FATIGUED MD80 FLT CREW; AFTER A LENGTHY GND DELAY; FAILS TO UPDATE DEP RWY WHILE FLYING RNAV SID FROM DFW. TRACK DEV ENSUES.

Narrative

WE DEPARTED DFW RWY 36R WITH RWY 35L INCORRECTLY LOADED IN THE FMS. FOLLOWING A NORMAL ROTATION AND GEAR RETRACTION; THE NAV MODE WAS SELECTED AT 400 FT AGL. THE V-BARS COMMANDED APPROX 3 DEGS R ANGLE OF BANK. I; THE PF; FOLLOWED THEM PRECISELY. AS THE FO AND I OBSERVED THE POS OF AN ACFT 2.5 NM AHEAD AT 1 O'CLOCK POS; WE BOTH REALIZED OUR ERROR. I EXECUTED AN IMMEDIATE L TURN TO CORRECT AND INTERCEPT THE APPROPRIATE DEP COURSE. DEP QUERIED US AND WE ADVISED THAT WE WERE CORRECTING OUR COURSE. MY FO REQUESTED 'DIRECT HAZKL' AND DEP GRANTED THE REQUEST. AS WE WERE VISUALLY PREOCCUPIED WITH THE ACFT AHEAD; APPARENTLY LOSS OF SEPARATION OCCURRED WITH AN ACFT BEHIND US -- ACCORDING TO A LATER CONVERSATION WITH AN ATC SUPVR VIA PHONE AFTER THE FLT. THE SUPVR ASKED FOR MY PERSONAL INFO -- WHICH I PROVIDED. I HAVE NO EXCUSE FOR THIS ERROR. THE FO DIDN'T UPDATE THE FMS DEP RWY AND I FAILED TO FOLLOW UP. I WOULD LIKE TO SUBMIT WHAT MIGHT BE A CONSIDERED CONTRIBUTING FACTOR TO THIS ERROR AND ONE SUGGESTION FOR IMPROVEMENT IN STANDARD PROCS. WE HAD EXPERIENCED 2 ATC FLOW CTL DELAYS PRIOR TO DEP. JUST AS WE PRACTICE DURING DEICING DELAYS; WE SHOULD HAVE REVISITED THE MECHANICAL CHKLIST ITEM 'FLT INSTS AND BUGS' AS WELL AS ALL OTHER MECHANICAL CHKLIST ITEMS. MY NAV DISPLAY WAS SET AT 5 NM TO CONFIRM CORRECT TRACKING OF THE RNAV COURSE; BUT THAT PREVENTED ME FROM SEEING THE WAYPOINTS OF THE ENTIRE RNAV PROC WHICH WOULD HAVE ALERTED ME TO THE INCORRECT FMS PROGRAMMING. THIS WAS OUR FIRST LEG OF A 3-DAY SEQUENCE TOGETHER. THIS WAS MY 4TH OF 6 STRAIGHT DAYS OF FLYING. I HAD BEEN AWAKE FOR 12 HRS AND HAD BEEN THROUGH 3 HRS OF ATC DELAYS. ACTUAL DEP TIME; NOW XA00; WAS MUCH LATER THAN PLANNED. I SHOULD HAVE 'TWEAKED' UP MY AWARENESS LEVEL A FEW NOTCHES KNOWING THAT THESE FACTORS MIGHT CONTRIBUTE TO MISTAKES. AS MORE AND MORE STATIONS ADOPT RNAV DEP PROCS; THE POSSIBILITY OF THIS ERROR OCCURRING IN THE FUTURE WILL ONLY INCREASE.