeed and Attitude High-Lower Pitch and Reduce Power.
 
5-9