//www.atsb.gov.au/publications/investigation_reports/2017/aair/ao-2017-096/
The aircraft (Diamond) entered a developed spin during manoeuvres consistent with advanced stall recovery training which likely included intentional incipient spins. The spin continued until the aircraft collided with terrain. The instructor and student were fatally injured and the aircraft was destroyed.
What the ATSB found. The ATSB found that the aircraft limitation prohibiting intentional spins was intended to include incipient spins. However, the manoeuvre was not defined and some operators considered that the manoeuvre was not an intentional spin. In addition, the aircraft was not certified for developed spin recovery, and the capability of the aircraft to recover from a developed spin had not been established nor was it required to be.
While competency at recovery from an incipient spin is still a requirement for the PPL has CASA addressed the situation if spinning is prohibited in the aircraft type (Cessna 172 et al) See ATSB comments above..