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Instrument Flying Handbook
Airplane Basic Flight Maneuvers Using an Electronic Flight Display

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Instrument Flying


Table of Contents

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

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

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

Horizon line starts moving upward at 27°.
Figure 5-70. Horizon line starts moving upward at 27°. Note that the blue sky remains visible at 17° nose-dawn.

These chevrons are positioned at 50° up on the attitude indicator.
The chevrons appear when the aircraft approaches a nose-high
attitude of 30°. The software automatically de-clutters the PFD
leaving only airspeed, heading, attitude, altimeter, VSI tape,
and the trend vectors. The de-cluttered information reappears
when tile pitch attitude falls below 25°.

For nose-low unusual attitudes, the chevrons are displayed
when the pitch exceeds 15° nose-down. lithe pitch continues
to decrease, the unusual attitude recovery protection de-
clutters the screen at 20° nose-down. The de-cluttered
information reappears when the pitch increases above 15°.

Additionally, there are bank limits that bigger the unusual
attitude protection. if the aircraft's bank increases beyond
60° a continuation of the roll index occurs to indicate the
shortest direction to roll the wings back to level. At 65°, the
PFD de-clutters. All information reappears when the bank
decreases below 60°.

In Figure 5-71, the aircraft has rolled past 60°. Observe the
white line that continues from the end of the bank index.
This line appears to indicate the shortest distance back to
wings level.

When experiencing a failure of the AHRS unit, all unusual
attitude protection is lost. The failure of the AHRS results
in the loss of all heading and attitude indications on the PFD.
In addition, all modes of the autopilot, except for roll and
altitude hold, are lost.

The following picture series represents how important this
technology is in increasing situational awareness, and how
critical it is in improving safety.

Figure 5-72 shows the unusual attitude protection with
valid AHRS and air data computer (ADC) inputs. The
bright red chevrons pointing down to the horizon indicate
a nose-high unusual attitude that can be easily recognized
and corrected.

NOTE: The red chevrons point: back to the level pitch attitude.
The trend indicators show where the airspeed and altitude will
be in 6 seconds. The trend indicator on the heading indicator
shows which direction the aircraft is turning. The slip/skid
indicator clearly shows if the aircraft is coordinated. This
information helps the pilot determine which type of unusual
attitude the aircraft has taken.

Now look at Figure 5-73. The display shows die same
airspeed as the picture above; however, the AHRS unit has
failed. The altimeter and the VSI tape are the only clear
indications that the aircraft is in a nose-high attitude. The
one key instrument that is no longer present is the slip/skid
indicator. There is not a standby turn coordinator installed
in the aircraft for the pilot to reference.

The magnetic compass indicates a heading is being
maintained; however, it is not as useful as a turn coordinator
or slip/skid indicator.