VOR

Question 1

Basics

Answer 1

~airborne equipment: antenna,receiver and indicator
~operates in 108.00 -117.975 mhz
~vor freq overlaps with ILS freq which utilises frequncies with and ODD decimal up to 111.95MHz
Ndb uses even decimals

Question 2

Principle of work

Answer 2

phase difference between two transmissions:
~reference phase (RP)
~varaible phase (VP)

Phase angle difference/phase shift»»angular diff between corresponding points of two cycles of equal wavelength,measured in degrees.

On the 090 radial,we could say that the refence phase LEADS the variable phase by 90 degrees

On the 270 radial ,the reference phase LAGS the variable by 90

Question 3

Conventional VOR (CVOR)

Answer 3

~RP:frequency modulated (FM)
~VP: AMPLITUDE MODULATED (AM)
~CLOCKWISE ROTATION

Question 4

DOPPLER VOR (DCOR)

Answer 4

~RP:AMPLITUDE MODULATED (AM)
~VP :FREQUENCY MODULATED (FM)
~ANTICLOCKWISE ROTATION)

Question 5

TYPES OF VOR

Answer 5

~CONVENTIONAL VOR (CVOR):frist gen with roating antenna

~DOPPLER VOR (DVOR) :second gen with fixed antenna which utilises the doppler principle

~EN ROUTE VOR: used by IFR traffic

~Terminal VOR (TVOR); shorter range station used as part of approach and departure procedure at major airports

~TEST VOR (VOT) ;emits a signal to test VOR indicators

Question 6

TRANSMISSION AND IDENTIFICATION

Answer 6

~VORs emit an A9W signal
~vor must be identified before it can be used
~sometimes ATIS info is broadcast on VOR frequencies

Question 7

COVERAGE AND RANGE

Answer 7

range is limited by :
~line of sight (VHF)
~transmitter power

Question 8

Monitoring and accuracy

Answer 8

~automatic ground monitoring sys
~inop VORs are published via NOTAM
~failure of the VOR station&raquo_space;remove of ident ,remove of nav info from the carrier wave,termination of the transmission

~pilots required to fly within half scale defelction +/- 5 to be considered established on a VOR durinf approach

Question 9

Con of confusion

Answer 9

VOR angle is 50 degrees

Question 10

Indications

Answer 10

~radio magnetic indicator (RMI)
~omni bearing indicator (OBI)/course deviation indicator (CDI)
~horizontal situation indicator (HSI)

Question 11

RMI

Answer 11

~works in the same way as NDBs
~head of needle indicates the QDM ,tail QDR

Question 12

OBI/CDI

Answer 12

~position sensing instrumnt,unaware of your heading
~max delfection is 10 degrees
~on a 5 dot display each dot represents 2degree
~TO/FROM FLAGS
~REVERSE SENSING

Question 13

HSI

Answer 13

~Combination of RMI and OBI/CDI
~does not reverse sense

Question 14

Scalloping

Answer 14

Refelctions from terrain can bend radials ,leading to wrong or fluctuating indications ,this is called SCALLOPING