Although the operator’s rostering practices were consistent with the existing regulatory requirements, it had limited processes in place to proactively manage its flight crew rosters and ensure that fatigue risk due to restricted sleep was effectively minimised.
The ATSB is satisfied that the changes made by the operator, and the increased requirements relating to fatigue management being imposed by the regulator, will reduce the risk associated with this safety issue.
Although not in response to this occurrence, on 28 March 2013 the Civil Aviation Safety Authority (CASA) released revised fatigue management and flight and duty time requirements in Civil Aviation Order (CAO) 48.1 Instrument 2013. These requirements were to take effect for existing operators on 30 April 2016.
The revised CAO 48.1 stated that, for air transport operations, an operator had to comply with a set of limits and requirements (dependent on the type of operation) or operate to a fatigue risk management system (FRMS), if that FRMS was approved by CASA.
If an operator was not using a CASA-approved FRMS, CAO 48.1 stated that a flight crew member (FCM) must not be assigned or commence a flight duty period at home base unless, within the 12 hours immediately before commencing the duty period, they had at least 8 hours consecutive sleep opportunity. For a duty period commencing away from home base, the 8-hours sleep opportunity must be provided within the previous 10 hours. Sleep opportunity was defined as:
a period of time during an off-duty period when an FCM:
(a) is not meeting the reasonable requirements of bodily functioning such as eating, drinking, toileting, washing and dressing; and
(b) has access to suitable sleeping accommodation without, under normal circumstances, being interrupted by any requirement of the AOC [Air Operator’s Certificate] holder.
Compared to the previous standard industry exemption to CAO 48, the revised CAO 48.1 also provided more restrictions regarding the length of duty periods associated with early starts.
Airnorth advised that, since the time of the occurrence, it had increased its E170 flight crew by about 30 per cent. This increase had resulted in flight crews doing less flight hours and providing more flexibility in rostering the flight crews.
In addition, Airnorth advised that due to changes in schedules, its rostering patterns had changed so that there were no longer any planned rosters that required overnight free of duty periods of less than 10 hours. Occasionally there were actual overnight free of duty periods less than 10 hours when the day’s duty period was extended for operational reasons, but these were relatively rare.
