Chapter 1

Question 1

How is the atmosphere divided in layers?

Answer 1

They are divided according to how the temperature varies with height

Question 1

What is the atmosphere comprised with?

Answer 1

78% nitrogen, 21% oxygen and 1% other gases

Question 2

Are variation of temperature with height constant? Why not?

Answer 2

Some section have distinct lapse rate, these section are what the layers are based on

Question 3

Up to 20km, what are two principle layers?

Answer 3

The lowest is the Troposphere where the temperature decreases with height. Above the tropospheres the stratosphere where temperature is approximately constant with height

Question 4

Does the temperature decrease or increase in troposphere? And the numbers?

Answer 4

It decreases with the height at approximately 2°C/1000 ft or 0.65°/100 m up to tropopause, which has an average of height of 11 km.

Question 5

Which layer contain almost all the water vapour and weather pertinent to aviation?

Answer 5

Troposphere

Question 6

Which layer has the greatest horizontal variation of temperature, density, pressure and stability?

Answer 6

Troposphere

Question 7

Over the poles the cold air causes the tropopause to…?

Answer 7

lower at between FL 250-FL 320 (8-10 km)

Question 8

Over the equator the warm air causes the tropopause to…?

Answer 8

be higher between FL 500-FL 600 (16-18 km)

Question 9

What is the primary reason for rapid changes in the height or disruptions of the tropopause?

Answer 9

This mainly happens between the Hadley, barrel and polar global air circulation cells.

Question 10

What powerful oxidant that that can damage the respiratory system?

Answer 10

Ozone

Question 11

What is ICAO’s ISA stand for? And what does it refer to?

Answer 11

International Standard Atmosphere, and it provides a common reference for temperature, pressure and density. It is a standard against which model, calibrate and compare against the actual atmosphere t any point and time

Question 12

In ISA, how many degrees is the mean sea level (MSL) and how does the air cool down?

Answer 12

MSL is 15°C ,and the air cools at approx. 2°C/1000 ft

Question 13

At 2000 ft, what is the ISA?

Answer 13

11°C

Question 14

If the actual temperature is 6°C, what is the ISA deviation?

Answer 14

ISA -5

Question 15

In ISA condition, what is the MSL pressure?

Answer 15

1013.25 hPa

Question 16

In ISA condition, what is MSL temperature?

Answer 16

15°C

Question 17

In ISA condition, what is the MSL temperature lapse?

Answer 17

0.65°C per 100 m or 1.98°C per 1000 ft up , and up to 11 km where the temperature is -56.5

Question 18

The tropopause and stratospheric inversion are unstable or stable?

Answer 18

Stable