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
Heading variations of more than 10 degrees
Glideslope deviations of 1 dot

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 avoid 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

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

Answer 5

“MONITOR RADAR DISPLAY”

Question 6

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

Answer 6

“WINDSHEAR AHEAD” x 2

Question 7

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

Answer 7

“GO AROUND, WINDSHEAR AHEAD”

Question 8

Through which aircraft system is Reactive Windshear alerted?

Answer 8

GPWS Mode 7

Question 9

Which computer provides Windshear detection function?

Answer 9

FAC

Question 10

When is the Windshear Detection function active?

Answer 10

• At take-off, 3 sec after liftoff
  up to 1200 ft
• For Landing, from 1200 ft
  down to 50 ft

CONF 1 has to be selected

Question 11

From what altitude, on approach, does the PWS system start scanning and when does the alerts start?

Answer 11

Starts scanning at 2300 ft
Alerts start at 1200 ft

Question 12

How is the Predictive Windshear function turned on?

Answer 12

Operates when the PWS switch is in AUTO

Question 13

How far out does PWS scan and within what angles?

Answer 13

5 nm out and 30 deg either side

Question 14

What is the scan distance and angles for PWS Cautions and Warnings up to 100 kts on take-off?

Answer 14

Advisory: Out to 5 nm and 30
deg either side
Cautions: Out to 3 nm and 30
deg either side
Warnings: Out to 3 nm and
0,25 nm either side

Question 15

What is the scan distance and angles for PWS above 50 ft on take-off and landing?

Answer 15

Advisory: Out to 5 nm and 30
deg either side
Cautions: Out to 3 nm and 30
deg either side
Warnings: Out to 1,5 nm and
0,25 nm either side

Question 16

When are PWS inhibited?

Answer 16

At takeoff, inhibited from 100 kts to 50 ft

Landing, inhibited from 50 ft

Question 17

What flap setting is recommended in Windshear and why?

Answer 17

Flap 3
This is to get a better climb gradient on a go-around

Question 18

What Vapp are you allowed to set manually on a suspected Windshear Approach?

Answer 18

Vls +15 kts

Question 19

When is RWS system available?

Answer 19

From 3 sec after liftoff to 1300 ft on takeoff

From 1300 ft to 50 ft on approach with minimum Flaps 1