Guidance Systems

T-45C TS INav-02

Introduction to INav and Voice Procedures

An ILS Critical Area taxiway marking may also

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be present. When ILS is operating, aircraft and

Hold-Short Markings

vehicles may be directed to hold-short at that

line, rather than at the normal hold-short line to

assure noninterference with the ILS beams

Guidance Systems

NOTE: The guidance system of the ILS is made up of

two parts, the localizer transmitter (azimuth information)

and the glideslope transmitter (glidepath information).

Localizer: azimuth beacon transmitter 2.9.4.6.5.1

Provides precise horizontal (course) guidance

information to the runway centerline by way of a

navigational beacon to localizer equipped

aircraft within the sensing area of the localizer

beacon signal

Localizer frequency is identified by international

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Morse code consisting of a four letter identifier

ILS Localizer

with the first letter of the sequence beginning

(Plan View)

with the letter “I” (..)

Transmitter operates on one of 48 channels

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specifically set aside for ILS/LOC

ILS Localizer Beam

Pattern (Plan View)

Frequency range of 108.10 to 111.95 MHz

(lower end of the VOR frequency range)

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Beacon beam is 5 degrees wide as seen on

ILS Localizer Beam

cockpit instruments and is approximately 4

Pattern (Side View)

times as sensitive as conventional VOR or

TACAN NAV signals

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ILS Localizer Beam

Beam is produced by two overlapping modulated

Pattern (10 - 18 nm)

frequencies

(1) Left side of inbound course is a 90 Hz

signal and the right side is a 150 Hz signal

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