DHC Beaver down in Hawkesbury

[Lead Balloon]

How do you account then for the CO in the blood samples?

Wild guess: The people with CO in their bloodstreams had been breathing air containing CO? The differing levels were the result of differing air flows through the cabin and differing accumulated times in the cabin of the PIC compared with other POB?

I’m not ‘welded’ to CO as the cause. I’m pleasantly surprised that the ATSB is occasionally capable of entertaining the possibility that the cause of an accident is not PIC stuff up. If you look objectively at the evidence as to the weird and whacky ways in which air flows through aircraft bits and the insidious effects of CO, you don’t have to be Sherlock Holmes to join the dots between a gaping crack in an exhaust pipe and CO levels in the PIC’s bloodstream that had insidious effects on his judgment.

What’s your theory as to the cause/s of the tragedy?