B757 captain reported a taxiway incursion during taxi out due to fatigue; after a maintenance delay.

Narrative:

Flight was air return due to airborne mechanical event. Upon taxi out; second time around; we were all tired from the air return plus being into our window of circadian low (wocl) on taxi out. ATC cleared us to taxi to 22L via RF; alpha and sierra. We instead went RF bravo and romeo. First officer was heads down with new checklist and international relief officer was helping. About half way to the runway; first officer realized we were in the wrong spot and asked ATC for a revised clearance; which they were fine with since we were the only airplane operating on the field at that hour.

Original NASA ASRS Text

Title: B757 Captain reported a taxiway incursion during taxi out due to fatigue; after a maintenance delay.

Narrative: Flight was air return due to airborne mechanical event. Upon taxi out; second time around; we were all tired from the air return plus being into our Window of Circadian Low (WOCL) on taxi out. ATC cleared us to taxi to 22L via RF; ALPHA and SIERRA. We instead went RF BRAVO and ROMEO. FO was heads down with new checklist and IRO was helping. About half way to the runway; FO realized we were in the wrong spot and asked ATC for a revised clearance; which they were fine with since we were the only airplane operating on the field at that hour.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Attributes
ACN	1291690
Time
Date	201508
Aircraft 1
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Taxi
Flight Plan	IFR
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 137 Flight Crew Total 4072 Flight Crew Type 1818
Events
Anomaly	Deviation - Procedural Clearance Ground Incursion Taxiway