9104. Which of the following is a cause of stratus forming over flat land?
A – Radiation during the night from the earth surface in moderate wind B – Unstable air
C – Convection during the day D – The release of latent heat Ref: AIR: atpl, ir; HELI: all Ans: A
9105. What process in an air mass leads to the creation of wide spread NS, AS and ST cloud coverage?
A – Convection process B – Sinking
C – Lifting D – Radiation
Ref: AIR: atpl, ir; HELI: all Ans: C
9108. What type of cloud is being described? A generally grey cloud layer with fairly uniform base and uniform appearance, which may give drizzle or snow grains.
When the sun is visible through the cloud, the outline is clearly discernible.
Sometimes it appears in the form of ragged patches.
A – Stratus B – Altostratus C – Nimbostratus D – Cirrostratus Ref: all
Ans: A
9109. Which of the following clouds are classified as medium level clouds in temperate regions?
A – C1, CC B – SC, NS C – AS, AC D – CS, ST Ref: all Ans: C
9110. Which of the following types of clouds are evidence of unstable air conditions?
A – ST, CS B – CU, CB C – SC, NS D – C1, SC Ref: all Ans: B
9111. (Refer to figure 050-02)
Which one of the displayed cloud forms is representative of altocumulus castellanus?
A – B B – D C – A D – C Ref: all Ans: D
9139. Which of the following processes within a layer of air may lead to the building of CU and CB clouds?
A – Frontal lifting within stable layers B – Radiation
C – Subsidence D – Convection
Ref: AIR: atpl, ir; HELI: all Ans: D
9142. Which of the following cloud types is a medium level cloud?
A – ST B – CS C – AS D – SC Ref: all Ans: C
9143. A cumulonimbus cloud at mid latitudes in summer contains:
A – only water droplets
B – ice crystals, water droplets and super cooled water droplets C – only ice crystals
D – ice crystals and water droplets but never super cooled water droplets Ref: AIR: atpl, ir; HELI: atpl, ir
Ans: B
9146. Which of the following cloud types is found at high levels?
A – SC B – C1 C – AS D – CU Ref: all Ans: B
9151. Which of the following are medium level clouds?
A – Altostratus and altocumulus B – Cirrocumulus and cirrostratus C – Cumulonimbus
D – All convective clouds Ref: all
Ans: A
9154. A plain in Western Europe with an average height of 500m (1600 ft) above sea level is covered with a uniform SC layer of cloud during the summer months.
At what height above the ground is the base of this cloud to be expected?
A – 7000 – 15000 ft above ground B – 100 – 1500 ft above ground C – 1500 – 7000 ft above ground D – 15000 – 25000 ft above ground Ref: all
Ans: C
9159. What flying conditions may be encountered when flying in cirrus clouds?
A – Average horizontal visibility more than 1000m; light to moderate rime ice B – Average horizontal visibility less than 500m; nil icing
C – Average horizontal visibility less than 500m; light to moderate icing D – Average horizontal visibility more than 1000m; nil icing
Ref: AIR: atpl, ir; HELI: atpl, ir Ans: D
9166. Clouds, classified as being low level are considered to have bases from:
A – 500 to 1000 ft B – 1000 to 2000 ft C – the surface to 6500 ft D – 100 to 200 ft
Ref: all Ans: C
9169. Which of the following types of cloud can extend over the low, medium and high cloud levels?
A – CB B – AC C – ST D – C1
Ref: AIR: atpl, ir; HELI: atpl, ir Ans: A
9171. Altostratus clouds are classified as:
A – convective clouds B – low level clouds C – high level clouds D – medium level clouds Ref: all
Ans: D
9185. Which of the following clouds may extend into more than one layer?
A – Stratus B – Nimbostratus C – Altocumulus D – Cirrus
Ref: AIR: atpl, ir; HELI: atpl, ir Ans: B
9186. Which of the following cloud is classified as low level cloud?
A – ST B – CS C – AS D – CC Ref: all Ans: A
9189. Which types of clouds are typical evidence of stable air conditions?
A – ST, AS B – CU, CB C – NS, CU D – CB, CC
Ref: AIR: atpl, ir; HELI: atpl, ir Ans: A
9191. Fall-streaks or virga are:
A – water or ice particles falling out of a cloud that evaporate before reaching the ground
B – strong down draughts in the polar jet stream, associated with jet streaks C – gusts associated with a well developed Bora
D – strong katabatic winds in mountainous areas and accompanied by heavy precipitation
Ref: AIR: atpl, ir; HELI: atpl, ir Ans: A
9193. Convective clouds are formed:
A – in stable atmosphere B – in unstable atmosphere
C – in summer during the day only D – in mid latitudes only
Ref: AIR: atpl, ir; HELI: atpl, ir Ans: B
9194. (Refer to figure 050-02)
Which one of the displayed cloud forms is representative of a cumulonimbus capillatus?
A – D B – A C – B D – C Ref: all Ans: A
9196. Strongly developed cumulus clouds are an indication of:
A – the presence of a low level inversion B – instability in the atmosphere
C – the presence of warm air aloft D – poor surface visibility
Ref: AIR: atpl, ir; HELI: all Ans: B
10213. (Refer to figure 050-03)
Which one of the displayed cloud forms is representative of altocumulus lenticularis?
A – 2 B – 1 C – 4 D – 3 Ref: all Ans: A
10223. In an unstable layer thee are cumuliform clouds. The vertical extent of these clouds depends on the:
A – air pressure at the surface B – wind direction
C – thickness of the unstable layer D – pressure at different levels Ref: AIR: atpl, ir; HELI: atpl, ir Ans: C
10231. A plain in Western Europe with an average height of 500m (1600 ft) above sea level is covered with a uniform CC layer of cloud during the summer months.
At what height above the ground is the base of this cloud to be expected?
A – 15000 – 35000 ft above the terrain B – 7000 – 15000 ft above the terrain C – 1500 – 7000 ft above the terrain D – 100 – 1500 ft above the terrain Ref: all
Ans: A
10235. What is the main composition of clouds classified as high level clouds?
A – Super cooled water droplets B – Ice crystals
C – Water droplets D – Water vapour
Ref: AIR: atpl, ir; HELI: atpl, ir Ans: B
10237. What are the characteristics of cumuliform clouds?
A – Large water droplets, stability, no turbulence, showers and mainly rime ice
B – Small water droplets, stability, no turbulence and extensive areas of rain C – Large water droplets, instability, turbulence, showers and mainly clear ice D – Small water droplets, instability, turbulence, extensive areas of rain and rime ice
Ref: AIR: atpl, ir; HELI: atpl, ir Ans: C
10243. A plain in Western Europe with an average elevation of 500m (1600 ft) above sea level is covered with a uniform AC layer of cloud during the summer months. At what height above the ground is the base of this cloud to be expected?
A – 1500 – 7000 ft above the terrain B – 100 – 1500 ft above the terrain C – 7000 – 15000 ft above the terrain D – 15000 – 25000 ft above the terrain Ref: all
Ans: C
10244. The presence of altocumulus lenticularis is an indication of the:
A – presence of valley winds
B – risk or orographic thunderstorms C – development of thermal lows D – presence of mountain waves Ref: AIR: atpl, ir; HELI: atpl, ir Ans: D
10246. In which of the following conditions is moderate to severe airframe icing most likely to be encountered?
A – Within cloud of any type
B – Below the freezing level in clear air C- In clear air above the freezing level D – In Nimbostratus cloud
Ref: AIR: atpl, ir; HELI: atpl, ir Ans: D
10247. Cumulus clouds are an indication for:
A – stability
B – up and downdrafts
C – the approach of a cold front D – the approach of a warm front Ref: AIR: atpl, ir; HELI: atpl, ir Ans: B
10248. The presence of altocumulus castellanus indicates:
A – stability in the higher troposphere B – strong convection at low height C – instability in the middle troposphere
D – subsidence in a large part of the troposphere Ref: AIR: atpl, ir; HELI: atpl, ir
Ans: C
15793. Which of the following cloud types can project up into the stratosphere?
A – Cumulonimbus B – Cirrostratus C – Altocumulus D – Altostratus Ref: all
Ans: A
16552. Which of the following is most correct regarding the cloud types Stratus and Nimbostratus?
A – Neither cloud type may give precipitation
B – Stratus may give drizzle, ice prisms or snow grains and Nimbostratus may give rain showers
C – Stratus may give rain showers and Nimbostratus may give drizzle, ice prisms or snow grains
D – Stratus may give drizzle, ice prisms or snow grains and Nimbostratus may give continuously falling rain or snow
Ref: all Ans: D
16553. Altostratus (AS) and Nimbostratus (NS) are easily confused. How do you distinguish between them?
A – The cloud base is higher in AS and precipitation, if any, is light B – Precipitation falls from AS but not from NS
C – Steady precipitation from AS D – The sun can be seen through NS Ref: all
Ans: A
16554. Which one of the following cloud types gives steady rain or snowfall?
A – Altostratus B – Nimbostratus C – Cirrostratus D – Cumulonimbus Ref: all
Ans: B
16612. The presence of altocumulus lenticularis is a sign of:
A – severe instability B – anabatic winds C – katabatic winds D – lee waves
Ref: AIR: atpl, ir; HELI: atpl, ir Ans: D
24114. (Refer to figure 050-66)
The cloud most likely to be experienced in square 1E is:
A – CS B – C1 C – AS D – CB Ref: all Ans: B
24115. (Refer to figure 050-34)
The cloud type most applicable to square 2D is:
A – AS B – CU C – CB D – CS Ref: all Ans: A
24116. (Refer to figure 050-34)
The cloud type most applicable to square 3C is:
A – NS B – AC C – AS D – CB Ref: all Ans: A
24118. (Refer to figure 050-34)
During summer, the cloud type most applicable to square 2A is:
A – ST B – AC C – CB D – CS Ref: all Ans: C
24121. (Refer to figure 050-34)
The cloud type most applicable to most of square 3B is:
A – SC B – CS C – AS D – NS Ref: all Ans: A
24129. (Refer to figure 050-58)
The cloud type most applicable to square 1E is:
A – CS B – CB C – NS D – SC Ref: all Ans: A
24130. (Refer to figure 050-58)
The cloud type most applicable to square 2C is:
A – CS B – AS C – CB D – CU Ref: all Ans: B
24131. (Refer to figure 050-58)
The cloud type most applicable to square 2B is:
A – ST B – CS C – CB D – SC Ref: all Ans: C
24209. A cumulus congestus is:
A – a remnant of a CB
B – a cumulus that is of great vertical extent C – a cumulus with little vertical development
D – a cumulus that only occurs in association with the ITCZ Ref: all
Ans: B
24213. A layer of stratus is most likely to be dispensed by:
A – adiabatic cooling due to subsidence
B – absorption of long waved solar radiation in the stratus layer C – the release of latent heat due to precipitation
D – insulation resulting in the lifting of the condensation level Ref: all
Ans: D
24220. About ten identical clouds are in the sky, well isolated from one another, dense, with well defined contours, developing vertically in a cauliflower shape. The side of these clouds lit by the sun is bright white. Their base, relatively dark, is essentially horizontal and at FL 30, and their tops at FL 150.
These clouds are:
A – Altocumulus castellanus B – broken Cumulus humilis C – towering Cumulus D – Stratocumulus Ref: all
Ans: C
24225. After a clear night cumuliform clouds are formed in the morning. Why can the base of these clouds become higher during the day?
A – Because the difference between the temperature and the dew point temperature at the initial condensation level becomes smaller
B – The wind speed is increasing, because the cold air mass changes into a warm air mass
C – Because the stability increases
D – Because the surface temperature increases Ref: all
Ans: D
24254. Clouds in patches, sheets or grey or whitish layers made up of elements resembling large pebbles or rollers, together or not, and always clear of the ground are:
A – Altostratus B – Stratus
C – Stratocumulus D – Nimbostratus Ref: all
Ans: C
24255. Clouds will mainly consist of super cooled water droplets when the temperature is:
A – between -5oC and -30oC B – between 0oC and -15oC C – between -30oC and -40oC D – below -40oC
Ref: AIR: atpl, ir: HELI: all Ans: B
24303. Lenticular clouds in mountainous areas indicate:
A – unstable air B – turbulence C – an inversion
D – light variable winds
Ref: AIR: atpl, ir: HELI: atpl, ir Ans: B
24306. Of what does lenticular cloud provide evidence?
A – Jet streams B – Mountain waves
C – Stratospheric inversions
D – Areas of high level clear air turbulence Ref: AIR: atpl, ir: HELI: atpl, ir
Ans: B
25578. (Refer to figure 050-02)
Which one of the displayed cloud forms is representative of altocumulus astellanus?
A – A B – B C – C D – D Ref: all Ans: C
25622. (Refer to figure 050-01)
Which one of the displayed cloud forms is representative of altocumulus astellanus?
A – 1 B – 2 C – 3 D – 4 Ref: all Ans: C