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Pilot's Handbook of Aeronautical Knowledge

Radio Navigation

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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




FROM" is displayed and the course shown is followed, the
aircraft is flown away from the station.

Horizontal Situation Indicator
The HSI is a direction indicator that uses the output
from a flux valve to drive the compass card. The HSI
[Figure 15-30] combines the magnetic compass with
navigation signals and a glideslope. The HSI gives the pilot
an indication of the location of the aircraft with relationship
to the chosen course or radial.

In Figure 15-30, the aircraft magnetic heading displayed
on the compass card under the lubber line is 184°. The
course select pointer shown is set to 295°; the tail of the
pointer indicates the reciprocal, 115°. The course deviation
bar operates with a VOR/Localizer (VOR/LOC) or GPS
navigation receiver to indicate left or right deviations from
the course selected with the course select pointer; operating
in the same manner, the angular movement of a conventional
VOR/LOC needle indicates deviation from course.

Horizontal situation indicator.
Figure 15-30. Horizontal situation indicator.

The desired course is selected by rotating the course select
pointer, in relation to the compass card, by means of the
course select knob. The HSI has a .xed aircraft symbol
and the course deviation bar displays the aircraft's position
relative to the selected course. The TO/FROM indicator is a
triangular pointer. When the indicator points to the head of
the course select pointer, the arrow shows the course selected.
If properly intercepted and .own, the course will take the
aircraft to the chosen facility. When the indicator points to the
tail of the course, the arrow shows that the course selected, if
properly intercepted and .own, will take the aircraft directly
away from the chosen facility.

When the NAV warning flag appears it indicates no reliable
signal is being received. The appearance of the HDG flag
indicates the compass card is not functioning properly.

The glideslope pointer indicates the relation of the aircraft to
the glideslope. When the pointer is below the center position,
the aircraft is above the glideslope and an increased rate
of descent is required. In some installations, the azimuth
card is a remote indicating compass; however, in others the
heading must be checked occasionally against the magnetic
compass and reset.

Radio Magnetic Indicator (RMI)
The RMI [Figure 15-31] is a navigational aid providing
aircraft magnetic or directional gyro heading and very high
frequency omnidirectional range (VOR), GPS, and automatic
direction finder (ADF) bearing information. Remote indicating
compasses were developed to compensate for errors in and
limitations of older types of heading indicators.

Tracking a radial in a crosswind.
Figure 15-32. Tracking a radial in a crosswind.