Rime ice forms when large supercooled water drops freeze upon impact with the aircraft.
#2. Advection fog occurs due to ........ air moving over ............ surface over .............
Advection fog forms when warm & moist air moves over a colder surface, cooling it to saturation.
#3. ELR 6.5° C and SALR 7° C on lifting a saturated parcel of air the atmosphere would be
When ELR is less than SALR, the atmosphere is stable.
#4. Gradient wind is weaker than geostrophic wind around a low because
Around a low, the gradient wind is weaker because Coriolis force opposes the centripetal force required for circular motion.
#5. The altimeter of an aircraft is set to QFE before landing, on landing it will indicate
QFE setting zeroes altimeter at airfield elevation, so it reads height above runway.
#6. TAF generally has a validity of .......... hr and TREND ........... hr
TAF typically valid for 24 hours with a trend forecast for the next 9 hours.
#7. CAT is most pronounced on which side of a subtropical jet stream
Clear Air Turbulence is strongest on the cold side of the jet stream core.
#8. Hail forms by collision with super - cooled water drops by
Hail grows when supercooled drops freeze by deposition on ice particles.
#9. Thermal wind blows parallel to ............ keeping ............ to the left
Thermal wind is parallel to isotherms with cold air on the left in the Northern Hemisphere.
#10. Roaring Forties are ............... winds blow throughout the year and are of very stormy nature in
Roaring Forties are strong westerly winds in the Southern Hemisphere between 40°S and 50°S.
#11. Temperature in the troposphere decreases from equator to poles. The thermal wind throughout troposphere is therefore ......... and ........ as height increases
Thermal wind increases with height and blows westerly due to temperature gradient from equator to poles.
#12. A cold front passes a station, the pressure
Pressure initially falls and then rises after the passage of a cold front.
#13. Flying conditions associated with CB during pre monsoon are
CB clouds produce hail, gusts, showers, and severe turbulence in pre-monsoon season.
#14. Which is true of a cold front
Cold fronts have steep slopes, producing heavy convective weather and squall lines.
#15. The observed temperature is - 40 deg C at FL 300 (10 km). it is termed as
ISA temperature at 10 km is -50°C. Observed -40°C is 10°C warmer than ISA.
#16. Aquaplaning may occur in
Aquaplaning occurs on wet runways, often during heavy rain (-GR).
#17. CAT is most likely to be encountered in
Clear Air Turbulence is most pronounced in sharp troughs aloft with strong jet stream winds.
#18. What are Norwesters
Norwesters are severe pre-monsoon thunderstorms over NW India.
#19. Example of non frontal stability is
Inversion is a stable non-frontal atmospheric layer causing non-frontal stability.
#20. If temperature initially is constant and then increases with height, the atmosphere is
Temperature increasing with height (inversion) indicates a stable atmosphere.
#21. Under what conditions severe icing is encountered
Severe icing occurs in supercooled rain below -10°C.
#22. The level from ground to freezing level is more susceptible for icing
Icing is most dangerous from the freezing level up to ~25,000 ft.
#23. Ice accretion
Icing increases drag, weight, and stalling speed, reducing performance.
#24. The wind 260102 KT, is reported in a METAR / SPECI as:
High gust wind (P99) reported in METAR along with normal wind in remarks.
#25. Will SPECI be issued if
SPECI is issued for rapid significant changes, e.g., wind change over thresholds.
#26. CAVOK in a METAR replaces
CAVOK indicates no significant weather or clouds below 5000 ft and good visibility.
#27. The calm and clear night is cooler than cloudy night because
Clouds trap radiation, so clear nights cool faster than cloudy nights.
#28. Diurnal variation of temperature is least
Overcast sky reduces solar heating during day and long-wave cooling at night, minimizing diurnal range.
#29. Density altitude is
Warmer air is less dense, increasing density altitude.
#30. The temperature to which air should be cooled to saturate it is ......... temperature
Dew point is the temperature at which air becomes saturated.
#31. No cyclonic storm or high pressure system form within 5° of the equator because
Coriolis force is too weak near the equator to initiate rotation.
#32. Gradient wind
Gradient wind balances pressure gradient, Coriolis, and centripetal forces around curved isobars.
