Vayudoot Aviation

1. Which one of the following statements applies to the tropopause?

It is, by definition, an isothermal layer

It indicates a strong temperature lapse rate

It separates the troposphere from the stratosphere

It is, by definition, a temperature inversion

2. The thickness of the troposphere varies with

the wind

rotation of the earth

longitude

latitude

3. The 0°C isotherm is forecast to be at FL 50. At what FL would you expect a temperature of -6°C?

FL100

FL110

FL20

FL80

4. The temperature at FL 80 is +6°C. What will the temperature be at FL 130 if the ICAO standard lapse rate is applied?

-6°C

0°C

+2°C

-4°C

5. What is the approximate composition of the dry air by volume in the troposphere?

50 % oxygen, 40 % nitrogen, and the rest other gasses

10 % oxygen, 89 % nitrogen, and the rest other gasses

88 % oxygen, 9 % nitrogen, and the rest other gasses

21 % oxygen, 78 % nitrogen, and the rest other gasses

6. What of the following is the most important constituent in the atmosphere from a weather stand-point?

Water vapour

Nitrogen

Hydrogen

Oxygen

7. If you are flying at FL 300 in an air mass that is 15°C warmer than a standard atmosphere, what is the outside temperature likely to be?

-60°C

-45°C

-30°C

-15°C

8. The height and the temperature of the tropopause are respectively in the order of

8 km and -40°C over the equator

16 km and -75°C over the equator

8 km and - 75°C over the poles

16 km and -40°C over the poles

9. How would you characterise an air temperature of -30°C at the 300 hPa level over Western Europe?

Within +/-5°C of ISA

Low

High

Very low

10. How would you characterise an air temperature of -15°C at the 700 hPa level over Western Europe?

High

20°C below standard

Within +/-5°C of ISA

Low

11. The tropopause is lower

over the North Pole than over the equator

over the equator than over the South Pole

in summer than winter in moderate latitudes

south of the equator than north of it

12. The temperature at FL 110 is -5°C. What will the temperature be at FL 50 if the ICAO standard lapse rate is applied?

+3°C

-3°C

+7°C

0°C

13. Going from the equator to the North Pole, the altitude of the tropopause

increases and its temperature increases

increases and its temperature decreases

decreases and its temperature increases

decreases and its temperature decreases

14. In the mid-latitudes the stratosphere extends on an average from

50 to 85 km

0 to 11 km

85 to more than 200 km

11 to 50 km

15. The troposphere

has a greater vertical extent above the equator than above the poles

is the separation layer between the stratosphere and atmosphere

reaches the same height at all latitudes

contains all oxygen of the stratosphere

16. Which is true of the temperature at the tropopause?

It is highest in middle latitudes

It is higher in polar regions than in equatorial regions

There is no significant difference with change of latitude

It is higher in equatorial regions than in Polar Regions

17. An outside air temperature of -35°C is measured while cruising at FL 200. What is the temperature deviation from the ISA at this level?

5°C warmer than ISA

10°C colder than ISA

10°C warmer than ISA

5°C colder than ISA

18. At a certain position, the temperature on the 300 hPa chart is -48°C; according to the tropopause chart, the tropopause is at FL 330. What is the most likely temperature at FL 350?

-56°C

-54°C

-58°C

-50°C

19. The temperature at FL 140 is -12°C. What will the temperature be at FL 110 if the ICAO standard lapse rate is applied?

-9°C.

-6°C.

-18°C.

-15°C.

20. How would you characterise an air temperature of -55°C at the 200 hPa level over Western Europe?

Within +/-5°C of ISA

High

Very high

Low

21. The rate of decrease of temperature with height per 100 m in the International Standard Atmosphere is

0.65°C

variable

1°C

0.5°C

22. The troposphere is the

part of the atmosphere below the tropopause

boundary between the mesosphere and thermosphere

boundary between the stratosphere and the mesosphere

part of the atmosphere above the stratosphere

23. In the lower part of the stratosphere the temperature

decreases with altitude

is almost constant

increases at first and decreases afterward

increases with altitude

24. How does the height of the tropopause normally vary with latitude in the northern hemisphere?

It decreases from south to north

It remains constant from north to south

It increases from south to north

It remains constant throughout the year

25. If you are flying at FL 120 and the outside temperature is -2°C, at what altitude will the “freezing level” be?

FL 90

FL 130

FL 150

FL 110

26. The average height of the tropopause at 50°N is about

16 km

14 km

8 km

11 km

27. The tropopause is a level at which

temperature ceases to fall with increasing height

pressure remains constant

vertical currents are strongest

water vapour content is greatest

28. What is the vertical temperature lapse rate, up to 11 km, in the ICAO standard atmosphere?

2°C per 1000 m

6.5°C per 1000 m

3°C per 1000 m

4.5°C per 1000 m

29. What is the boundary layer between troposphere and stratosphere called?

Stratosphere

Atmosphere

Tropopause

Ionosphere

30. What is the most likely temperature at the tropical tropopause?

-35°

-25°

-55°

-75°

31. Which statement is correct regarding the International Standard Atmosphere?

At MSL pressure is 1013.25 hPa and the decrease of temperature with height is 1°C per 100m

At MSL temperature is 15°C and the decrease in temperature with height is 1°C per 100m

At MSL temperature is 15°C and pressure is 1013.25hPa

At MSL temperature is 10°C and the decrease in temperature with height is 1°C per 100m

32. What, approximately, is the average height of the tropopause over the equator?

11 km

40 km

16 km

8 km

33. The temperature at 10,000 FT in the International Standard Atmosphere is

-35°C

-20°C

-5°C

0°C

34. Which layer of the atmosphere contains more than 90% of all water vapour?

Upper stratosphere

Ionosphere

Troposphere

Lower stratosphere

35. How does temperature vary with increasing altitude in the ICAO standard atmosphere below the tropopause?

At first it increases and higher up it decreases

Remains constant

Increases

Decreases

36. A temperature of +15°C is recorded at an altitude of 500 metres above sea level. If the vertical temperature gradient is that of a standard atmosphere, what will the temperature be at the summit of a mountain, 2500 metres above sea level?

0°C

+4°C

+2°C

-2°C

37. The lowest assumed temperature in the ICAO Standard Atmosphere is

-100°C

-56.5°C

-44.7°C

-273°C

Question Bank

Questions for ATMOSPHERE 1