If by accurate CO detector? I presume you’re referring to that unlit, aged plastic thing with a circle which is supposed to turn dark in the presence of CO and is stuck to the lower far right side of the panel. Then the answer is yes. Many, many single pilot, night hours with the Janitrol heater going full blast. None of which makes me any the wiser on CO poisoning.
You presume wrongly. Those aged plastic things with a circle are useless. If you'd take the time to watch the video I posted, you'd know why.
This is the type I fly with at the moment:
https://www.candoitaustralia.com.au/...-ios-app-white
I've used other different types.
They measure and display CO concentration in parts per million and give an audio and visual alarm above set levels of CO concentration.
My comment was to do with the unintended excess of outside fresh air flowing through the cockpits of the Beavers I flew and the then presumed likelihood of this diluting the CO concentration.
Again, a presumption. I say again (for the last time) the highest levels of CO I measured in the cockpit of the serviceable aicraft I flew for hundreds of hours (now sold) were during taxi with all the windows open. Prolonged exposure at those levels would have been deleterious. My current aircraft varies from 1 to 3 ppm in the cruise, depending on how the vents are set.
Most of what people believe about airflows through cowls and cockpits and cabins is based on mere intuition that has been disproved by actual testing.
What the ATSB should have done / do is get another Beaver, remove the same firewall fasteners, and make some measurements with an accurate CO detector during various operations and window/vent configurations.