The gent was a 161 Recce Flight veteran, an officer, and as such, deserves respect. He would have had excellent basic training, and he would have had substantial aviation experience.
He served in SVN at a nearly identical time to myself (as an Engineer), and I can tell you, 161 Recce blokes earnt their stripes.
The causes of the crash could be anything from complacency to sudden onset of a medical issue, or simply structural failure in a cheap kit aircraft, that is known to have design weaknesses, that needed modification.
It's entirely possible the aircraft structure could have been overstressed by a former owner - or the current owner (nearly always unintentionally).
It does nothing for thread posters reputations to post opinions that the pilot was a dill, and that he contributed to his own demise by a exhibiting a careless attitude, in numerous areas.
Everyone makes mistakes, some are due to lack of knowledge, some are due to complacency after many years of doing the same thing. Casualness regularly creeps in with recreational flights, and it must be guarded against.
No-one, apart from actual investigators at the scene, has any true idea of what could have caused the crash - and until an official report is formulated, speculation on what might have helped, and what didn't help, remains only that - pure speculation.
Ian Sinnott - military record
It's interesting to note that the local laddie who found the crash site, knew, via his good local knowledge, that only someone on horseback would find the wreckage, such was the nature of the terrain into which Ian crashed.
South Burnett Times - Local who rescued girl from beach in 2016, makes aircraft wreckage discovery