ATSB – Aircraft flight preparation occurrence involving Boeing 787
IFA Comment: When performing safety‑critical tasks like aircraft maintenance, it is very important that procedures are clear and unambiguous to avoid misinterpretation and error such as occurred in this incident.
Safety summary – Link here to read the full investigation Report
On the evening of 21 September 2021, a Boeing Company 787-9, registered VH-ZNJ and operated by Qantas Airways was prepared for a freight flight from Melbourne, Victoria, to
Los Angeles, United States. This involved removing covers from the pitot probes and static ports, among other tasks, associated with restoring the aircraft to flight status following an aircraft ‘park’ procedure.
At about 0825 on 22 September 2021, a pre-flight exterior inspection was conducted by one of the flight crew, with no anomalies detected. The aircraft was also subject to a pre-departure exterior inspection by ground service dispatch personnel, before departing Melbourne at about 0900. The aircraft landed at Los Angeles about 14.5 hours later, following an uneventful flight. During the post-flight inspection, engineering identified that all 4 engine fan cowl static ports were covered with tape.
What the ATSB found
The ATSB found that tape covering the 4 fan cowl static ports was not removed by engineering, as per the manufacturer’s procedures, nor identified by flight crew or dispatch during pre-departure checks. This resulted in the aircraft departing with reduced redundancy to the engine electronic control system. Despite that, the flight crew reported the flight was uneventful, and a review of the flight data confirmed there was no adverse effect to aircraft or its engine systems.
What has been done as a result
In addition, the operator has amended the aircraft ‘park’ and ‘restore’ engineering instructions to reference the manufacturer’s procedures. Further, these instructions will now identify the static port locations, to ensure consistency in maintenance practices.
Following the occurrence, the operator distributed memos to engineering, flight and ramp crew, highlighting the location of the fan cowl static ports and that they may be covered when aircraft were parked for certain periods. The memos further reinforced the importance of following the documented engineering, pre-flight and dispatch procedures.
When performing safety‐critical tasks like aircraft maintenance, it is very important that procedures are clear and unambiguous to avoid misinterpretation and error such as occurred in this incident.
‘Remove before flight’ streamers are a reminder to remove covers, or lockout devices, prior to flight. Failure to remove these devices and covers can prevent the functionality of certain aircraft systems. In certain circumstances, the streamers may be fixed to the aircraft and not hang freely, which can reduce their visibility. Targeted inspection of locations and components, rather than relying on streamers, which can detach, can help to identify when these covers or devices have not been removed.