Vayudoot Aviation

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

+/-2°.

+/-2.5°.

+/-10°.

+/-5°.

2. 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?

274 degrees.

094 degrees.

272 degrees.

294 degress.

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

The range depends on the altitude of the aircraft.

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

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

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

4. 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 ADF and RMI.

Fixed card AF only.

Moving and fixing card ADF.

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

82 m.

8200 m.

8.2 m.

822 m.

6. Night effect in an ADF may cause?

A constant error in the indicated heading.

Fluctuating indications of the needle on the rim.

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

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

7. 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

240

120

60

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

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.

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

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

9. 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?

Neither the VOR nor the NDB needles move.

The VOR needle moves, the ADF needle does not.

The ADF needle moves, the VOR needle does not.

Both VOR and ADF needles move.

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

Precipitation interference.

Coastal effect.

Local thunderstorm activity.

Quadrantal error.

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

Hear the IDENT and must always be switched ON.

Stop loop rotation.

Find the loop 'null' position.

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

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

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

Interference between the ground and space waves.

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

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

13. NDB is the abbreviation for?

Night Directional Beacon.

Non Directional Beacon.

Navigation Direction Beacon.

Non Directional Bearing.

14. 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?

185 degrees relative.

180 degrees relative.

175 degrees relative.

015 degrees relative.

15. 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.

16. What does ADF stand for?

Automatic Direction Finding.

Airport Direction Finding.

Airbone Direction Finding.

Aeroplane Direction Finding.

17. Concerning ADF and NDB?

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

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

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

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

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

Inland 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 right angles.

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

19. 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?

320 degress.

040 degrees.

140 degrees.

220 degrees.

20. 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?

015 degrees relative.

175 degrees relative.

180 degrees relative.

185 degrees relative.

21. 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?

074 degrees.

072 degrees.

254 degrees.

252 degrees.

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

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

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

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

The BFO circuit is activated.

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

8000 m

80 m

8 m

800 m

24. 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?

105 degrees relative.

135 degrees relative.

015 degrees relative.

345 degrees relative.

25. 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 kept 000 degrees.

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 applied wind correction angle.

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

26. ADF is the abbreviation for?

Aircraft Direction Finder.

Automatic Direction Finder.

Aircraft Direction Finding.

Automatic Detection Finder.

27. 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 decreases and the accuracy increases.

The range and the accuracy both decreases.

The range and the accuracy both increases.

The range increases and the accuracy decreases.

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

Frequency drift at the ground station.

Mutual inteference between aircraft aerials.

Interference from other NDBs, particularly during the day.

Interference from other NDBs, particularly at night.

29. 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 (in magnitude and sign) to the applied wind correction angle.

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

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.

30. Allocated frequencies for NDB are?

1900 kHz. to 17500 kHz.

19 Hz to 17500 Hz.

190 kHz to 1750 kHz.

1.90kHz to 17.50 kHz.

31. 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?

135 degrees.

225 degrees.

Impossible to read, due to the RMI failure.

315 degrees.

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

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

The effect of the Aurora Borealis

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

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

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

300-3000 kHz

200-2000kHz

255-455 kHz

200-1750 kHz

34. The ADF indication in the cockpit is a?

Relative bearing on an RMI.

Magnetic bearing on a fixed card indicator.

Relative bearing on a fixed card.

true bearing on an RMI.

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

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

Coastal refraction - lane slip - mountain effect.

Ststic interferemce - statiom interference - latitude error.

Height error - station interference - mountain effect.

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

A beam rotating at 30 Hz.

A cardioid balanced at 30 Hz.

Omnidirectional.

Bi-lobal circular.

37. 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.

254 degrees.

074 degrees.

072 degrees.

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

8000 m.

800 m.

8 m.

80 m.

39. 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?

Eight

Six

Two

Four

40. 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 beacons that is 50 NM inland.

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

Greater from the beacon that is 20 NM inland.

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

41. The quadrantal error of an ADF?

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

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

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

Is caused by interference from sky waves.

42. In order to obtain an ADF bearing the

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

BFO switch must be selected to ;ON;.

sense aerial must be tuned separately.

Mode selector should be switched to 'loop'.

43. 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?

008 degrees.

172 degrees.

352 degrees.

188 degrees.

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

Signal bending caused by electrical interference from aircraft wiring.

Signal bending by the aircraft metallic surfaces.

Skywave/ground wave contamination.

Misalignment of the loop aerial.

45. 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.

315 degrees.

135 degrees.

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

235 degrees.

200 degrees.

020 degrees.

055 degrees.

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