MLG FLIES WRONG SID ON DEP.

Narrative

THE FLT I WAS IN COMMAND OF DEPARTED ANC'S RWY 6L WITH MY FO AT THE CTLS. WE HAD BEEN ASSIGNED THE ANC1 DEP WHICH CALLED FOR A TURN FROM RWY HDG TO THE S AT 2000 FT OR 9 DME ANC VOR; WHICHEVER OCCURS FIRST. THE DEP WE ACTUALLY FLEW WAS THE KNIK4. THIS IS THE DEP WE HAD PERFORMED EARLIER IN THE DAY; AND ALSO; THE ASSIGNED DEP THE ACFT WE WERE FOLLOWING HAD JUST PERFORMED AS WE WATCHED. THE KNIK4 CALLS FOR A TURN FROM RWY HDG TO THE N AT 2000 FT OR 11 DME ANC VOR WHICHEVER OCCURS FIRST. OUR COMPANY POLICY CALLS TO USE A NOISE ABATEMENT PROFILE FOR DEPS OFF OF ANC'S E RWYS. THE PROFILE IN ANC DIFFERED SLIGHTLY THAN THE STANDARD PROFILE SINCE IT CALLED TO REDUCE THE PWR TO THE 'NOISE PWR' SETTING AT 2000 FT INSTEAD OF THE ORIGINAL 1000 FT. (NOTE: 2000 FT; SAME PLACE ON BOTH ANC1 AND KNIK4 WHERE THE TURN AS INITIATED.) SINCE I WAS THE PNF MY DUTY WAS TO SET THE 'NOISE PWR' SETTING WHEN CALLED FOR; A 'HEADS DOWN TASK.' UPON COMPLETING THE TASK AND VISUALLY BRINGING MYSELF OUT OF THE COCKPIT I NOTICED WE WERE IN A L TURN AND NOT A R TURN AS OUR ASSIGNED DEP CALLED FOR. I QUERIED MY FO AS TO WHETHER THE TURN SHOULD BE TO THE R; HE CONTINUED L. AT THIS POINT WE BOTH WERE SOMEWHAT PUZZLED. IT HAD BEEN QUITE SOME TIME SINCE THE FO HAD PERFORMED HIS TKOF BRIEF; BECAUSE OF A LINE UP PRIOR TO DEP AND ALSO BECAUSE THE SIDS FOR ANC BOTH THE KNIK4 AND ANC1 READ IDENTICAL FOR ALL RWYS EXCEPT 6R AND 6L. WITHOUT ANY CONFLICT ANC DEP CTL NOTIFIED US OF OUR BLUNDER AND GOT US GOING IN THE RIGHT DIRECTION MOST CORDIALLY. CONTRIBUTING FACTORS: HAVING A TKOF BRIEFING FRESH IN YOUR MIND; TIME EXPIRED BTWN THE FO PERFORMING HIS BRIEFING AND THE DEP. ALERTNESS OF CREW. AT THE TIME OF THE EVENT WE HAD BOTH BEEN ON DUTY FOR 7 HRS. NO A GREAT DEAL OF TIME BUT OUR FIRST RPT TO THE COMPANY DURING THIS DUTY PERIOD WAS AT EARLY MORNING. FOR MYSELF; I AM A RESERVE CAPT WHO IS ON A 24 HR A DAY STANDBY STATUS. THIS TYPE OF SCHEDULING DOES NOT LEND ITSELF TO A STRUCTURED REST CYCLE. THEREFORE; IT OFTEN REQUIRES ME TO AWAKE FOR A TRIP AT THE SAME TIME OF DAY I MIGHT HAVE COMPLETED ONE WITHIN THE SAME 24 HR PERIOD. (POOR AND UNSAFE SCHEDULING PRACTICES.) MONKEY SEE; MONKEY DO. WE WATCHED THE TFC AHEAD OF US DEPART OFF OF THE E RWY AND MAKE A L TURN; SO WE DID JUST THAT.