Mystery surrounds exactly why a light plane crashed north of Canberra, killing a grandfather and his three grandchildren.

The four-seater nose-dived into the ground near Gundaroo 12 minutes after taking off from Canberra Airport on October 6, 2023.

It was piloted by Peter Nally . His grandchildren Raphael, 11, Evita, 9, and six-year-old Philomena Smith were the passengers. All died. They had visited the Canberra Zoo and were returning home to Armidale when the aircraft crashed.

The final report into the crash by the Australian Transport Safety Bureau says that the pilot didn't radio for help. Nor were emergency measures taken as the Cirrus SR22 got into difficulty.

There was no post-mortem evidence that he'd had a heart attack or suffered any other sudden medical failure.

The ATSB c

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