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Captain of an airbus 321 overshot intermediate STAR altitude fix due to being distraction by traffic watch, reprogramming FMS with new runway assignment and needing to expedite descent just prior to the required altitude fix.
| Attributes | |
| ACN | 515331 |
| Time | |
| Date | 200106 |
| Day | Sat |
| Place | |
| Locale Reference | intersection : mitts |
| State Reference | CA |
| Altitude | msl bound lower : 9000 msl bound upper : 10000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | tracon : sct.tracon |
| Operator | common carrier : air carrier |
| Make Model Name | A321 |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | other |
| Flight Phase | descent : approach |
| Route In Use | arrival star : mitts1 |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : flight engineer pilot : commercial pilot : atp |
| Experience | flight time last 90 days : 150 flight time total : 13500 flight time type : 200 |
| ASRS Report | 515331 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Events | |
| Anomaly | altitude deviation : crossing restriction not met altitude deviation : overshoot non adherence : clearance non adherence : published procedure |
| Independent Detector | other flight crewa |
| Resolutory Action | none taken : anomaly accepted |
| Supplementary | |
| Problem Areas | Flight Crew Human Performance ATC Human Performance |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
Operating an airbus 321 into lax, on the mitts 1 arrival, we were cleared to descend on the profile and cross 'at or above' all fixes. As we were high on the profile to the runway (runway 24R) the aircraft was in an idle descent with speed brakes extended. Just prior to crossing the mitts intersection, we passed through 10000 ft and leveled off at 9000 ft until jonzz intersection. After joining the final approach course, a normal landing was made. My estimation of the cause of the crossing altitude error at mitts was the initial need to expedite descent to cross civet intersection at 14000 ft. High workload looking for traffic as well as reprogramming runway. Assignment into FMC coupled with failure to resume normal descent rate contributed to the missed altitude. Had the initial STAR been left unchanged, and lower altitudes been given in a timely manner, workload would be vastly reduced, thereby fostering more vigilance by the flight crew. As we all know, the advanced flight deck and FMC such as the airbus has, can only reduce workload and increase safety if it is allowed to do so by leaving the flight plan as was programmed at preflight unaltered. Lax and socal approach have a well earned, industry-wide reputation for multiple STAR/SID and approach/runway changes. With so much traffic in this corridor, it is much safer to maintain separation than to be 'heads down' making ATC revisions to the flight plan.
Original NASA ASRS Text
Title: CAPT OF AN AIRBUS 321 OVERSHOT INTERMEDIATE STAR ALT FIX DUE TO BEING DISTR BY TFC WATCH, REPROGRAMMING FMS WITH NEW RWY ASSIGNMENT AND NEEDING TO EXPEDITE DSCNT JUST PRIOR TO THE REQUIRED ALT FIX.
Narrative: OPERATING AN AIRBUS 321 INTO LAX, ON THE MITTS 1 ARR, WE WERE CLRED TO DSND ON THE PROFILE AND CROSS 'AT OR ABOVE' ALL FIXES. AS WE WERE HIGH ON THE PROFILE TO THE RWY (RWY 24R) THE ACFT WAS IN AN IDLE DSCNT WITH SPD BRAKES EXTENDED. JUST PRIOR TO XING THE MITTS INTXN, WE PASSED THROUGH 10000 FT AND LEVELED OFF AT 9000 FT UNTIL JONZZ INTXN. AFTER JOINING THE FINAL APCH COURSE, A NORMAL LNDG WAS MADE. MY ESTIMATION OF THE CAUSE OF THE XING ALT ERROR AT MITTS WAS THE INITIAL NEED TO EXPEDITE DSCNT TO CROSS CIVET INTXN AT 14000 FT. HIGH WORKLOAD LOOKING FOR TFC AS WELL AS REPROGRAMMING RWY. ASSIGNMENT INTO FMC COUPLED WITH FAILURE TO RESUME NORMAL DSCNT RATE CONTRIBUTED TO THE MISSED ALT. HAD THE INITIAL STAR BEEN LEFT UNCHANGED, AND LOWER ALTS BEEN GIVEN IN A TIMELY MANNER, WORKLOAD WOULD BE VASTLY REDUCED, THEREBY FOSTERING MORE VIGILANCE BY THE FLC. AS WE ALL KNOW, THE ADVANCED FLT DECK AND FMC SUCH AS THE AIRBUS HAS, CAN ONLY REDUCE WORKLOAD AND INCREASE SAFETY IF IT IS ALLOWED TO DO SO BY LEAVING THE FLT PLAN AS WAS PROGRAMMED AT PREFLT UNALTERED. LAX AND SOCAL APCH HAVE A WELL EARNED, INDUSTRY-WIDE REPUTATION FOR MULTIPLE STAR/SID AND APCH/RWY CHANGES. WITH SO MUCH TFC IN THIS CORRIDOR, IT IS MUCH SAFER TO MAINTAIN SEPARATION THAN TO BE 'HEADS DOWN' MAKING ATC REVISIONS TO THE FLT PLAN.
Data retrieved from NASA's ASRS site as of July 2007 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.