A light plane that crashed near Canberra last year stalled at an altitude so low the pilot was unable to recover from a fatal spin, a Australian Transport Safety Bureau investigation has found.
The pilot, John Corbett from Picton, died instantly when his single engine Liberty Aerospace nose-dived into the ground near Braidwood NSW, on August 6, 2019 when he was attempting to land at an airstrip.
"A Liberty XL-2 two-seat light aircraft likely stalled at low speed and at a height that limited an effective recovery before it collided with the ground at a rural property near Braidwood," the report said.
Data from a flight planning app on the pilot's iPad showed that the aircraft approached the landing area from the southeast, overflew the homestead before turning left to circle the landing area with a slowing airspeed.
On a second orbit of the strip, at about 400 ft above ground level, and after crossing the marked end of the landing area, witnesses saw his left wing drop before the plane went into a spin.
The pilot was unable to recover control of the aircraft before it hit the ground, the report said.
"The left wing stalled, and this resulted in the aircraft entering into an upright spin at an altitude that limited an effective recovery," ATSB Director Transport Safety Mike Walker said.
"Recovery takes a considerable amount of height, the magnitude of which is dependent on the reaction time of the pilot, and the use of appropriate recovery technique," the report said.
"This investigation highlights the need for pilots to minimise the risk of stalling, particularly when in proximity to the ground, such as during take-off and landing," Dr Walker said.
Turning manoeuvres can lead to a stall that could result in the aircraft entering a spin.
"Pilots can limit their risk of losing control in flight by maintaining situational awareness of the aircraft state while conducting turns, maintaining adequate airspeed through appropriate power application during increased bank angles, and by selecting altitudes to operate at that provide sufficient height to recognise and recover from a stall."
The investigation established that the aircraft's stall warning system was most likely functional at the time of the accident.
However, it is unknown if and for how long this warning may have sounded. How the pilot reacted to the warning before the aircraft stalled is also unknown.
Dr Walker noted there was overdue maintenance that did not contribute to the accident, however, the issue "should have precluded further flight in the aircraft" until it was addressed.
Australian Associated Press