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Instrument Flying Handbook
Airplane Basic Flight Maneuvers Using Analog Instrumentation
Turns

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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

Timed Turns
A timed turn is a turn in which the clock and the turn
coordinator are used to change heading by a specific number
of degrees in a given time, For example, in a standard rate turn
(3° per second), an airplane turns 45° in l5 seconds; in a half
standard rate turn, the airplane turns 45° in 30 seconds.

Prior to performing timed turns, the turn coordinator should
be calibrated to determine the accuracy of its indications.
[Figure 5-34] Establish a standard rate turn as indicated by
the turn coordinator, and as the sweep-second hand of the
clock passes a cardinal point (12, 3, 6, 9), check the heading
on the heading indicator. While holding the indicated rate
of turn constant, note the indicated heading changes at 10
second intervals. If the airplane turns more than or less than
30° in that interval, are respectively larger or small let deflection
of the miniature aircraft of the turn coordinator is necessary
to produce a. standard rate turn. After calibrating the turn
coordinator during turns in each direction, note the corrected
deflections, if any, and apply them during all timed turns.

The same cross-check and control technique is used in making
a timed turn that is used to execute turns to predetermined
headings, except the clock is substituted for the heading
indicator. The miniature aircraft of the turn coordinator is

primary for bank control, the altimeter is primary for pitch
control, and the ASI are primary for power control. Start the
roll-in when the clock's second hand passes a cardinal point,
hold the turn at the calibrated standard rate indication (or
half-standard rate for small heading changes), and begin the
roll-out when the computed number of seconds has elapsed.
If the rates of roll-in and roll-out are the same, the time taken
during entry and recovery does not need to be considered in
the time computation.

Practice timed turns with a full instrument panel and check
the heading indicator for the accuracy of turns. If the turns are
executed without the gyro heading indicator, use the magnetic
compass at the completion of the turn to check turn accuracy,
taking compass deviation errors into consideration.

Compass Turns
In most small airplanes, the magnetic compass is the only
direction-indicating instrument independent of other airplane
instruments and power sources. Because of it's operating
characteristics, called compass errors, pilots are prone to
use it only as a reference for setting the heading indicator,
but knowledge of magnetic compass characteristics permits
full use of the instrument to turn the airplane to correct and
maintain headings.

Turn Coordinator Calibration.
Figure 5-34. Turn Coordinator Calibration.
 
5-21