The Australian Transport Safety Bureau has released a preliminary report from its ongoing investigation into the in-flight break-up of a Van’s Aircraft RV-7A amateur-built light aircraft about 90 km south of Charters Towers, Queensland on 23 April 2021.
The pilot, the sole occupant of the aircraft (which had been issued its special certificate of airworthiness in August 2020), had been taking part in a multi-day tour flying in company with three other pilots, each flying their own aircraft.
Prior to departing from Winton for Bowen on the morning of 23 April, the four pilots discussed the forecast weather conditions for the planned flight. Consequently, the other pilots elected to fly to Bowen under the instrument flight rules, while the pilot of the Van’s, who was restricted to operating in visual meteorological conditions, departed under a visual flight rules flight plan.
“Bureau of Meteorology forecasts indicated there was significant cloud, reduced visibility and adverse weather predicted for the duration of the flight, including severe icing and turbulence associated with isolated thunderstorms and cumulonimbus close to the coast,” ATSB Director Transport Safety, Dr Mike Walker said.
Recorded data shows on departing Winton at about 7:51 am the pilot set a north-east course to track to Bowen, climbing to an altitude of 7,500 ft. Near Catumnal Station the aircraft was then descended initially to about 500 ft above ground level and conducted a series of low-speed orbits. The aircraft then overflew the station’s airstrip before conducting a right-hand turn (descending to below 50 ft above ground level) and turning towards Winton.
“A witness at Catumnal Station later recalled to the ATSB hearing an aircraft overhead consistent with the recorded flight data but was unable to visually identify the aircraft due to fog,” Dr Walker noted.
About 11 km after turning towards Winton, the aircraft conducted a left climbing turn and resumed heading towards Bowen, climbing to an altitude of about 10,500 ft. As the flight continued, flight data then shows the aircraft conducted a large left orbit at 1,000 ft above ground level about 290 km north-east of Winton before turning towards Bowen again and climbing to an altitude of 9,000 ft.
“At about 370 km north-east of Winton and about 90 km south of Charters Towers, the aircraft conducted a right turn with a series of airspeed and altitude variations,” said Dr Walker.
“The aircraft sustained an in-flight break-up at 9:51 am, with the accident site located almost directly below the last known reliable radar data point.”
The pilot was fatally injured and the aircraft was destroyed.
Examination of the accident site by ATSB transport safety investigators revealed wreckage was distributed over a distance of about 1.5 km, with the larger and heavier aircraft sections located closer to each other, and lighter, smaller sections of wreckage north-west of the main wreckage.
Dr Walker noted the preliminary report does not include any safety findings or analysis, which will be detailed in the investigation’s final report.
“As the investigation progresses the ATSB will continue to analyse the aircraft builder log, recent flight and pilot training records, electronic flight data, meteorological conditions, and the sequence of the in-flight break-up,” he said.
A final report will be released at the conclusion of the investigation.
“However, should a critical safety issue be identified during the investigation, the ATSB will immediately notify relevant parties so appropriate and timely safety action can be taken.”Last update 27 July 2021