Turnulence

Question 1

What is convection turbulence?

Answer 1

On a sunny day the earth heats up and produces a temperature rise. The heat is transferred to the air. The strength of the convection current will vary according to the temperature rise.
Can be made when cold air moves over warm air.

Question 2

What is mechanical turbulence?

Answer 2

Turbulence caused by the wind going over mountain ranges or buildings. If blown at right angles can cause mountain waves

Question 3

What is wind sheer?

Answer 3

A rapid change of wind speed and/or direction over a short distance horizontally or vertically.

Question 4

When does wind sheer occur? ( list the 5 times)

Answer 4

1) climbing/descending through an inversion layer
2) climbing/descending through a warm front
3) in the Lee of high ground/close to the ground
4) in the vicinity of standing waves
5) flying near a CB

Question 5

What is a microburst?

Answer 5

A localised column of skinny Air (down draft) within a thunderstorm and is usually less than or equally to 2.5miles in diameter

Question 6

When is a low level wind sheer alert issued?

Answer 6

• mean surface wind 20kts
• A difference between surface and 2,000ft wind speeds of 40kts
• TS/+RA/+SNSH within 5nm if the airfield.
• pilot reports windsheer Conditions

Question 7

What is a macroburst?

Answer 7

Downdraft more than 4km(2.5miles) in diameter. Can produce wind as high as 135mph

Question 8

What is Clear Air turbulence?

Answer 8

Turbulence that occurs without any cloud to indicates its presence