Originally Posted by
goaround2000
1)Time since awake.
2)Sleep debt.
3)Duty limitations.
4)Circadian rhythm patterns.
All equally important, and all affecting not just duty days and rest periods, but commuting, show times, time zone differentials, sleep patterns before and during the pairing, uniform physiological limitations, scheduling practices, pairing construction, among others.
Agree about the complexity issue. I think #4 is what affects me the most, and causes #2, then tack on #3 and #1.
Having a 4 day pairing with THREE consecutive 4-430 am wakes ups (2-230 my time), and trying to go to bed at 8-9 pm local (6-7 pm my time) is a royal PITA.
My favorite are some of the studies that talk about how to deal with fatigue, especially when it says something along the lines of "try to get your body on the schedule of your trip a couple days before starting it"
What the heck am I supposed to do on my few days off?