Worksheets14 Turbulence
Total questions: 15
Worksheet time: 1hrs 15mins
Where is standing wave maximum turbulence most likely to exist?
two wavelengths downwind from the crest and just above its surface.
approximately one wavelength down wind of, and approximately level with, the top of the ridge
Just below the tropopause above the ridge
Down the lee side of the ridge and along the surface
During the formation of a mountain wave, what characteristic should be within the wind that is above the level of the ridge over which it is being generated?
Decrease or even reverse direction.
Increase initially then decrease.
increase with little change in direction.
Increase and then reverse in direction.
Which of the following is probably the most dangerous practice, when flying in IMC in a region close to a range of hills 2000 ft high AMSL, in stable air and with wind direction at right angles to the axis of the range of hills?
Flying towards the hills, into the wind, at altitude 6500 ft AMSL
Flying parallel to the hills on the downwind side at altitude 4000 ft AMSL
Flying towards the hills downwind at altitude 5500 ft AMSL
Flying parallel to the hills in the upwind side at altitude 4000 ft AMSL
Which of the following statements referring to Jet Streams is correct?
CAT associated with Jet Streams is probably associated with the rapid wind shear in the vicinity of the jet.
The maximum windspeed in a Jet Stream increases with increase of height up to the tropopause and remains constant thereafter.
The core of a Jet Stream is usually located just below the tropopause in the colder air mass.
The rate of change of windspeed at any given level is usually greatest on the warmer side of the jet.
What can be determined from the observation of the existence of lenticular clouds?
There may be mountain waves present and there will be severe turbulence.
There are mountain waves present but they may not give severe turbulence.
A Fohn wind can be expected with no turbulence.
A Katabatic wind is present which may lead to fog in the valleys
For standing waves to form, the wind direction must be near perpendicular to a ridge or range of mountains and the speed must:
Decrease with height within a stable layer above the hill.
increase with height within an unstable layer above the hill.
Decrease with height within an unstable layer above the hill.
increase with height within a stable layer above the hill.
A mountain range, height 10,000 ft AMSL is producing marked mountain waves. Where will the greatest potential danger exist for an aircraft?
on the windward side of the ridge
at FL 350 over and parallel to the ridge
towards the ridge from the lee side at 14000 ft AMSL
above a line of clouds parallel to the ridge on the lee side at 2500 ft AMSL
Clear air turbulence, in association with a polar front jet stream in the Northern Hemisphere, is
Underneath the jet core
In the centre of the jet core
Looking downstrearn on the right hand side
Looking downstream on the left hand side
Mountain waves can occur ...
Up to a maximum of 5000 ft above the mountains and 50 nm to 100 nm downwind.
Up to mountain height only and 50 nm to 100 nm downwind.
Above the mountain and downwind up to a maximum height at the tropopause and 50 nm to 100 nm downwind.
In the stratosphere.
What intensity of turbulence should be reported if crew and passengers feel a definite strain against their seat or shoulder straps, food service and walking is difficult and loose objects become dislodged?
Light
Extreme
Severe
Moderate
Refer to the image.
What is the most likely wind strength in square A3?
35 kt
50kt
25 kt
light
Refer to the image.
What is the most likely wind strength in squares A4, B4 and C4?
50 kt
40 kt
35 kt
a jet stream
Refer to the image.
What is the most likely flight condition(s) in square B1?
Smooth
Turbulent
Turbulent due to rotor activity
Turbulent in breaking wave crests
Refer to the image.
Where is the most violent/extreme turbulence occurring?
in square A2
in square B1
in squares A4, B4 and C4
in squares B2, B3, B4 and in Squares C2, C3 and C4
Updrafts and downdrafts are the same as turbulence. True or false?
True
False
