ACR MLG ALTDEV UNDERSHOT ALT XING RESTRICTION.

Narrative

FLT FROM LAX-IND. APCHING INDIANAPOLIS ON RNAV WITH CLRNC TO DSND TO 240 WITH XING RESTRICTION. DURING DSCNT COPLT DISCONNECTED AUTOPLT BECAUSE OF A STABILIZER OUT OF TRIM LIGHT AND MANUALLY LEVELED AT 240. I WENT OFF FREQ TO GET ATIS. WHEN I RETURNED; FO HAD REENGAGED AUTOPLT AND STATED CENTER HAD CLRED US TO 'CROSS 35 FROM INDIANAPOLIS AT 11000.' HE THEN PROGRAMMED THE FMC FOR THE XING RESTRICTION USING DOWN TRK FIX MODE FROM IND. SHORTLY THEREAFTER; DURING THE DSCNT; WE NOTICED THE DME TO THE XING FIX WAS MOVING FROM 35 TO 34; SO FO REPROGRAMMED IT AGAIN. CENTER INQUIRED IF WE WERE GOING TO MAKE THE XING RESTRICTION. THE FMC SHOWED US WELL WITHIN PARAMETERS ON BOTH DSCNT AND LEGS PAGES; SO I ASKED THE CENTER HOW FAR HE SHOWED US FROM THE XING FIX. HE STATED HE SHOWED US '35 MI FROM THE INDIANAPOLIS VOR.' WE WERE PASSING 18000 FT AT THAT TIME; AND I STATED WE COULD NOT MAKE IT; AND WE WERE TRACKING TO KIND (AS CLRED) VICE VHP. HE STATED THAT HE HAD CLRED US TO CROSS FROM VHP; AND TO DROP THE RESTRICTION. THE ACFT THEN BEGAN AN UNCOMMANDED L TURN; DURING WHICH THE CTLR ISSUED A CORRECTION TO MAKE A R 270 DEG TURN. AFTER WE LANDED; WE REALIZED THAT 2 THINGS OCCURRED. WE WERE GIVEN A VORTAC XING NOT COLOCATED WITH OUR ASSIGNED DEST; AND THE FO HAD INADVERTENTLY PLACED THE DOWN TRK FIX BEHIND; RATHER THAN IN FRONT OF; AN INTERIM FIX (KELLY); CAUSING AN APPROX 12-15 MI ERROR; AND ALSO THE UNCOMMAND TURN AS THE FMC ATTEMPTED TO RETURN TO XING FIX AFTER KELLY. THIS WAS CLRLY A CASE OF PLT OVERLOAD FOR THE FO; WITH NO BACKUP FROM ME AT A TIME WHEN IT WAS NEEDED. THE FO DID NOT HEAR THE CLRNC TO 'INDIANAPOLIS VOR'; AND SINCE VHP WAS NOT ON OUR FLT PLAN; HAD NO REASON TO ASSUME A XING RESTRICTION WOULD BE ISSUED FROM IT. I WAS NOT ON FREQ TO BACK HIM UP. WHEN I DID GET BACK; WE BECAME ABSORBED IN PROGRAMMING/REPROGRAMMING FMC; WHICH WAS PROGRAMMED INCORRECTLY; WHILE DOING ARR CHKLIST; DISCUSSING THE STABILIZER TRIM LIGHT; AND DISCUSSING THE APCH. IN RETROSPECT; THE PRUDENT ACTION WOULD HAVE BEEN FOR THE PNF (ME) TO GO TO A MANUAL BACKUP MODE; AND ALLOW THE PF TO HANDLE THE FMC CHORES (AUTOPLT ENGAGED). 2 HEADS BURIED IN THE FMC WAS NOT BETTER THAN 1; PARTICULARLY WHEN 1 (MINE) WAS NOT IN THE LOOP WHEN CLRNC ISSUED. IF VORTACS ARE NOT COLOCATED; DON'T ISSUE XING RESTRICTIONS FROM THEM UNLESS THEY ARE PART OF THE NAV PROCESS. BETTER STILL; CHANGE THE NAMES.