Section 21 (2) of the Transport Safety Investigation Act 2003 (TSI Act) empowers the Australian Transport Safety Bureau (ATSB) to discontinue an investigation into a transport safety matter at any time. Section 21 (3) of the TSI Act requires the ATSB to publish a statement setting out the reasons for discontinuing an investigation.
At 1653 Western Standard Time on 3 September 2015, a British Aerospace PLC AVRO 146-RJ85 aircraft, registered VH‑NJW and being operated by Cobham Aviation Services, was flying from Granny Smith Mine to Perth Airport, Western Australia. During the flight, the flight crew observed an engine vibration indication on the No.1 engine. The crew followed the appropriate checklist procedures, carried out a precautionary engine shut down and advised air traffic control. The flight continued to Perth for landing.
A subsequent maintenance investigation found that the indications of an engine vibration were the result of an instrument display defect. No engine defects were identified. The No.1 engine instruments display was replaced and normal vibration indications were displayed during the subsequent engine run.
The ATSB has determined that the display defect was managed using published operational and maintenance procedures. The ATSB has assessed that there is little potential for the enhancement of transport safety through further investigation of this occurrence. On that basis, the ATSB has decided to discontinue its investigation.