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Pilot's Handbook of Aeronautical Knowledge
Aeronautical Decision-Making

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Pilot's Handbook of Aeronautical Knowledge



Table of Contents

Chapter 1, Introduction To Flying
Chapter 2, Aircraft Structure
Chapter 3, Principles of Flight
Chapter 4, Aerodynamics of Flight
Chapter 5, Flight Controls
Chapter 6, Aircraft Systems
Chapter 7, Flight Instruments
Chapter 8, Flight Manuals and Other Documents
Chapter 9, Weight and Balance
Chapter 10, Aircraft Performance
Chapter 11, Weather Theory
Chapter 12, Aviation Weather Services
Chapter 13, Airport Operation
Chapter 14, Airspace
Chapter 15, Navigation
Chapter 16, Aeromedical Factors
Chapter 17, Aeronautical Decision Making




crews deteriorated due to over-reliance on computers. The
flight crew managers said they worried that pilots would have
less "stick-and-rudder" proficiency when those skills were
needed to manually resume direct control of the aircraft.

A major study was conducted to evaluate the performance
of two groups of pilots. The control group was composed
of pilots who .we an older version of a common twin jet
airliner equipped with analog instrumentation and the
experimental group was composed of pilots who flew the
same aircraft, but newer models equipped with an electronic
flight instrument system (EFIS) and a flight management
system (FMS). The pilots were evaluated in maintaining
aircraft parameters such as heading, altitude, airspeed,
glideslope, and localizer deviations, as well as pilot control
inputs. These were recorded during a variety of normal,
abnormal, and emergency maneuvers during 4 hours of
simulator sessions.

Results of the Study
When pilots who had flown EFIS for several years were
required to .y various maneuvers manually, the aircraft
parameters and flight control inputs clearly showed some
erosion of flying skills. During normal maneuvers such as
turns to headings without a flight director, the EFIS group
exhibited somewhat greater deviations than the analog group.
Most of the time, the deviations were within the practical test
standards (PTS), but the pilots definitely did not keep on the
localizer and glideslope as smoothly as the analog group.
The differences in hand flying skills between the two groups
became more significant during abnormal maneuvers such
as slam-dunks. When given close crossing restrictions, the
analog crews were more adept at the mental math and usually
maneuvered the aircraft in a smoother manner to make the
restriction. On the other hand, the EFIS crews tended to go
"heads down" and tried to solve the crossing restriction on
the FMS. [Figure 17-19]

Another situation used in the simulator experiment reflected
real world changes in approach that are common and can
be assigned on short notice. Once again, the analog crews
transitioned more easily to the parallel runway's localizer,
whereas the EFIS crews had a much more difficult time, with
the pilot going head down for a significant amount of time
trying to program the new approach into the FMS.

While a pilot's lack of familiarity with the EFIS is often
an issue, the approach would have been made easier by
disengaging the automated system and manually flying the
approach. At the time of this study, the general guidelines
in the industry were to let the automated system do as much
of the flying as possible. That view has since changed and
it is recommended that pilots use their best judgment when
choosing which level of automation will most efficiently
do the task considering the workload and situational

Emergency maneuvers clearly broadened the difference in
manual flying skills between the two groups. In general, the
analog pilots tended to fly raw data, so when they were given
an emergency such as an engine failure and were instructed
to fly the maneuver without a flight director, they performed
it expertly. By contrast, SOP for EFIS operations at the time
was to use the flight director. When EFIS crews had their
flight directors disabled, their eye scan again began a more
erratic searching pattern and their manual flying subsequently

Those who reviewed the data saw that the EFIS pilots who
better managed the automation also had better flying skills.
While the data did not reveal whether those skills preceded
or followed automation, it did indicate that automation
management needed to be improved. Recommended "best
practices" and procedures have remedied some of the earlier
problems with automation.

Pilots need to maintain their flight skills and ability to
maneuver aircraft manually within the standards set forth in
the PTS. It is recommended that pilots of automated aircraft
occasionally disengage the automation and manually fly
the aircraft to maintain stick-and-rudder proficiency. It
is imperative pilots understand that the EFD adds to the
overall quality of the flight experience, but it can also lead to
catastrophe if not utilized properly. At no time is the moving
map meant to substitute for a VFR sectional or low altitude
en route chart.