A Victorian pilot made the fatal decision to fly solo in a vintage plane after telling his instructor he would practise on the ground ahead of their scheduled lesson.
Keith Astrella, 69, was killed trying acrobatic manoeuvres at Latrobe Regional Airport on September 7, 2018 in regional Victoria.
A report on the accident found the Berwick man had previous experience performing basic aerobatics, but never in the WWII fighter plane, a single-engine Yakovlev Yak-9UM Warbird.
The Australian Transport Safety Bureau heard the instructor helped Mr Astrella start the plane's engine around 2pm, before leaving him alone to carry out taxiing practice on the ground.
They had an instructional flight scheduled for 4.30pm.
Instead Mr Astrella took off about 2.20pm and witnesses saw the plane performing a mid-air loop before it began spiralling towards the ground about ten minutes later.
The plane had been travelling about 2800 feet above ground at 206 knots before it crashed into a paddock, killing him.
The report notes the flight was Mr Astrella's first in the aircraft for three months.
He was endorsed for aerobatic manoeuvres at 3000 feet, but he had not previously conducted aerobatics in the YAK 9.
"Depending on pilot experience 5000 to 7,000 feet is required to safely recover the aircraft from a developed spin," ATSB Transport Safety Director Stuart Macleod said.
"With limited experience and recency in flying the YAK 9, the pilot was likely unaware of the aircraft's unique handling characteristics during aerobatic manoeuvres."
An annual Keith Astrella Memorial is held in Victoria by the Victorian Compact Speedcar Club in his honour.