The aircraft system to be used in the event of a main deck cargo smoke event on the operator’s B737 fleet was being routinely used by the operator’s engineering personnel in Darwin as a means to cool the flight deck. This practice had become normalised as a result of the perceived benefit of doing so, but there were insufficient risk controls in place to ensure that the aircraft would be returned to the correct configuration prior to departure.
Airwork provided advice of proactive safety action to immediately cease the unauthorised practice and also improve its processes and documentation to prevent a reoccurrence. In conjunction with its other proactive safety actions, the ATSB considers this will be sufficient to address the safety issue.
Airwork advised that: