On 15 May 2013, an ATR-GIE Avions de Transport Regional ATR72-212A (ATR72), registered VH‑FVR and operated by Virgin Australia Regional Airlines Pty Ltd (VARA), was conducting an instrument flight rules flight from Brisbane Airport to Moranbah Airport, Queensland. During the visual approach to Moranbah, the aircraft descended to a height of 440 ft above ground level as the pilot manoeuvred to avoid cloud. As the pilot levelled the aircraft, a number of terrain awareness warning system (TAWS) ground proximity warning system alerts activated. The aircraft was climbed and the circuit was continued, with the activation of another TAWS alert prior to the aircraft landing.
What the ATSB found
The ATSB found that the captain’s rapid decision to descend limited the opportunity to discuss alternative approach options, descent limits and go around options should visibility reduce to below that required for visual flight.
The ATSB also identified significant under reporting by VARA of ATR72 TAWS-related occurrences to the ATSB.
What's been done as a result
VARA advised the ATSB of a number of safety actions following this occurrence. This includes the incorporation of the ATR fleet into the company’s cyclic recurrent check programme, the provision of safety promotion briefings to all company pilots, and the production of safety publications that alert crew to the defences that standard operating procedures and threat and error management provide.
In addition, VARA directed its flight crew to submit occurrence reports for all ground proximity warning system (TAWS) occurrences and implemented a review process to ensure that all relevant reports are passed to the ATSB. A review of the ATSB database in the period since these initiatives and the production of this investigation report showed that VARA’s reporting of TAWS occurrences was now consistent with other similar operator/operation reporting rates.
This occurrence highlights the importance to flight crew of good communication and the inherent risk of spontaneous decision making. In addition, the advantages of following procedural information contained in operational documentation and aeronautical publications, such as the Aeronautical Information Publication Australia, is evident.