Failure to remove pitot tube covers before flight has been the cause of several incidents in recent years, according to a Safety Advisory Notice published by the Australian Transport Safety Bureau (ATSB). One of the latest such instances occurred on July 18 involving a Malaysia Airlines-operated Airbus A350 at Australia's Brisbane Airport.

The Malaysia Airlines pilots detected an airspeed anomaly, including red speed flags on both primary flight displays, but continued the takeoff and climbout and carried out several checklists before returning to the airport. A subsequent inspection after the aircraft landed identified that covers were fitted to the aircraft’s three pitot probes.  

Investigation by the ATSB into the incident is continuing, and the reasons and context associated with the covers not being removed before flight, “and the takeoff being continued with unusable airspeed information, are still being examined.” 

Malaysia Airlines did not routinely use covers for turnarounds. However, shortly after the previous flight on July 18, covers were attached by a local maintenance technician. “Due to miscommunication, the operator’s certifying engineer was not aware of their fitment, and subsequent inspections during the turnaround by personnel from the operator and the ground handling service provider did not identify that they had been fitted,” despite the fact that the covers had red “remove before flight” flags hanging from them.

The ATSB is advising operators that use pitot probe covers to “ensure there are rigorous processes for confirming that covers are removed before flight.” A review for similar incidents in the U.S. revealed no NTSB investigations, but at least 10 incidents reported to the Aviation Safety Reporting System (ASRS).