A good place to start is with the definition of aerobatics :
The International Civil Aviation Organization defines aerobatics as “maneuvers intentionally performed by an aircraft involving an abrupt change in its attitude, an abnormal attitude, or abnormal variation in speed.”
CASA used to have that exact same definition but in September 2015 they changed it to:
“aerobatic manoeuvres, for an aircraft, means manoeuvres of the aircraft that involve:
(a) bank angles that are greater than 60°; or
(b) pitch angles that are greater than 45°, or are otherwise abnormal to the aircraft type; or
(c) abrupt changes of speed, direction, angle of bank or angle of pitch.”
Why did CASA change their definition of aerobatics?
The USA and Europe have definitions which are almost exactly like the ICAO definition. The USA has an additional rule requiring the wearing of parachutes in some circumstances when an aircraft exceeds 30 degrees of pitch or 60 degrees of bank relative to the horizon; their definition of aerobatic flight, however does not specify pitch attitude or bank angle. EASA has an additional rule clarifying that training undertaken for a licence is not aerobatics.
Why did CASA remove the word “intentionally” from the definition of aerobatics? Consider what CASA requires for training towards a licence and consider whether any unintentional wing-drop etc is aerobatics per CASA’s definition. Not a problem of course if it is a dual flight and the instructor has an aerobatic training endorsement.