Q1. The ISO-ECHO circuit is incorporated in the AWR:
to display areas of turbulence in cloud
Q2. The ISO-ECHO circuit is incorporated in the AWR:
to display areas of turbulence in cloud
Q3. Airborne weather radar uses a particularly high-frequency radar signal, at 9 to 12 GHz, in order to?
Get good returns from droplets off water and other sorts of precipitation
Q4. In an AWR with a colour CRT, areas of greatest turbulence are indicated by:
most rapid change of colour
Q5. *On the airborne weather radar display in WX mode, different colours are used?
To display different intensity of precipitation
Q6. A false indication of water may be given by the AWR display when:
flying over mountainous terrain
Q7. ## In weather radar the use of cosecant beam in Mapping’ code enables:
Scanning of a large ground zone producing echoes, whose signals are practically independent of distance
Q8. ### To improve the detection of precipitation area(s) in e.g. Thunderstorms, in which the top of the cloud lies at or slightly above the level of flight?
The tilting setting should be lower when the aircraft climbs to a higher altitude
Q9. *While using the AWR in the weather mode, the strongest returns on the screen indicate?
Ares of high concentration of large water droplets
Q10. The cosecant squared beam is used for mapping in the AWR because:
a larger area of ground is illuminated by the beam
Q11. Using airborne weather radar the weather beam should be used in preference to the fan-shaped beam for mapping in excess of………..NM:
60 to 70
Q12. An airborne weather radar is required to detect targets up to a maximum range of 200 NM. Ignoring pulse length and fly back in the CRT calculate the maximum PRR.
405 pps
Q13. In which mode of operation does the aircraft weather radar use a cosecant square radiation pattern?
MAPPING
Q14. * A weather radar, set to the 100 NM scale, shows a squall at 50 NM. By changing the scale to 50 NM, the return on the radar screen should:
Increase in area and move to the top of the screen
Q15. The AWR can be used on the ground provided: (i) the aircraft is clear of personnael , buildings , and vehicles (ii) conical beam is selected (iii) maximum uptilt is selected (iv) the AWR must never be operated on the ground
1, 2 and 3
Q16. In an AWR with a 5° beamwidth, how do you orientate the scanner to receive returns from clouds at or above your level?
2.5° uptilt.
Q17. *An airborne weather radar, with a beamwidth of 5 degrees in azimuth, is being used in the mapping mode. At what maximum range, it will be able to detect and 1 nm wide opening in a sea cliff?
12 nm
Q18. On the AWR display the most severe turbulence will be shown:
by a steep colour gradient
Q19. Before commencing a flight the weather radar should?
Be kept at stand-by until line-up with the runway
Q20. The use of the AWR on the ground is:
permitted provided special precautions are taken to safeguard personnel and equipment.
Q21. #The tilt angle on the AWR at which an active cloud just disappears from the screen is 4 degrees up. If the beam width is 5 degrees and the range to the cloud is 40 nm use the 1 in 60 rule to calculate the approximate height of the cloud relative to the aircraft?
6000 ft above
Q22. *The airborne weather radar (AWR) cannot detect?
Snow
Q23. AWR contour mode is used for?
Identifying areas of maximum turbulence within a cloud
Q24. * In general, the operation of airborne weather radar equipment on the ground is:
Only permitted with certain precautions, to safeguard health of personnel and in protect equipment
Q25. * The pencil-shaped beam of airborne weather radar is used in preference to the mapping mode for the determination of ground features:
Beyond 50 to 60 NM because more power can be concentrated in the narrower beam
Q26. An airborne weather radar unit transmits a 4 degrees beam from a parabolic dish aerial reflector assembly. If the wavelength is 3 cm, the diameter of the dish is?
52.5 cm
Q27. **** Which of the following lists phenomena that CANNOT be detected by weather radar?
Snow; clear air turbulence
Q28. In Airborne Weather Radar (AWR), the main factors which determine whether a cloud will be detected are:
Size of the water drops and the wavelength/frequency used
Q29. *Which of the following cloud types is most readily detected by airborne weather radar when using the ‘weather beam’?
Cumulus
Q30. Airborne weather radar operates on a frequency of:
9 375 MHz because it gives the best returns from rainfall associated with Cb
Q31. When the airborne weather radar is operating in its primary mode, to detect precipitation?
The radar beam is pencil shaped
Q32. Airborne Weather Radars are generally based on the use of?
Primary radar in the SHF band
Q33. *In an Airborne Weather Radar that has a color cathode ray tube (CRT) the areas of greatest turbulence are indicated on the screen by:
Color zones being closest together
Q34. An airborne weather radar is using a 3-degree beam. A cloud is detected at a range of 40 nm. If the scanner is titled up to 3 degrees the cloud disappears. The top of the cloud, in relation to the aeroplane’s cruising level, is approximate?
6000 ft above the level
Q35. The heaviest turbulence is likely to be encountered?
Where the area of heaviest precipitation is closest to the edge of the thunderstorm cell
Q36. In an Airborne Weather Radar, the areas of greatest turbulence are usually indicated on the screen by?
Colour zones or red or magenta
Q37. The cosecant squared beam is used for mapping in the AWR because?
A large area of grounds is illuminated by the beam
Q38. The antenna of an Airborne Weather Radar is stabilized:
in pitch and roll
Q39. ### In order to ascertain whether a cloud return on an Aircraft Weather Radar (AWR) is at or above the height of the aircraft, the tilt control should be set to? (assuming beam width 5 degree)
2.5 degree up
Q40. The airborne weather radar is using a 5-degree beam. The cloud is detected at a range of 60 nm. If the scanner is titled up to 5 degrees, the cloud disappears. Using trigonometry to determine the height of the tops of the cloud, in relation to the aeroplane cruising level, select the nearest answer from the following?
15900 ft above the aircraft
Q41. ** AWR in the…….. Mode progressively………… As distances……….. To equalize screen brightness?
Mapping, decrease power, decreases
Q42. Airborne Weather Radar is an example………..of radar operating on a frequency of…….. in the………band.
primary 9375 MHz SHF
Q43. The stabilization of the weather radar aerial is effective?
For up to $+/-20$ degrees of combined pitch and roll
Q44. The main factors which affect whether an AWR will detect a cloud are:
Correct Answer: the size of the water droplets and the range of the cloud
Wrong Answer: the scanner rotation rate and the frequency/wavelength
Think : In the aircraft we do have option to change the frequency the frequency is already set for the type of radar.
So basically the your AWR will be able to detect the particle or not it will be dependent on size of droplet and range of the cloud.
Q45. Which statements relating to the stabilization system of the airborne weather radar antenna is true?
They are stabilized with respect to the pitch and roll axes but not with respect to the yaw axis
Q46. The mapping mode of Airborne Weather Radar utilizes:
a cosecant²/fan-shaped beam which is effective to 150 NM
Q47. On an AWR colour display, the sequence of colours indicating increasing water droplet size is:
green, yellow, red
Q48. The correct sequence of the colour of a colour Airborne Weather Radar as returns get stronger is:
green, yellow, red
Q49. # On weather radar, the greatest turbulence is likely in an area where targets are?
Show a rapid gradient of change from magenta to yellow
Q50. When using the AWR to detect long-range ground features the most suitable mode of operation or beam selected would be?
The manual mode
Q51. The ISO-ECHO feature of airborne weather radar can be used to detect?
Areas of possible turbulence in cloud
Q52. # Which of the following list of phenomena are least likely to be detected by airborne weather radar?
Clear air turbulence
Q53. The “gain” control knob of an AWR adjusts?
The receiver sensitivity in order to achieve optimum target acquisition
Q54. The theoretical maximum range for an airborne weather radar is determined by the?
Pulse repetition frequency
Q55. An Airborne Weather Radar system uses a frequency of 9 GHz because:
the wavelength is such that reflections are obtained only from the larger water droplets
Q56. A weather radar is used by the pilot to assist in the?
Detection and avoidance of potentially turbulent cloud cells