AIRBORNE WEATHER RADAR

Question 1

1. A frequency used by airborne weather radar is:

Answer 1

9.375 GHz

Question 2

2. An airborne weather radar is required to detect targets up to a maximum range of 200 nm. Ignoring pulse length and flyback in the CRT calculate the maximum PRR.

Answer 2

405 pps

Question 3

3. Using airborne weather radar the weather beam should be used in preference to the fan shaped beam for mapping in excess of ……………. nm:

Answer 3

60 to 70

Question 4

4. Airborne Weather Radar is an example ……………. of radar operating on a frequency of ………….. in the …………… band.

Answer 4

primary, 9375 Mhz SHF

Question 5

5. A prominent island is identified on the 30° right bearing line and the 10 nm range marker of an airborne weather radar. If the heading is 045° (T) and the aircraft is at FL360 what range and bearing should be plotted in order to obtain a fix?

Answer 5

8nm 255° (T)

Question 6

6. The correct sequence of colours of a colour Airborne Weather Radar as returns get stronger is:

Answer 6

green yellow red

Question 7

7. A false indication of water may be given by the AWR display when:

Answer 7

flying over mountainous terrain

Question 8

8. An aircraft heading 017° (T) has a small island showing on the AWR at 45nm range on the 60° left azimuth line. To obtain a fix from this information you should plot:

Answer 8

range 45nm and QTE 137 from the centre of the island

Question 9

9. An aircraft heading 137° (M) has a small island showing on the AWR at 45nm range on the 30° left azimuth line. Local variation is 12° W. To obtain a fix from this information you should plot:

Answer 9

range 45 nm and QTE 275 from the centre of the island

Question 10

10. Airborne weather radar operates on a frequency of:

Answer 10

9375 MHz because it gives the best returns from rainfall associated with Cb

Question 11

11. The mapping mode of Airborne Weather Radar utilises:

Answer 11

a pencil/weather beam from 70 nm to 150 nm

Question 12

12. An Airborne Weather Radar system uses a frequency of 9 GHz because:

Answer 12

the short wavelength allows signals to be reflected from cloud water droplets of all sizes 


Question 13

13. The antenna of an Airborne Weather Radar is stabilised:

Answer 13

in pitch and roll 


Question 14

14. The centre of a small island is identified at the intersection of the 60° left bearing line and 15nm range arc of an airborne weather radar. If the aircraft’s heading and height are 035° (M) and 42,500ft what QTE and range should be plotted in order to obtain a fix from the island? (variation is 20°W)

Answer 14

135 13nm

Question 15

15. The colours used to denote variations in rainfall rate on an Airborne Weather Radar screen are ……….. for very light or no returns, …………… for light returns, ……….. for medium returns and ………… for strong returns.

Answer 15

black green yellow red

Question 16

16. The radar in an aircraft at FL370 detects a cloud at 60 nm. The cloud disappears when the tilt is selected to 2° UP. If the beamwidth of the radar is 6°, at what altitude are the tops of the clouds?

Answer 16

31,000 ft