Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Radio Navigation > NDBs > Flashcards

NDBs Flashcards

1
Q

NDBs use what frequency bands

A

Low and medium frequency bands - 190KHz/1750KHz
Space waves/sky waves and surface waves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Locator Beacon range/use

A

10-25nm
NDB for final approach
Low powered/LF/MF/Two letter ident

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

En route NDB range/use

A

50nm or more
Approach procedures and en route

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Frequency range of NDB

A

190KHz to 1750 KHz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

N0N A1A

A

Unmodulated no modulation no information - N0N

A1A continuous wave - 50nm range - BFO used to ident - breaks it up into chunks

Signal cut therefore no tracking when identifying

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

N0N A2A

A

Modulated continuous wave - no BFO required - amplitude modulated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Cone of confusion

A

Area where ADF needle becomes inaccurate
40 degrees above antenna

Height (nm) x tan (40) x 2 (both sides)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How do you double the range of NDB

A

Power x4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Calculating range overland

A

2 square root of power in watts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Calculating range oversea

A

3 square root of power in watts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Limitations of ADF

A

No indication of failure
Static interference
Mountain effect
Static from CB clouds
Dusk/dawn effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Night Effect

A

Sky waves slow/bend/return signals causing interference from other NDB stations on same frequency

Range increases but accuracy decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Coastal refraction

A

NDB inland to coast become inaccurate when density changes and speeds up over ocean causing bending

Bearing inaccurate NDBs closer to coast less affected as less change in density

Greatest when NDB is inland and at acute angle - Neville when perpendicular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Dip Error

A

Banking moves antenna therefore needle flops towards direction of turn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

ICAO Accuracy requirements

A

+- 6 degrees
+- 5 degrees in UK

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Fading

A

Most common in MF frequency occurs between twilight and night
Weak sky waves return at night due to reduced density in ionosphere and less attenuation

17
Q

How do you find true bearing of the NDB from the aircraft when given relative bearing of NDB to aircraft and compass heading

A

Compass heading + relative bearing
If greater than 360 take away 360 degrees

CDMVT to calculate true bearing to the NDB - use the above as the compass and apply deviation from the ac and variation from the ac to get true heading

18
Q

Wavelength names

A

1-10m = metric
10-100m = decametric
100-1000m = hectometres (NDBs/ADFs)
1000-10,000m = kilometric (NDBs/ADFs)

19
Q

Homing

A

Point at the NDB with relative bearing 0 degrees
Keep the needle on the nose
Wind will blow off track but repoint ac at needle

Used to get TO a NDB

20
Q

Tracking to NDB

A

Choose inbound or outbound course to beacon
Maintained by applying wind correction angle
Used to guide ac to and from NDBs

21
Q

Mountain Effect on NDBs

A

LF/MF radio waves - ground waves - diffraction of waves - scattered

22
Q

Coastal refraction counter measures

A

Use NDBs closer to the coast
Fly at 90 degrees to signal along coast
Fly higher

23
Q

How is a en route NDB identified vs a locator

A

Morse code - 3 letter identifier for en route NDB
Morse code - 2 letter identifier for locators

24
Q

Coastal effect gets worse when

A

Angle of incidence decreases
Maximum from 0 to 30 degrees from the shoreline

25
Q

Why is bearing indicator erratic on N0N/A1A when ident

A

Due to BFO being on to receive on a normal receiver

26
Q

NDB ident (locator vs en route)

A

Morse code signal repeated every 10 seconds

En route = 3 letter identifier
Locator = 2 or 1 letter identifier

27
Q

What is a locator

A

NDB - LF/MF - 190 to 1750KHz

28
Q

Quadrantal Error

A

Wave front from NDB can be distorted by ac structure which approached the aerial

29
Q

Fading is associated

A

Night effect of NDBs

30
Q

ADF needle in a turn will

A

Point slightly in direction of down going wing as becomes out of balance

31
Q

Which frequency band is fading most likely to occur

A

Medium frequency

Radio Navigation (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions