NDB

Question 1

BASICS

Answer 1

~ADF
~NDB
~Operates in LF and MF freq bands (190-1750 khz)
~locator beacons have a range of 10-25 nm (used in approach aid)
~normal NDBs have range of 50nm

Question 2

TRANSMISSION AND IDENTIFICATION

Answer 2

~NDB emits an N0N/A1A or N0N/A2A signal
~a beat frequency oscillator is required to be activated to identify an N0N/A1A NDB
~on modern a/c BFO is activated automatically

Question 3

MONITORING AND ACCURACY

Answer 3

~automatic ground monitoring system
~inop NDBs are published via NOTAM
~no on board warning of NDBs failure
~pilots are reuqired to fly +/- 5 degress to be considered estabilished during an approach

Question 4

Cone of confusion

Answer 4

NDB angle is 40 degrees
Use tan to find the radius of the cone

Question 5

INDICATIONS

Answer 5

~fixed card adf
~ moving card adf
These 2 are also called relative bearing indicator RBI

~radio magnetic indicator RMI
~electronic displays (EFIS)

Question 6

Relative bearing

Answer 6

~psotions relative to the nose of the a/c
~magnetic + realative bearing =QDM
APPLY VAR AT THE A/C fro NDBs

Question 7

RANGE

Answer 7

~RANGE OVER LAND NM=2 x sqroot (Tx power in watts)
~RANGE OVER WATER NM= 3 x sqroot (Tx power in watts)

To double the range,power must be quadrupled

Question 8

Errors and accuracy

Answer 8

~max error between 0 and 30 degrees from thecoastal
~erros limited at higher altitude ,when abeam is 90 degress and by placing the ndb further from the coast

Question 9

Night /twlight effect

Answer 9

~The influence of the sky waves and ground waves arriving at the adf with a difference of phase and polarisation
~MF can return as a sky wave at night

Question 10

Mountain effect

Answer 10

~DIFFRACTION of radio waves in mountainous terrain (signal is first bounced into the mountain from the ndb tehn to the a/c)

Question 11

Other erros

Answer 11

~static
~dip bank angle cause dip error