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Instrument Flying Handbook
Airplane Basic Flight Maneuvers Using an Electronic Flight Display
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
Timed turns to headings are performed in the same fashion
with an EFD as with an analog equipped aircraft. The
instrumentation used to perform this maneuver is the turn rate
indicator as well as the clock. The purpose of this maneuver
is to allow the pilot to gain proficiency in scanning as well
as to further develop the pilot's ability to control the aircraft
without standard instrumentation.

Timed turns become essential when controlling the aircraft
with a loss of the heading indicator. This may become
necessary due to a loss of the AHRS unit or the magnetometer.
In any case, the magnetic compass will still he available. For
navigation. The reason for timed turns in stead of magnetic
compass turns are the simplicity of the maneuver. Magnetic
compass turns require the pilot to take into account various
errors associated with the compass; timed turns do not.

Prior to initiating a turn, determine if the standard rate
indication on the turn rate indicator wilt actually deliver a
3° per second turn. To accomplish this, a calibration must
be made. Establish a turn in either direction at the indicated
standard rate. Start the digital timer as the compass rolls past
a cardinal heading. Stop the timer once the compass card
rolls through another cardinal heading. Roll wings level and
compute the rate of turn. If the turn rate indicator is calibrated
and indicating correctly, 90° of heading change should take
30 seconds. If the time taken to change heading by 90° is
more or less than 30 seconds, then a deflection above or
below the standard rate line needs to he made to compensate
for the difference. Once the calibration has been completed
in one direction, proceed to the opposite direction. When
both directions have been calibrated, apply the calibrated
calculations to all timed turns.

In order to accomplish a timed turn, the amount of heading
change needs to be established. For a change in heading from
120° to a heading of 360°, the pilot calculates the difference
and divides that number by 3. In this case, 120° divided by
30 per second equal 40 seconds. This means that it would
take 40 seconds for an aircraft to change heading 120° if that
aircraft were held in a perfect standard rate turn. Timing for
the maneuver should start as tile aircraft begins rolling into
the standard rate turn. Monitor all flight: instruments during
this maneuver. The primary pitch instrument is the altimeter.
The primary power instrument is the ASI and the primary
bank instrument is the turn rate indicator.

Once the calculated time expires, start a smooth coordinated
roll-out. As long as the pilot utilizes the same rate of roll-in as
roll-out, the time it takes for both will not need to be included
in die calculations. With practice the pilot should level the
wings on the desired heading. If any deviation has occurred,
make small corrections to establish the correct heading.

Compass Turns
The magnetic compass is the only instrument that requires
no other source of power for operation. In the event of an
AHRS or magnetometer failure, the magnetic compass is
the instrument the pilot uses to determine aircraft heading.
For a more detailed explanation on the use of the magnetic
compass, see page 5-21.

Steep Turns
For the purpose of instrument flight training, a steep turn is
defined as any turn in excess of standard rate. A standard rate
turn is defined as 3° per second. The bank angle that equates
to a turn rate of 3° per second varies according to airspeed.
As airspeed increases, the hank angle must be increased.
The exact bank angle that equates to a standard rate turn is
unimportant. Normal standard rate turn bank angles range
from 10° to 20°. The goal of training in steep turn maneuvers
is pilot proficiency in controlling the aircraft with excessive
bank angles.

Training in excessive bank angles will challenge the pilot in
honing cross-checkil1g skills and improve altitude control
throughout a wider range of flight attitudes. Although the
current instrument flight check practical test standards (PTS)
do not call for a demonstration of steep turns on the certification
check flight, this does not eliminate the need for the instrument
pilot-in-training to demonstrate proficiency to an instructor.

Training in steep turns teaches the pilot to recognize and to
adapt to rapidly changing aerodynamic forces that necessitate
an increase in ~ rate of cross-checking all flight instruments.
The procedures for entering, maintaining and exiting a steep
turn are the same as for shallower turns. Proficiency in
instrument cross-check and interpretation is increased due to
the higher aerodynamic forces and increased speed at which
the forces are changing.

 
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