ADVANCED AUTOMATED COCKPIT MGMNT.

Narrative

RECEIVED CLRNC FROM ZDC TO 'CROSS 35 SW OF ELKINS AT 240.' FO (FLYING) ATTEMPTED TO DO THIS ON THE FMC BY LOOKING AT THE FMC (ASBUR; BOGGE; ROCKA; OAKLE; PERRI; PERKS) FINDING THE CLOSEST TO 35 AND ATTEMPTING AN OFFSET FIX; ENTERING IT; DETERMINING XING ALT; ENTERING IT AND EXECUTING A VNAV DSCNT. I WAS ASSUMING HE WAS MERELY PICKING A FIX (PERRI) THAT WOULD MEET THE REQUIREMENTS AND EXECUTING A DSCNT TO FL240 AT THAT POINT. AFTER NUMEROUS ATTEMPTS TO UNSUCCESSFULLY ACCOMPLISH THIS; THE FO STARTED A SLOW DSCNT AND RETURNED TO THE FMC; APPARENTLY OBSESSED ABOUT ACCOMPLISHING HIS TASK. WHEN I REALIZED HE WAS 1) NOT DOING WHAT I THOUGHT HE WAS DOING; AND 2) HAD THE FMC PANEL IN A STATE THAT WAS NOT NAVIGABLE. I CALLED THE FIX PAGE UP AND ENTERED ELKINS. WE WERE AT THAT TIME XING THE POINT SPECIFIED AND WERE 2000 FT HIGH. I CALLED CTR; APOLOGIZED AND MAXIMIZED DSCNT. I ALSO UPBRAIDED MYSELF FOR NOT IMMEDIATELY GOING TO THE FIX PAGE AND BACKING UP THE DSCNT WITH A MENTAL CALCULATION. AS A MORE 'MATURE' PLT; I AM SEEING MORE AND MORE OF THIS SCENARIO; I.E.; A FAIRLY GOOD PLT TURNS INTO A 'COMPUTER NERD' WHEN GIVEN A NON STANDARD CLRNC OR XING RESTR; AND BECOMES COMPLETELY FASCINATED/CHALLENGED/ ABSORBED WITH PUTTING IT IN THE FMC AT THE EXPENSE OF COMMON SENSE; AND IN THIS CASE A FLT PROFILE MEETING ATC CLRNC. ATTEMPTING AN OFFSET FIX IS PROBLEMATIC AT BEST; BUT IMPOSSIBLE AT THE TIME FRAME WE HAD. MY ERRORS WERE ASSUMING HE WAS SIMPLY PUTTING IN FL240 AT PERRI; AND NOT CALLING UP ELKINS OF THE FIX PAGE AS A BACKUP. THE BOTTOM LINE FOR 'COMPUTER NERDS' PLTING AN ACFT -- UNLIKE YOUR HOME COMPUTER TIME AND THE ACFT DON'T STOP WHEN YOU HAVE AN INPUT PROB.