Originally Posted by
Stagformation
In my time I flew with a Skipper who never flew above F390. All sorts of justification given for the fuel plan, but the real reason was fear of exposure to cosmic radiation.
Think that is a real issue for air crews, but not confident that staying below 40,000 feet helps a lot.
It is a topic that deserves serious medical study, but I've not seen anything large scale, although it should be easy based on flight logs.
Both the unions as well as the regulatory agencies should have ample data for a preliminary evaluation.