 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
A B737-800 missed compulsory STAR altitude because the FMS database in use was not yet active and displayed future restrictions; not current ones.
| Attributes | |
| ACN | 772866 |
| Time | |
| Date | 200802 |
| Place | |
| Locale Reference | airport : sea.airport |
| State Reference | WA |
| Altitude | msl single value : 18000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zse.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | B737-800 |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | other |
| Flight Phase | descent : intermediate altitude |
| Route In Use | arrival star : chins |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Experience | flight time last 90 days : 200 flight time type : 1000 |
| ASRS Report | 772866 |
| Person 2 | |
| Affiliation | government : faa |
| Function | controller : radar |
| Events | |
| Anomaly | altitude deviation : crossing restriction not met non adherence : published procedure non adherence : company policies non adherence : clearance |
| Independent Detector | other controllera other flight crewa |
| Resolutory Action | none taken : detected after the fact |
| Consequence | faa : reviewed incident with flight crew |
| Supplementary | |
| Problem Areas | Maintenance Human Performance Flight Crew Human Performance |
| Primary Problem | Flight Crew Human Performance |
Narrative:
Maintenance performed database download the previous night. During FMS/CDU preflight; did not notice that databases were 'swapped;' ie; a database from next week was active in the FMC. Did not notice that 'chins 6' arrival loaded; instead of 'chins 5.' when briefing chins 5 arrival; did not notice that the FMC altitude for raddy intersection was '16000A' when it should have been '16000.' we got the altitude right; but missed the letter after the altitude. ATC pointed out that we 'were blowing off' altitude at raddy; and asked if we would make the 15000 ft or below restr at humpp intersection. Just before ATC had called; we noticed that we were high crossing raddy; and had increased our rate of descent. We crossed raddy high; perhaps at FL180. We easily made the restr at humpp. ATC said nothing else after the incident. This was a 'swiss cheese' type of error. We had numerous chances to catch the error (preflight; route loading; descent/approach briefing) but still didn't catch the error. We trusted the automation; and the automation performed the chins 6 perfectly; but we were cleared the chins 5. This is a good wake-up call for me to be more careful during FMC preflight programming and during the descent briefing; and then to monitor aircraft performance as if we had 'no' automation. This event will re-install my mistrust of automation. Statement above covers these thoughts. Maintenance might be reminded to re-select the current database after a download; but the final responsibility rests with the flight crew.
Original NASA ASRS Text
Title: A B737-800 MISSED COMPULSORY STAR ALT BECAUSE THE FMS DATABASE IN USE WAS NOT YET ACTIVE AND DISPLAYED FUTURE RESTRICTIONS; NOT CURRENT ONES.
Narrative: MAINT PERFORMED DATABASE DOWNLOAD THE PREVIOUS NIGHT. DURING FMS/CDU PREFLT; DID NOT NOTICE THAT DATABASES WERE 'SWAPPED;' IE; A DATABASE FROM NEXT WK WAS ACTIVE IN THE FMC. DID NOT NOTICE THAT 'CHINS 6' ARR LOADED; INSTEAD OF 'CHINS 5.' WHEN BRIEFING CHINS 5 ARR; DID NOT NOTICE THAT THE FMC ALT FOR RADDY INTXN WAS '16000A' WHEN IT SHOULD HAVE BEEN '16000.' WE GOT THE ALT RIGHT; BUT MISSED THE LETTER AFTER THE ALT. ATC POINTED OUT THAT WE 'WERE BLOWING OFF' ALT AT RADDY; AND ASKED IF WE WOULD MAKE THE 15000 FT OR BELOW RESTR AT HUMPP INTXN. JUST BEFORE ATC HAD CALLED; WE NOTICED THAT WE WERE HIGH XING RADDY; AND HAD INCREASED OUR RATE OF DSCNT. WE CROSSED RADDY HIGH; PERHAPS AT FL180. WE EASILY MADE THE RESTR AT HUMPP. ATC SAID NOTHING ELSE AFTER THE INCIDENT. THIS WAS A 'SWISS CHEESE' TYPE OF ERROR. WE HAD NUMEROUS CHANCES TO CATCH THE ERROR (PREFLT; RTE LOADING; DSCNT/APCH BRIEFING) BUT STILL DIDN'T CATCH THE ERROR. WE TRUSTED THE AUTOMATION; AND THE AUTOMATION PERFORMED THE CHINS 6 PERFECTLY; BUT WE WERE CLRED THE CHINS 5. THIS IS A GOOD WAKE-UP CALL FOR ME TO BE MORE CAREFUL DURING FMC PREFLT PROGRAMMING AND DURING THE DSCNT BRIEFING; AND THEN TO MONITOR ACFT PERFORMANCE AS IF WE HAD 'NO' AUTOMATION. THIS EVENT WILL RE-INSTALL MY MISTRUST OF AUTOMATION. STATEMENT ABOVE COVERS THESE THOUGHTS. MAINT MIGHT BE REMINDED TO RE-SELECT THE CURRENT DATABASE AFTER A DOWNLOAD; BUT THE FINAL RESPONSIBILITY RESTS WITH THE FLT CREW.
Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.