Accident
On 19 February 2015, a Robinson Helicopter Company R44 helicopter registered ZK-IPY was returning to Queenstown from a training flight when it broke up in mid-air and crashed in bush near the Lochy River. The instructor and student on board were killed. The break-up was caused by mast bumping, a condition where the inner part of a main rotor blade or rotor hub contacts the main rotor shaft. No pre-existing defects or mechanical failures were identified. The Commission found that the student was about as likely as not to have been flying the helicopter at the time of the mast bumping, and that weather conditions were suitable for the flight.
Initial Investigation
The Transport Accident Investigation Commission (Commission) opened an inquiry on the day of the accident. The Commission approved a final report for publication on 27 July 2016, which was published on 22 August 2016. The cause of the mast bump could not be conclusively determined.
New Evidence and Resumed Inquiry
On 31 August 2016, the Coroner informed the Commission that the instructor had undergone treatment for a mental health condition in 2014. The Commission resumed its investigation on 28 September 2016 to evaluate this new evidence. Between September and December 2016, the Commission obtained medical records, interviewed medical staff and witnesses, and engaged a senior psychiatrist, Dr Mark Davis, to review the evidence.
Findings on Medical Fitness
The Commission concluded that it is very unlikely that any medical factor contributed to the accident. It further found that it is very likely that the instructor was medically fit to fly when his most recent medical certificate was issued. The instructor had self-referred for counselling in February 2014, visited his GP for sleeping and anxiety in late March 2014, and was diagnosed with depression with anxiety. He stopped taking medications in early August 2014 and resumed flying on 1 September 2014. On medical certificate applications dated 17 August 2014 and 4 February 2015, he reported sleeping problems but did not disclose the medication or mental health condition. His class 1 medical certificate was re-issued on 21 August 2014 without restrictions.
Systematic Issues and Recommendations
The Commission identified that there are currently too many ways for aviation document holders to circumvent the civil aviation process designed to prevent pilots from flying if they are not medically fit. It also found low awareness among medical practitioners of their duty to report to the Civil Aviation Authority (CAA) when a pilot develops a medical condition that would render them unfit to fly. The Commission recommended that the Director of Civil Aviation improve mechanisms for informing medical practitioners of the reporting requirement and review the medical application process to better identify potentially serious health issues. Additionally, it recommended that the Chief Executive of the Ministry of Health consider adding a person's occupation to the national electronic health record database and a mechanism to alert health practitioners of their obligation to notify the appropriate authority when a patient in a safety-critical occupation has a potentially adverse health condition.