If you have to say "I was fatigued because I..." it's probably your fault.

- I didn't sleep because my kids
-I had a drink
- My commute
- fighting with wife
-fighting with xwife
- girlfriend missed me.... 3 times
-the guy in my crash pad snores at 137Db ect...

If your fatigue was induced by the operation:
LATE flights...
MX
Flew unexpectedly into the WOCL
Compounding fatigue catches up to you, maybe you extended the day before and got min rest the next...
Circadian flip flops shows at 2300 followed by a 0430 28hrs later...
Hotel issues, rooms not ready, hockey tournament kept you up all night
maids opening up your do not disturb sign door, the elevator was next to your room...


Just pull up the Fatigue FCIR and read through it. Read the FRPM.

Don't fly fatigued. It's not safe, and it's illegal. If you have an incident, they'll ask you about your previous rest. If you extended why you extended and how come you didn't know you were fatigued at the end of your flight even though you felt fine to start. Fatigue is difficult to assess especially when fatigued. It's all spelled out in the Fatigue Manual.

Even if it is your fault and you are fatigued the responsible thing to do is to call out ASAP to give the operation as much time to recover as possible