Weather Radar and Met SatellitesAviation Meteorology — DGCA CPL practice questions
Question 1 of 15
PPI scope provides
All 15 questions — Weather Radar and Met Satellites
Aviation Meteorology · DGCA CPL. The correct option is marked on each.
Q1. PPI scope provides
- A.Plan view of echoes — bearing and range✓
- B.Height of echoes
- C.Intensity of echoes
Why: Plan Position Indicator shows a plan view giving bearing and range of echoes.
Q2. RHI scope enables direct reading of
- A.Speed of echoes
- B.Range of echoes
- C.Altitude of CB cells✓
Why: Range Height Indicator gives the height/altitude of cloud cells.
Q3. S band radar is used for
- A.Detection of clouds
- B.Storm detection
- C.Cyclone detection and tracking (rain, precipitation, cyclones)✓
Why: S band penetrates precipitation and is used for cyclone detection and tracking.
Q4. Quantitative Radar measures rate of precipitation using wavelength
- A.5.0 cm
- B.10.0 cm✓
- C.3.2 cm
Why: Quantitative rainfall-rate measurement uses 10 cm to avoid attenuation errors.
Q5. DWR detects if targets are moving towards or away by measuring
- A.Amplitude of return signal
- B.Change of frequency of return signal✓
- C.Time delay of return signal
Why: Doppler radar senses motion via the frequency shift of the return signal.
Q6. Bright Band is an indicator of
- A.Strong/severe storm
- B.CB cloud
- C.Weak storm✓
Why: The bright band marks the melting layer in stratiform precipitation.
Q7. A figure '6' echo is an indication of
- A.Hailstorm
- B.Tornado✓
- C.Severe turbulence
Why: The figure-6 echo is a classic radar signature of a tornado.
Q8. Spiral bands on radar indicate
- A.Severe TS
- B.Tropical Cyclone✓
- C.Hailstorm
Why: Spiral rain bands are the characteristic radar signature of a tropical cyclone.
Q9. On airborne weather radar, Red/Magenta colour indicates
- A.Light precipitation
- B.Moderate precipitation
- C.Heavy precipitation, TS, severe turbulence — AVOID✓
Why: Red/magenta denotes the heaviest returns; areas to be avoided.
Q10. Geostationary satellites are placed at an altitude of approximately
- A.650–1500 km
- B.36,000 km✓
- C.500 km
Why: Geostationary orbit altitude is about 35,800 km.
Q11. How many geostationary satellites are needed to cover the entire globe?
- A.3✓
- B.4
- C.5
Why: Three geostationary satellites spaced 120° apart cover the globe except the poles.
Q12. Kalpana-1 satellite is located at
- A.74°E✓
- B.93.5°E
- C.82°E
Why: Kalpana-1 was stationed at 74°E over the Indian region.
Q13. In IR satellite imagery, the lowest temperatures appear
- A.Black
- B.Dark grey
- C.White (brightest)✓
Why: In IR imagery coldest cloud tops are rendered whitest/brightest.
Q14. Drizzle does not show up on radar because radar returns are proportional to
- A.Square of droplet diameter
- B.Fourth power of droplet diameter
- C.Sixth power of droplet diameter✓
Why: Rayleigh reflectivity varies with the sixth power of drop diameter, so tiny drizzle drops return negligibly.
Q15. INSAT-3D was launched from
- A.Sriharikota
- B.Baikonur
- C.French Guiana Space Centre✓
Why: INSAT-3D was launched on an Ariane-5 from the French Guiana Space Centre, Kourou.