Chapter 3: ILS & VOR Flashcards
what does the ILS ground system consist of?
localiser & glideslope beams
what band and frequency does the localiser transmit on?
VHF band, 108.10 - 111.95 MHz
what is the frequency of the left & right beams for the localiser?
left: 90Hz
right: 150Hz
what band and range does the glideslope transmit on?
UHF band
329.5 - 335.0 MHz
what is the channel spacing for glideslopes?
150 kHz
what are the 2 beams for glideslope and what is their modulated frequency?
upper & lower beam
upper: 90Hz
lower: 150Hz
rate of descent formula
(100 ft/nm (1deg per 100) * groundspeed) / 60
ft/min
what does ILS consist of?
1) receivers
2) control unit
3) ILS indicators
4) aerials
what kinds of receivers are in ILS?
VHF localiser & UHF glideslope receiver
what frequency band does the VHF Omni Range (VOR) operate in?
108 - 118 MHz, channel spacing of 50 kHz
VOR produces how many tracks in how many direction?
infinite number of tracks at 360 degrees (all direction)
the bearing of aircraft depends on?
phase difference between reference and variable phases time difference
frequencies for conventional VOR
30Hz AM (variable phase signal)
9960Hz AM (sub carrier)
information given from carrier wave
1) station identification
2) weather reports
3) aerodome flight information service
VOR equipment consist of?
1) receivers
2) control unit
3) VOR indicators
4) aerials
minimum altitude to receive VOR signal
1000 ft above ground
what does rotating course card do?
calibrated froom 0 - 360 degrees that indicates VOR bearing chosen by pilot
what does OBS knob do?
manually rotate course card
how to read TO-FROM indicator?
triangle points up when flying TO VOR station
trianlge points down when flying FROM VOR station
what does the course deviation indicator do?
indicate direction to turn aircraft to return to course
horizontal dots on OBS means?
each dot represents 2 degree deviation from course
localiser frequency formula
floc = 2f1 - f2
criteria for category 2 instrument landing
1) equipment must be cat. 2 certified
2) RVR = 1200ft
3) abort landing 80ft
localiser degree deviation to output ampere
1deg = 75μAmps
VOR range factors
1) tranmission power
2) station elevation
3) aircraft altitude
ICAO visibility categories
cat 1: 2600ft
cat 2: 1300ft
cat 3: 700ft
