Thanks Jabawocky- for your comment/s, awarness or experience as it were....
At the get go, Nil experience with RAAus/or the Jabiru itself, and may or may not understand the situation as well as those involved- but have friends with family who operate one, with all manner of family and children onboard from time to time......... as one does. The machine, 'I believe' to be on its 3rd engine.
From an outsider or broarder Aviation / Saftey System standpoint, it would appear that, 'they've' identified 2x Modes of Engine Failure- being, 1) failure of the Valve Train and 2) failure of Engine Crankcase Through-Bolts. With both issues going back 'some' (considerable) period of time.
To address/mitigate these issues (that to me, 'appear' repetitive and indeed systemic), the manufacturer has issued a series of Service Bulletins, over time- that, as pointed out (above) are not in themselves 'prescriptive', for want of a term....- without going into defined definitions.
The issues 'appear' to me, to be beyond say the repetitive failure of an Accessory Drive for example- indeed both result in significant/total failure of the engine/power plant, and resultant Thrust.
If one ran these issues through a James Reason Safety Model (as the rest of Commercial/RPT Aviation has to do) at what point, given the longevity of the matters, do (/did) the holes start lining up in the cheese..........???, and is something prescriptive, auditable and/or accountable required at this time, be that an Airworthiness Directive or some such....????
Is that where The Regulator (/and RAAus) are now at....????
Rgds
S28- BE
Note: in no way endeavouring to be provocative- and wish all involved well in resolving these matters- affecting at the end of the day, an AUS Manufacturer.