AN ACR MLG CREW FAILED TO NOTE THE CHANGES IN ITS AIRWAYS ROUTING FROM PDC.

Narrative

DURING PREFLT; I ENTERED THE FILED ROUTING INTO THE FMC. WHEN CLRNC WAS RECEIVED VIA ACARS; 2 ROUTINGS APPEARED. THE FIRST SHOWED A SOMEWHAT DIFFERENT ROUTING TO TCC. THE SECOND; AND LAST; SHOWED AS FILED. WE INTERPRETED THIS TO MEAN THAT THE FILED COURSE WAS THE CURRENT COURSE; WHEN; IN FACT; THE REVERSE WAS TRUE. NOT UNTIL ABQ; WERE WE QUESTIONED BY CTR REGARDING OUR RTE. WE CARRIED THE DISCUSSION TO THE NEXT SECTOR; WHO DIDN'T THINK IT CREATED A PROB; AND HE CLRED US DIRECTLY TO FAM. RESEARCHING THE FLT OPS MANUAL REVEALED THAT WHEN 2 CLRNCS APPEAR ON ACARS; THE CURRENT CLRNC IS THE TOP CLRNC. IT AMENDS WHAT IS BELOW. A LIFETIME OF READING WORDS TYPED ON PAPER INSTILLS IN MOST OF US THAT THE LAST MESSAGE TYPED IS THE MOST CURRENT. COMPUTER GENERATED MESSAGES DISPLAYED ON A SCREEN ARE NOT BOUND BY MECHANICALLY TYPED FORMATS. PERHAPS A BULLETIN HIGHLIGHTING THIS ACARS FEATURE WOULD PREVENT FUTURE OCCURRENCES. OF COURSE; A SIMPLE 'AMENDED ROUTING' ALERT PRIOR TO THE ROUTING DISPLAY WOULD TOTALLY SOLVE THE PROB. ROUTINGS ARE TOO IMPORTANT TO BE DISPLAYED CRYPTICALLY. SUPPLEMENTAL INFO FROM ACN 247586: WE HAD RECEIVED OUR RTE CLRNC FROM PHX CLRNC VIA PDC PROCS ON OUR ACARS SYS AND HAD NOT VERBALLY TALKED TO CLRNC DELIVERY. THE ACARS SCREEN SHOWED 2 CLRNCS TO TCC; THE FIRST BEING THE RTE THAT ATC EXPECTED US TO BE FLYING; AND THE SECOND (WHICH MATCHED OUR FILED RTE) THE ONE WE ASSUMED WAS THE CORRECT ROUTING. WE HAD DECIDED THAT THE AMENDED ROUTING WAS A COMPUTER MISPRINT AND THAT THE ORIGINAL FLT PLAN THAT WAS PRINTED BELOW WAS THE CORRECT CLRNC.