Aviation safety investigations & reports

Unreliable airspeed and altitude indications involving Boeing 737-476SF, ZK-TLJ, about 167 km west of Meekatharra Airport, Western Australia, on 10 June 2022

Investigation number:
Status: Active
Investigation in progress


The Australian Transport Safety Bureau (ATSB) is investigating an unreliable airspeed and altitude indications involving a Boeing 737-476SF, registered ZK-TLJ, that occurred on a flight out of Perth Airport, Western Australia, on 10 June 2022.

During the cruise, the flight crew noted a discrepancy between the captain and first officer’s indicated altitude, indicated airspeed, and Mach number. After consulting maintenance watch, the flight crew elected to return to Perth Airport.

A final report will be released at the conclusion of the investigation. However, should a critical safety issue be identified during the course of the investigation, the ATSB will immediately notify relevant parties so appropriate safety action can be taken.

General details
Date: 10 June 2022   Investigation status: Active  
Time: 0249 UTC   Investigation level: Short - click for an explanation of investigation levels  
Location   (show map): about 167 km west of Meekatharra Airport   Investigation phase: Examination and analysis  
State: Western Australia   Occurrence type: Avionics/flight instruments  
  Occurrence category: Incident  
Report status: Pending    
Anticipated completion: 4th Quarter 2022    

Aircraft details

Aircraft details
Aircraft manufacturer The Boeing Company  
Aircraft model 737-476SF  
Aircraft registration ZK-TLJ  
Serial number 24432 LN:1879  
Type of operation Air Transport High Capacity  
Sector Jet  
Damage to aircraft Nil  
Departure point Perth Airport, Western Australia  
Destination Christmas Island Airport, Christmas Island  
Last update 16 August 2022