Commercial Fixed Wing
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Fatigue
No Specific Anomaly Occurred All Types
General None Reported / Taken
Human Factors; Company Policy
Regarding Pairing (number): if this isn't a textbook example of a 'circadian swap'; then I don't understand the concept (which is possible). I have never felt as sleep-deprived to the point of significant performance deficit as I did on the last leg of this trip - an ETOPS flight arriving in the early; fog-prone; hours of the morning. Thankfully; the weather was good and the flight uneventful. My sleep strategy was to stay active till time to sleep a solid minimum eight hours; getting up early enough to be physically active again till time to go back to bed for a minimum of four more hours.  On this trip that four-hour nap was nearly impossible. This strikes me as a setup for an incident or accident. Is there a scientifically proven strategy for preparing one's brain and body for a graveyard shift after two early morning duty periods? -for shifting one's circadian clock that dramatically over a 35-hour rest period? If so I'd sure like to know what it is.
Air carrier Captain reported he was extremely fatigued on his flight because of the mix of early morning and late night duty periods.