B737 CAPT DETAILS THE COMPLICATIONS ASSOCIATED WITH FMS SOFTWARE UPGRADES AND DIFFERENCE BETWEEN SOFTWARE DATA AND PUBLISHED PROCEDURES.

Date: 2008-05 · Aircraft: B737 Undifferentiated or Other Model · Phase: approach

Anomalies: aircraft-equipment-problem-less-severe|other-fms-software

Synopsis

B737 CAPT DETAILS THE COMPLICATIONS ASSOCIATED WITH FMS SOFTWARE UPGRADES AND DIFFERENCE BETWEEN SOFTWARE DATA AND PUBLISHED PROCEDURES.

Narrative

DUE TO THE NEW SOFTWARE UPDATE THAT REQUIRES YOU TO CHANGE ALTS; SO THAT THEY COMPLY WITH THE CHARTED VALUES; THE ACFT AND CREW CAN EASILY MAKE MISTAKES; IE; CHANGING THE SPD AT EDDNA TO 210 KTS AT 8000K INSTEAD OF WHAT COMES UP IN THE BOX 210B AND 8000B. IN THIS CASE A SLIGHT DEV IN ALT OCCURRED. THE ACFT STARTED DOWN A LITTLE EARLY BEFORE EDDNA THUS XING IT AT 7800 FT IN ORDER TO MAKE KUCOO AT 6000 FT. ALT HOLD WAS PRESSED; BUT BY THAT TIME WE CAPTURED EDDNA. THE BOTTOM LINE IS THAT WE SHOULD NOT HAVE TO RE-INPUT ALL THE ALTS AND SPDS BECAUSE OF THE SOFTWARE CHANGE. I HAVE ALSO NOTICED THAT WHEN ATC REQUESTS A LOWER SPD AT A LOCATION; IE; 250 KTS AT RADDY INTO SEA VICE 280 KTS; THE MCDU WILL NOT ACCEPT IT UNLESS YOU CHANGE EVERY OTHER POINT TO THAT POINT WITH THE UPDATED SPD; AND THE DSCNT SPD ALSO. THIS NEVER USED TO BE AN ISSUE. YOU WERE JUST ABLE TO PLUG IN THE SPD IN THE BOX; AND IT WOULD LET YOU. NOW BOTH PLTS COULD BE HEADS DOWN STRUGGLING TO UNDERSTAND WHY THE BOX WILL NOT ACCEPT THE INPUT. IT SEEMS AS THOUGH THE NEW UPDATE HAS ADDED MORE WORK WITH AUTOMATION WHICH CAN LEAD TO ERRORS.

More incidents for this aircraft family →

Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.