Wind

Question 1

Convective currents

Answer 1

• plowed grounds, sand, rocks, and barren land absorb large amounts of solar energy quickly and releases a large amount of heat.
• water, trees, and other areas of vegetation tend to absorb energy more slowly and releases heat slowly causing uneven heating of the surface.

Question 2

The effects of obstructions on wind?

Answer 2

• Obstructions on the ground effects the flow of wind, and can be an unseen danger.
• large buildings, hangars, mountains, and canyons can break up the flow of the wind and create wind gusts that changes rapidly in direction and speed.

Question 3

Low level wind shear

Answer 3

• sudden drastic change in wind direction and speed.
• rapidly effects the performance of the aircraft
• can subject the aircraft to violent updrafts and downdrafts
• can occur at any altitude but low level is hazardous due to being close to the ground
• commonly associated with passage of fronts, temperature inversions, and strong upper level winds.

Question 4

Microburst

Answer 4

• most severe type of low level wind shear
• strong downdrafts up to 6,000 ft per min
• 1-2 miles and 1,000 ft in depth
• lifespan of 5-15 min
• headwind loss of 30-90 knots
• strong turbulence
• hazardous wind direction changes
• performance increases and decreases
• only cue is a visible ring of blowing dust