WINDSHEAR

Question 1

What is the definition of windshear?

Answer 1

A sudden change of wind velocity and/or direction

Question 2

What are the some of the criteria that would be used to define what is considered as windshear?

Answer 2

IAS variations of more than 15 kts
Vertical speed changes of more than 500 ft/min
Pitch changes of more than 5 degrees
Glideslope deviations of more than 1 dot
Heading variations of more than 10 degrees

Question 3

What is the difference between Predictive Windshear and Reactive Windshear?

Answer 3

Predictive Windshear warns ahead of the aircraft and gives guidance to aviod it.
Reactive Windshear gives warning when in the windshear

Question 4

From where does Predictive Windshear and Reactive Windshear get it’s information respectively?

Answer 4

Predictive Windshear uses doppler weather radar to detect disturbed air.
Reactive Windshear uses a comparison between inertial and aerodynamic data. i.e is the plane behaving as expected

Question 5

How is the Predictive Windshear function turned on?

Answer 5

By pressing the WXR button on the EFIS control panel.

Question 6

Below what altitude is Predictive Windshear caution/warning active?

Answer 6

Active below 1’200 ft. Starts scanning from 2’300 ft on approach but no alarms until below 1’200 ft

Question 7

What is the Predictive Windshear caution aural alert on the ground and in the air?

Answer 7

“MONITOR RADAR DISPLAY”

Question 8

What is the Predictive Windshear warning aural alert on the ground?

Answer 8

“WINDSHEAR AHEAD” x 2

Question 9

In what area is the Predictive Windshear caution and warning alerting for on the ground?

Answer 9

Caution looks 25 degrees either side starting 0,5nm from the aircraft out to 3nm
Warning looks in a narrow band of 0,25nm either side of the aircraft out to 3nm

Question 10

In what area is the Predictive Windshear caution and warning alerting for in the air?

Answer 10

Caution looks 25 degrees either side starting 0,5nm from the aircraft out to 3nm
Warning looks in a narrow band of 0,25nm either side of the aircraft out to 1,5nm

Question 11

What is the Predictive Windshear warning aural alert in the air?

Answer 11

“GO AROUND, WINDSHEAR AHEAD”

Question 12

Through which aircraft system is Reactive Windshear alerted?

Answer 12

GPWS Mode 7

Question 13

Below what altitude is Reactive Windshear active?

Answer 13

Below 1’500 ft

Question 14

When are PWS alerts inhibited on take-off?

Answer 14

Above 100 kts up to 50 ft