Vayudoot Aviation

1. What is the wavelength of an NDB transmitting on 375 kHz?

80 m

8000 m

800 m

8 m

2. What actually happens in the ADF receiver when the BPO position is selected?

The BFO circuit is activated.

The BFO is activated, and the receiver accepts only A1A modulated signals.

The BFO circuit oscillates at an increased frequency in order to allow identification of A2A NDB's.

The BFO circuit imposes a tone onto the carrier wave to make the NDB's ident audible.

3. ADF bearing by an aeroplane by day within the published protection range should be accurate to within a maximum error of

+/-10°.

+/-5°.

+/-2.5°.

+/-2°.

4. Night effect in an ADF may cause?

Noise in the received EM-wave, which hardly will be noticed by the pilots looking at the RMI/

Fluctuating indications of the needle on the rim.

No bearing error because of the built-in compensator unit.

A constant error in the indicated heading.

5. Which statement is correct for tracking towards an NDB in an area with constant wind and constant magnetic variation?

The relative bearing of the NDB should be equal to the QDM.

The relative bearing of the NDB should be equal (in magnitude and sign) to the experienced drift angle.

The relative bearing of the NDB should be equal (in magnitude and sign) to the applied wind correction angle.

The relative bearing of the NDB should be kept 000 degrees.

6. What is the wavelenght of an NDB transmitting on 365 kHz?

82 m.

8200 m.

822 m.

8.2 m.

7. The BFO selector on an ADF receiver is used to

Stop loop rotation.

Hear the IDENT and must always be switched ON.

Find the loop 'null' position.

Hear the IDENT of some NDB stations radiating a continuous wave signal.

8. What is the wavelenght of an NDB transmitting on 375 KHz?

8000 m.

800 m.

8 m.

80 m.

9. Which of the following is likely to have the greatest effect on ADF accuracy?

Frequency drift at the ground station.

Interference from other NDBs, particularly at night.

Interference from other NDBs, particularly during the day.

Mutual interference between aircraft aerials.

10. An aeroplane is tracking away from an NDB maintaining track 120 degrees with 15 degrees starboard (right) drift. The relative bearing indicator (RBI) should indicate a bearing of?

180 degrees relative.

015 degrees relative.

175 degrees relative.

185 degrees relative.

11. A radio beacon has an operational range of 10 NM. By what factor should the transmitter power be increased in order to achieve an operational range of 20 NM?

Two

Four

Eight

Six

12. Errors caused by the effect of coastal refraction on bearings at lower altitudes are maximum when the NDB is

Near the coast and the bearing crosses the coast at an acute angle.

Near the coast and the bearing crosses the coast at right angles.

Inland and the bearing crosses the coast at an acute angle.

Inland and the bearing crosses the coast at right angles.

13. On which of the following displays are you able to get a direct read-out (no calculation is necessary from the pilot) of the magnetic bearing from the aircraft to the NDB?

Moving card ADF and RMI.

Fixed card AF only.

Fixed card ADF and RMI.

Moving and fixing card ADF.

14. Which of the following is the ICAO allocated frequency band for ADF receivers?

200-2000kHz

200-1750 kHz

300-3000 kHz

255-455 kHz

15. In order to obtain an ADF bearing the

Mode selector should be switched to 'loop'.

Signal must be received by both the sense and loop aerials.

sense aerial must be tuned separately.

BFO switch must be selected to ;ON;.

16. Which statement about the errors and effects on NDB radio signal is correct?

Night effect is a result if interference of the surface wave and the space wave causing a reduction is range.

The mountain effect is caused by reflection onto steep slopes of mountainous terrain which may cause big errors in the bearing.

Shore line effects may cause a huge bearing error due to reflection of the radio signals onto steep coasts.

Lighting during atmospheric disturbances may cause a reduction of the signal strength that may result in only slight bearing errors.

17. On the QDR of 075 degrees, (in the vicinity of the station) with magnetic heading of 295 degrees, the relative bearing on the ADF indicator is?

140 degrees.

040 degrees.

320 degress.

220 degrees.

18. An NDB transmits a signal pattern in the horizontal plane which is

A cardioid balanced at 30 Hz.

Bi-lobal circular.

A beam rotating at 30 Hz.

Omnidirectional.

19. Factors liable to affect most NDB/ADF system performance and reliability include

Ststic interferemce - statiom interference - latitude error.

Coastal refraction - lane slip - mountain effect.

Height error - station interference - mountain effect.

Static interference- night effect - absence of failure warning system.

20. An NDB is on a relative bearing of 316 degrees from the aircraft. Given: compass heading 265 degrees. At aircraft deviation = 3W, variation = 36E. At station variation = 34E. Calculate the bearing of the NDB from the aircraft?

072 degrees.

254 degrees.

074 degrees.

252 degrees.

21. What causes the so called "night effect"?

Interference between the ground and space waves.

The absence of the surface wave at distances larger than the skip distance.

The difference in velocity of the EM waves over land over sea at night.

A change in the direction of the plane of the polarisation due to reflection in the ionosphere.

22. Which statement with respect to the range of an range of an NDB?

During the night the range of an NDB will decrease due to the interference of the direct and earth reflected waves.

The range depends on the altitude of the aircraft.

With propagation over sea the range will be greater than range with propagation over land.

In the order to double the range of an NDB, the transmission power should be increased by a factor of 16.

23. A VOR and an NDB are co-located. An aircraft equipped with an RMI is flying away from the beacons on a radial of 090 degrees through an area where magnetic variation is changing rapidly. Which statement is correct?

The VOR needle moves, the ADF needle does not.

Neither the VOR nor the NDB needles move.

Both VOR and ADF needles move.

The ADF needle moves, the VOR needle does not.

24. There are two NDBs, one 20 NM inland, and the other 50 NM inland from the coast. Assuming that the error caused by coastal refraction is the same for both propagations, the extent of the error in a position line plotted by an aircraft that is over water will be?

Greater from the beacon that is 20 NM inland.

Greater from the beacons that is 50 NM inland.

The same from both beacond when the aircraft is on a relative bearing of 180°

The same from both beacons when the aircraft is on a relative bearing of 090° and 270°.

25. The ADF indication in the cockpit is a?

Relative bearing on an RMI.

Relative bearing on a fixed card.

true bearing on an RMI.

Magnetic bearing on a fixed card indicator.

26. You are on a magnetic heading of 055 degrees, and your ADF indicates a relative bearing of 325 degrees. The QDM is?

020 degrees.

055 degrees.

200 degrees.

235 degrees.

27. Quadrantal errors associated with aircraft Automatic Direction Finding (ADF) equipment are caused by

Signal bending by the aircraft metallic surfaces.

Skywave/ground wave contamination.

Signal bending caused by electrical interference from aircraft wiring.

Misalignment of the loop aerial.

28. Concerning ADF and NDB?

ADF is a civilian equipment whereas NDB is a military equipment used by civilian too.

NDB is locator and ADF is an en route nav-aid

NDB is a ground equipment, and ADF is an airborne equipment.

ADF is a ground equipment and NDB can be a ground equipment or an airborne equipment.

29. A VOR and an NDB are co-located. You cross the VOR radial of 240 on a heading of 360 (M). In the vicinity of the station read an ADF bearing of?

300

120

240

60

30. ADF is the abbreviation for?

Aircraft Direction Finder.

Automatic Direction Finder.

Automatic Detection Finder.

Aircraft Direction Finding.

31. If a failed RMI rose is stuck on 090 and the ADF pointer indicates 225, the relative bearing of the station will be?

225 degrees

Impossible to read, due to the RMI failure.

135 degrees.

315 degrees.

32. If a failed RMI rose is stuck on 090 degrees, and the ADF pointer indicates 225 degrees, the relative bearing to the station will be?

315 degrees.

Impossible to read, due to the RMI failure.

225 degrees.

135 degrees.

33. Allocated frequencies for NDB are?

1.90kHz to 17.50 kHz.

19 Hz to 17500 Hz.

190 kHz to 1750 kHz.

1900 kHz. to 17500 kHz.

34. With regard to the range of NDBs and the accuracy of the bearing they provide it can be stated that in general at night?

The range increases and the accuracy decreases.

The range and the accuracy both decreases.

The range and the accuracy both increases.

The range decreases and the accuracy increases.

35. An NDB is on a relative bearing of 316 degrees from an aircraft. Given: compass heading 270. Deviation= 2W/ Variation at the station=28E. calculate the true bearing of the NDB from the aircraft?

252 degrees.

074 degrees.

072 degrees.

254 degrees.

36. The reading of the RMI bearing is 300 degrees. At the tip of the needle. The magnetic variation at the DR position is 24W, The magnetic variation at the NDB is 22W and deviation is -2 degrees. The compass heading is 020 degrees. The true bearing is?

272 degrees.

274 degrees.

094 degrees.

294 degress.

37. What does ADF stand for?

Aeroplane Direction Finding.

Airbone Direction Finding.

Airport Direction Finding.

Automatic Direction Finding.

38. NDB is the abbreviation for?

Night Directional Beacon.

Navigation Direction Beacon.

Non Directional Beacon.

Non Directional Bearing.

39. Given: W/V (T) = 230/20 kts. Variation = 6E. TAS = 80 kts. What relative bearing from an NDB should be maintained in order to achieve an outbound course of 257 (M) from overhead the beacon?

352 degrees.

008 degrees.

172 degrees.

188 degrees.

40. Which of the following is likely to have the greatest effect on ADF accuracy?

Interference from other NDBs, particularly at night.

Mutual inteference between aircraft aerials.

Interference from other NDBs, particularly during the day.

Frequency drift at the ground station.

41. Which one of the following disturbances is most likely to cause the greatest inaccuracy in ADF bearings?

Coastal effect.

Local thunderstorm activity.

Precipitation interference.

Quadrantal error.

42. An aeroplane is tracking away from an NDB maintaining track 020 degrees with 5 degrees starboard (right) drift. The relative bearing indicate (RBI) should indicate a bearing of?

175 degrees relative.

185 degrees relative.

180 degrees relative.

015 degrees relative.

43. The quadrantal error of an ADF?

Is caused by interference from sky waves.

Is caused by aircraft magnetism and varies with the deviation as shown on the deviation table.

May be caused ny interference of VORs within range of the ADF receiver and cannot be compensated for.

Is caused by the refraction from the aircraft's fuselage and is compensated for.

44. An aeroplane is tracking towards an NDB maintaining track 120 degrees with 15 degrees starboard (right) drift. The relative bearing indicator (RBI) should indicate a bearing of?

135 degrees relative.

345 degrees relative.

015 degrees relative.

105 degrees relative.

45. Which statement with respect to the range of an NDB in an area with constant wind and constant magnetic variation?

The relative bearing of the NDB should be equal to the QDM.

The relative bearing of the NDB should be equal (in magnitude and sign) to the experienced drift angle.

The relative bearing of the NDB should be equal (in magnitude and sign) to the applied wind correction angle.

The relative bearing of the NDB should be kept 000 degrees.

46. Night Effect'which causes loss of signal and fading, resulting in bearing errors from NDB transmissions, is due to

static activity increasing at night particularly in the lower frequency band,

The effect of the Aurora Borealis

Skyawave distortion of the null position and is maximum at dawn and dusk.

Interference from other transmissions and is maximum at dusk when east of the NDB

Question Bank

Questions for ADF