RWY INCURSION.

Narrative

ON THE LAST LEG OF THE DAY WHILE TAXIING TO THE ACTIVE RWY AT NIGHT IN ATHENS; GA; I CROSSED THE HOLD SHORT LINE WITHOUT CLRNC AND ENDED UP ON THE ACTIVE RWY. THIS WAS IMMEDIATELY NOTICED BY MYSELF; THE OTHER PLT AND THE GND CTLR. HE CLRED US ONTO THE RWY; CLRED US FOR TKOF; AND WE DEPARTED WITHOUT INCIDENT. THE REST OF THE FLT WAS UNEVENTFUL. ALTHOUGH THE INCIDENT WAS WITHOUT CONFLICT THE POTENTIAL FOR DISASTER WAS CLR. THE INACTION OF MYSELF TO BECOME MORE FAMILIAR WITH ARPT BY CLOSER USE OF THE ARPT DIAGRAM WAS A MAJOR FACTOR. ANOTHER MAJOR FACTOR WAS FATIGUE. I FELT TIRED ENOUGH TO TAKE A 15 MIN 'CAT NAP' AN HR BEFORE DEP. OBVIOUSLY THIS WAS NOT ENOUGH. THE FACT THAT IT WAS AFTER DARK WAS ALSO A CONTRIBUTING FACTOR. SUPPLEMENTAL INFO FROM ACN 301649: AS WE NEARED RWY 27; I WAS IN THE PROCESS OF SETTING THE V SPD INTO THE PRIMARY FLT DISPLAYS. I DID NOT NOTICE THAT HE HAD FAILED TO STOP AT THE RWY HOLD SHORT LINE FOR RWY 27. HE PROCEEDED ON TO THE RWY WITHOUT CLRNC. AS THE TWR CAUGHT OUR MISTAKE I LOOKED UP TO SEE US ON THE RWY. I ASKED HIM IF HE HAD LOOKED AT THE DIAGRAM AND HE SAID HE HAD IGNORED IT. IT WAS HIS FIRST TIME AT THIS LOCATION AND IT WAS LATE AT NIGHT. HE SAID THE NEXT MORNING THAT HE WAS VERY FATIGUED; MORE THAN HE THOUGHT AT THE TIME OF THE OCCURRENCE. OUR FLYING DAY STARTED AT T47 AT XA30 LCL. IF UNFAMILIAR; EXERCISE EXTREME CAUTION AND LOOK AT ARPT DIAGRAM.