"Half of FDX flying is daytime"
Is that true? Seems kinda high.
All I know is at my pax airline it seems like virtually no one wants the red eyes. Like NO ONE. I have been trading into them because they are super easy 1 leggers with really only the return leg being a true red eye. The leg out to the west gets in you in time to go drinking. Anyways, even with my ho hum attitude about red eyes, I am very aware of the affect if has on my body. The affect FOR ME, has gotton worse as I have gotten older. Similiar to going out all night drinking. In my 20's, not a problem, in my late 40's? I can do it but I pay for it the next day.
I have to believe back side of the clock flying reduces life span in ways that are hard to measure.
But as Motor said "Gotta die from something"