Australian investigators have concluded that a light training aircraft collided with fruit bat, rather than a drone, during an approach to Parafield airport.
The Socata TB10 sustained damage to its starboard wing in the 11 July collision, which was initially suspected to have involved an unmanned aerial vehicle.
But DNA analysis of swabs taken from the wing have shown that the aircraft hit a grey-headed flying fox, says the Australian Transport Safety Bureau.
Flying foxes can have a wingspan of around 1m and the inquiry says the finding is "consistent with the known behaviours" of the bats, which can travel up to 50km from roosts at night.
Airline pilot school Flight Training Adelaide is the operator of the single-engined TB10.