Results
Q1. Which of the following is likely to have the greatest effect on ADF accuracy?
Interference from other NDBs, particularly at night
Q2. The BFO selector on an ADF receiver is used to:
hear the IDENT of some NDB stations radiating a continuous wave signal
Q3. Some ADFs have a bandwidth control. Consider the following statements:
Broad or wide bandwidth should be selected when listening to music or voice
Q4. An NDB transmits a signal pattern in the horizontal plane which is :
omnidirectional
Q5. Quadrantal errors associated with aircraft Automatic Direction Finding (ADF) equipment are caused by:
signal bending by the aircraft metallic surfaces
Q6. 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
Q7. Which of the following is the ICAO allocated frequency band for ADF receivers?
200-1750 kHz
Q8. Factors liable to affect most NDB/ADF system performance and reliability include:
static interference – night effect – absence of failure warning system
Q9. Consider the following statements on the NDB transmitter:
It is very simple, being required to transmit only a carrier wave and an identification
Q10. Homing on an NDB
Will in most situations result in frequent heading changes when approaching the NDB
Q11. Which one of the following disturbances is most likely to cause the greatest inaccuracy in ADF bearings?
Local thunderstorm activity
Q12. In order to obtain an ADF bearing the:
signal must be received by both the sense and loop aerials
Q13. The heading read on a standard RMI is
The compass heading
Q14. What is the wavelength of an NDB transmitting on 375 kHz?
800 m
Q15. An aircraft is “homing” to a radio beacon whilst maintaining a relative bearing of zero. If the magnetic heading decreases, the aircraft is experiencing:
right drift
Q16. A loop aerial, as used in the ADF, will
Receive a minimum or null signal from a transmitter when the plane of the loop is at right angles to the direction of the transmitter
Q17. Of the bearing indicators available for use on ADFs, the most sophisticated one is
The Radio Magnetic Indicator
Q18. Night Effect’ which causes loss of signal and fading, resulting in bearing errors from NDB transmissions, is due to:
skywave distortion of the null position and is maximum at dawn and dusk
Q19. 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?
Four
Q20. The combination of the polar diagrams of the loop and the sense aerial results in
A cardoid polar diagram, having only one null or minimum
Q21. When using ADF, the sky-wave (night) effect
Is most dominant around dusk and dawn
Q22. Using an ADF indicator of the manually rotateable card type
The card should be rotated so that the aircraft heading is at the top of the indicator
Q23. The basic information given by the ADF is
The relative bearing from the aircraft to the NDB
Q24. Given: Compass heading 270° Deviation 2°W Variation 30°E Relative bearing 316° What is the QDR?
044°
Q25. An RMI indicates aircraft heading. To convert the RMI bearings of NDBs and VORs to true bearings the correct combination for the application of magnetic variation is:
NDB: aircraft position VOR: beacon position
Q26. ADF bearings by an aeroplane by day within the published protection range should be accurate to within a maximum error of:
+/- 5°
Q27. Flying in the vicinity of CB clouds and using ADF
All 3 answers are correct
Q28. 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 50 NM inland
