Use of sleep reporting spreadsheet and potential for modification of data input to meet operator’s minimum requirements
Date issue released
Safety Issue Description

The operator's fatigue risk management system relied extensively on a sleep reporting spreadsheet (sleep log) that was based on the prior sleep wake model, and the spreadsheet had a transparent rule set that made the recorded data easy to modify to achieve results that met the operator’s minimum sleep and wake requirements. In the context of perceived pressure to present as fit for duty, multiple pilots on multiple occasions had entered unrealistic or inaccurate sleep times and there were limited effective controls in place to assure that the sleep times being entered by pilots was accurate.

Issue number
Issue Status
Closed – Adequately addressed
Transport Function
Aviation: Air transport
Issue Owner
Heli-Aust Whitsundays Pty Limited
Mode of Transport
Issue Status Justification

The ATSB is satisfied that the proactive safety action taken by the operator appropriately addresses this issue.

Proactive action
Action number
Heli-Aust Whitsundays Pty Limited
Action Status
Action description

The operator advised that a new fatigue risk management system (FRMS) was developed, consistent with the requirements of Civil Aviation Order 48.1 (Appendix 7). This process included a fatigue study and historic fatigue data analysis conducted by a FRMS subject matter expert. The operator’s FRMS was approved by the Civil Aviation Safety Authority (CASA) for a trial period that commenced on 23 February 2022. The operator’s new FRMS does not include the sleep reporting spreadsheet utilised at the time of the occurrence.

The FRMS utilises a system of tools to manage and measure fatigue, including:

  • a sleep diary integrated in the operator’s Air Maestro system, that predicts the ‘Alert Time’ (based on relevant scientific data), with the flight duty period not allowed to exceed the calculated alert time
  • individual sleep needs are accounted for using a procedure for estimating individual sleep needs (EISN)
  • use of the Karolinska Sleepiness Scale (KSS), to measure the subjective level of sleepiness at particular times of the duty period and criteria established for continuation of any duty period
  • consideration of the effects of travelling across time zones and the period for acclimatisation to the new time zone
  • monthly FSAG (fatigue safety advisory group) meetings, operational audits, fatigue reports and surveys.