As to your comments on the ATSB findings on the Community Service Flight accident rate I'd like to see a counter argument on their stats, using statistical analysis, not just someone in a senate hearing claiming they got it wrong. By saying this I'm not making judgement on it, but it would be pretty stupid of them to just randomly make statements like that when it would be easy enough to get a statistician to review it. I would add I think CASA and the ATSB are way too close for my comfort.
The Angel Flight submissions put up a ‘counter argument’ to the ATSB’s (selective) use of stats.
Angel Flight rejects the claim in the ATSB report that, for Angel Flight passenger carrying flights, the “fatal accident rate was more than seven times higher per flight than other private flights” as invalid.
A valid analysis addressing passenger risks would require comparison of passenger carrying Angel Flights and other passenger carrying private flights. Since no such data are available for other private operations, the only reasonable comparison is between all Angel Flight operations and all other private operations. Even then, results must be treated cautiously because an unknown proportion of private operations involve circuit training and short local flying whereas all Angel Flight operations involve flights with an average sector length of 1.5 hours.
The analysis in Table B2 on page 69 shows that, when all Angel Flight sectors are included, the fatal accident rates are 0.5 and 0.2 per 10,000 flights for Angel Flight and other private flights respectively, and the difference is not significant. Furthermore, when all accidents are included, the rates are 1.1 and 1.5 per 10,000 flights for Angel Flight and other private flights respectively.
And where is the ATSB finding to the effect that lack of maintenance or any airworthiness issue had any causal connection with either of the Angel Flight accidents? There is none. Yet ‘someone’ decided to mandate more maintenance for aircraft engaged in Community Service Flights, despite the evidence that it will increase risk (and cost). I’d like to see a ‘counter argument’ to this:
https://www.savvyaviation.com/wp-con...ton-effect.pdf
Being the defenceless end of the ‘food chain’, GA just has to cop whatever intuition-based mumbo jumbo the safety zealots come up with.