Airspeed Unreliable

Question 1

What are possible causes of unreliable airspeeds?

Answer 1

• Damage to AOA vanes, pitot/static tubes, ADIRU system
• Damage to radome

Question 2

Symptoms of unreliable airspeed

Answer 2

• Spurious stick shaker
• Spurious PLIs shown on PFD
• Spurious minimum/maximum speed bars
• Failure flags
• AOA DISAGREE
• IAS DISAGREE
• ALT DISAGREE

Question 3

Memory items for unreliable airspeed

Answer 3

1. Disconnect autopilot & autothrottle
2. Turn off FDs.
3. Maintain pitch and power values:

Flaps UP/Clean - 4ª / 75% N1

Flaps extended: - 10º / 80% N1

Question 4

Actions for unreliable airspeed on takeoff:

Answer 4

Ensure gear is raised, initially pitching to 15º prior to acceleration height, then memory items, as before.

Question 5

What is the source of reference if indicated airspeed cannot be positively determined?

Answer 5

Airspeed Unreliable tables in P.I section of the QRH.

Question 6

What are the different phases of flight in the QRH Performance Inflight Tables

Answer 6

Climb
Cruise
Descent
Terminal Area
Final Approach (3º GS)
Go-Around

Question 7

REVISIT RAW DATA NOTES - What is the raw data pitch and power profile for a normal takeoff?

Question 8

REVISIT RAW DATA NOTES - What is the raw data pitch and power profile for final approach? Weights?

Question 9

REVISIT RAW DATA NOTES - What is the raw data pitch and power profile for a go around

Question 10

REVISIT RAW DATA NOTES - What is the raw data pitch and power profile for normal descent

Question 11

REVISIT RAW DATA NOTES - What is the raw data pitch and power profile for a normal holding ?