HOMEWORK
 Read Jeppesen Section 9 B & C
 Gleim chapter 10 (33 questions 10 will be on
your next quiz)
 ASA Chapter 10
 PHAK CHAPTER 15 15-21 TO 15-35
 AIM SECTION 1
ASA
 You should have studied all of the following
questions to date:
– Chapter 1, 2, 3, 4-28 to 4-34, 5-1 to 5-18, 8, 9,
10, 11
Private Pilot Ground School
 Radio Navigation
RADIO NAVIGATION
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VOR ground facilities
Frequencies
Aircraft VOR equipment (OBS, CDI, TO/FM)
Use of equipment
DME
Transponder
ADF
VOR Simulator
 http://www.visi.com/~mim/nav/
The VOR
 What does VOR stand for?
 VHF Omni-directional range
– Omni = means all
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108.0 to 117.95 MHz
Operational for line of sight only
Accuracy to within +/- 1˚
Morse Code is the only way to ID for sure
Test -….- code is for alerting pilots when
maintenance is being done.
 Course or radials referenced to magnetic north
Line-of-sight
Cone of Confusion
 Jepp Page 9-25
 Will have a NAV flag when flying in the cone
of Confusion and when the aircraft is directly
abeam the station.
 Also get a NAV flag anytime the VOR is not
receiving a reliable signal.
VOR/SECTIONAL CHART
The VOR
Sure its cool, but how does it work?
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It radiates 2 signals
1st one is in all directions (Omni-directional)
2nd one is rotated about a point (Directional)
Airplane receives both signals, looks at the
difference between the 2, the result is the radial
360˚ the two signals are in phase
180˚ the two signals are out of phase by ½
270˚ the two signals are out of phase by ¾
Read Jepp page 9-22
The VOR
 Course Roughness
– Irregularities caused by terrain
– RPM settings may cause fluctuations
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The Cone of Confusion
The VOT
VOR Ground Checkpoint
Accuracy of the tests
AFD
Above 1000 ft generally reception
out to 40-45 miles
The VOR High Service Volume
The VOR Low Service Volume
The VOR Terminal Service Volume
VOR INDICATOR with course
deviation indicator CFI
HSI (Horizontal Situation Indicator)
The VOR Head
 The VOR
 OBS Omni-bearing Selector (sometimes
referred to as course selector)
 CDI Course Deviation Indicator
 The scale is 10˚ either side, each dot is 2˚
 Ambiguity Indicator TO/FROM and OFF or
NAV
The VOR
 The white
flag is the
active
indication
for the
ambiguity
indicator
RMI
TRACKING/WIND 15-25
VICTOR AIRWAYS
DME (Distance Measuring
Equipment) pg 9-30
 Freq Range 962 to 1,213 MHz
 Usually co-located with VOR
 Usually freq is paired with VOR so that
when you select VOR freq you get DME freq
automatically.
 DME may exist on its own or with another
nav aid such as ADF but will have a VOR
freq. published for access.
 Required by FARs above 24,000 feet
DME
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DME comes in three yummy flavors:
VOR/DME
VORTAC
TACAN
 Operates in the 960-1215 MHz UHF range,
transmitting in the range of 960-1024 MHz
and 1151-1215 MHz and receiving in the
1025-1150 MHz range
DME
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DME is an active system
There is a transmitter and receiver on both ends
Airborne unit sends signal to ground unit
Ground unit replies
Airborne unit measures the time it takes
12 microseconds = 1 mile for a radio wave
A pair of pulses is sent out specific to that airborne
unit
 Max range is 200 NM
 Slant range (in practical application the DME
readings can be considered accurate if the
airplane is over 5 miles from the station.
DME and ground speed
 If doing an arc around a station GS = 0
 Accurate is going to or from station.
The Transponder
 May be thought of as a microwave
transmitter/receiver.
 The radar antenna is also a
transmitter/receiver
 It will overpower the transponder so
it cycles on and off 800 times a
second with a target 40 miles out
 Primary radar – just picks up
reflected energy
 Secondary radar – picks up
transponders reply
Transponder
 The transponder works like this. The ground
radar equipment sends out a special
interrogation signal asking all aircraft, “Who are
you?”. Only transponder equipped aircraft can
answer. The airborne transponder picks up the
signal and automatically sends back a strong
pulsed signal in reply. The reply signal is
computed into distance and direction (mode c
altitude as well) by the ground station and is
displayed with the aircraft’s target on the
controllers scope.
Transponder
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4096 code capability
1200 VFR
7500 unlawful interference i.e. hijacking
7600 Com failure
7700 Emergency
VFR Flight Following
The ADF/NDB
 MH+RB=MB
 190-415 and 510-535 KHz band
ADF ANTENNAS
 Sense antenna, is a non-directional antenna
that has the capability of providing
directional information. Usually a long wire
installed on the top of the airplane
 Loop antenna, a metal ring enclosing coils
of insulated wires, is usually contained
within a streamlined housing mounted well
forward of the underside of the fuselage.
Senses magnetic bearing from the airplane
to the station.
Switch
 5 positions
 ADF position used for navigation
 REC position or ANT selects only the nondirectional or sense antenna. The loop
antenna and there fore the bearing selector
are disconnected from the system. In this
position operates as a L/MF receiver. Used
for listening only or station identification.
Switch
 EXR = extended range, permitting strong
reception of stations at greater distance.
 BFO = Beat frequency oscillator selection
provides an aural aid to tuning. It should be
used only in tuning unmodulated signals, such
as those broadcast by stations in some foreign
countries. In North America it is not needed
since modulated signals are used. In BFO the
underlying morse code identifier can be heard
through the audio tone of the unmodulated
signal. After the station is tuned and identified,
the function selector shold be repositioned to
ADF
ADF SIMULATOR
 http://www.luizmonteiro.com/Learning_ADF
_Sim.aspx
ADF WITH FIXED CARD
USEABLE RADIUS
NDB SECTIONAL CHARTS
The ADF/NDB
 The ADF is in the airplane
 The NDB is on the ground
 Basically an AM radio station designed for
navigation use.
 If fact you can tune in AM radio stations for.
 NDBs usually operate in the L/MF (low to
medium frequency) of 190 to 535 kHz
The ADF/NDB
 How about that switch with all the funny abbreviations?
 ADF puts the unit in nav mode, uses the loop (gray box)
antenna on the bottom of the aircraft and sense
 ANT puts the unit in receive mode and switches to the big
long antenna that goes from the top of the cabin to the tail.
 BFO puts the unit in Beat Frequency Oscillator. This
selection provides an aural aid to tuning. It should be used
only in tuning unmodulated signals, such is in some foreign
countries. The BFO allows the underlying morse code
identifier to be heard through the audio tone of the
unmodulated signal. After tuned you would turn back to
ADF
 Modulated means to change some characteristic, such as
amplitured, frequency, or phase of an alternating current
wave.
The ADF/NDB
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ADF interpretation
MH + RB = MB to
MH is given info for fixed card
For moveable cards read the heading at the
top
 RB is the bearing measured clockwise from
the nose of the aircraft
 MB is the bearing measured clockwise from
North
ADF TERMS
ADF TRACKING
Moveable
card
ADF/NDB
 The needle points to
the magnetic
bearing to
 To get Relative
Bearing use your
formula
 Figure 1
 MH + RB = MB to
 330 + RB = 210
 RB = 120 (210-330)
 Take 360-120 =240
RB to
 OUR AIRCRAFT
HAVE FIXED
CARDS
Moveable
card
ADF/NDB
 To get Relative
Bearing use your
formula
 Figure 2
 MH + RB = MB to
 315 + RB = 190
 RB = 125 (190315)
 Take 360-125 =235
RB to
Fixed
Card
ADF/NDB
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On these, the needle points to the RB to
For MB use your formula
Figure 4 MH of 320
MH + RB = MB to
320 + 225 = 545-360=185
To get the bearing from don’t forget to add 180
GPS 1-1-19
 There are 24 satellites in the constellation
 They sit at 10,900 miles and orbit in about 12 hours
 There are usually 5 that can be “seen” from anywhere on
earth
 The signals travel at the speed of 186,000 miles per
second
 This requires clocks with accuracy in the billionths of a
second (1 foot equals 1 billionth of a second)
 The receiver calculates a time distance problem to figure
range from a minimum of 4 satellites to determine position.
RNAV
 Stands for Area Navigation
 Basically a VOR/DME computer
 You tell it a radial and a distance and it fixes
a waypoint at that location
 Limitations are you have to be in range of a
VOR/DME at all times
 GPS is replacing this equipment
ILS
 Stands for Instrument Landing System
 Consists of a Localizer, which provides
course guidance and a Glideslope which
provides vertical guidance.
 Very accurate, to within 25 feet at the
threshold
 AIM FIGURE 1-1-9 on page 513
LORAN C AIM 1-1-15
 Stands for Long Range Navigation
 On its way out, but is dying a hard death
 Works on similar principles as GPS only the
stations are ground based
 Additional info “LORAN-C USER
HANDBOOK”
http://www.navcen.uscg.gov/loran/handbook
/h-book.htm
 George is in the LORAN–C West Coast
Chain
ADF SAMPLE QUESITONS
 If the MB TO the station is 040 degrees and
the relative bearing is 270 degrees what is
the MH?
 MH+RB=MB
 MH+270=040
 MH=040-270
 MH=-230 (add 360)
 MH=130
SAMPLE VOR QUESTIONS
 How do you determine which radial you are
on off a VOR?
 DG to compass, tune and identify, rotate
OBS until CDI centers with a From Flag
(radial you are on will be on the top)
 Note: if you centered the CDI with a TO flag
the radial would be read on the bottom of
the VOR or 180 degrees off.
VOR
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You are on the 125 degree radial
You have the following three VOR’s
One set 035 degrees full left CDI To flag
2nd set 215 degrees centered with a TO flag
3rd set 215 degrees NAV flag full scale to
the right
 Which VOR is the VOR that is correct of the
above example
ADF moveable card
 What is the relative bearing if the ADF
moveable card has a HDG of 270 degrees
and a MB TO of 295 degrees
 Draw figure 30 #3
HANDOUTS
 VOR AND ADF EXERCISES