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Instrument Flying Handbook
Flight Instruments
Flight Support Systems

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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

The computed command indications relieve the pilot of
many of the mental calculations required for instrument
flight. The yellow cue in the ADI [Figure 3-39] provides all
steering commands to the pilot. It is driven by a computer that
receives information from the navigation systems the ADC,
AHRS, and other sources of data. The computer processes this
information, providing the pilot with a single cue to follow.
Following the cue provides the pilot with the necessary three
dimensional flight trajectory to maintain the desired path.
One of the first widely used flight directors was developed
by Sperry and was called the Sperry Three Axis Attitude
Reference System (STARS). Developed in the i960s, it was
commonly found on both commercial and business aircraft
alike. STARS (with a modification) and successive flight
directors were integrated with the autopilots and aircraft
providing a fully integrated flight system.

Typical Cue
Figure 3-39. A Typical Cue That a Pilot Would Follow.

The flight director/autopilot system described below is
typical of installations in many general aviation aircraft.

Typical Flight Director System
Figure 3-40. Components of a Typical Flight Director System.

The components of a typical flight director include the mode
controller, ADI, HSI, and annunciator panel. These units are
illustrated in Figure 3-40.

The pilot may choose From among many modes including
the HDG (heading) mode, the VOR/LOC (localizer tracking)
mode, or the AUTO Approach (APP) or G/S (automatic
capture and tracking of instrument landing system (ILS)
localizer and glide path) mode. The auto mode has a fully
automatic pitch selection computer that takes into account
aircraft performance and wind conditions, and operates once
the pilot has reached the ILS glide slope. More sophisticated
systems allow more flight director modes.

Integrated Flight Control System
The integrated flight control system integrates and merges
various systems into a system operated and controlled by one
principal component. [Figure 3-41] illustrates key components
of the flight control system that was developed from the
onset as a fully integrated system comprised of the airframe,
autopilot, and flight director system. This trend of complete
integration, once seen only in large commercial aircraft, are
now becoming common in the general aviation field.

Autopilot Systems
An autopilot is a mechanical means to control an aircraft
using electrical, hydraulic, or digital systems. Autopilots can
control three axes of the aircraft: roll, pitch, and yaw. Most
autopilots in general aviation control roll and pitch.

Autopilots also function using different methods. The first
is position based. That is, the attitude gyro senses the degree
of difference from a position such as wings level, a change
in pitch, or a heading change.