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Unexplained deletion of FMS altitude restriction at fogog on honie RNAV STAR to atl results in altitude deviation for 737-700 flight crew.
| Attributes | |
| ACN | 776691 |
| Time | |
| Date | 200802 |
| Local Time Of Day | 1201 To 1800 |
| Place | |
| Locale Reference | airport : atl.airport |
| State Reference | GA |
| Altitude | msl single value : 11000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | tracon : a80.tracon tower : zzz.tower |
| Operator | common carrier : air carrier |
| Make Model Name | B737-700 |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | other |
| Flight Phase | descent : intermediate altitude |
| Route In Use | arrival star : honie |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| ASRS Report | 776691 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : atp |
| ASRS Report | 776690 |
| Events | |
| Anomaly | altitude deviation : crossing restriction not met altitude deviation : overshoot non adherence : clearance non adherence : published procedure |
| Independent Detector | other controllera |
| Resolutory Action | controller : issued new clearance controller : issued alert |
| Supplementary | |
| Problem Areas | Aircraft Flight Crew Human Performance |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
We were descending via the honie 4 RNAV arrival into atlanta. Both the PNF and I verified the crossing restrs in the CDU. I had the arrival plate out and available. The VNAV path indicator was showing high on the path; when ATC informed us to stop the descent and level off at 11000 ft. I quickly checked the legs page and saw the fogog altitude restr was gone; but the speed restr was still there. ATC informed us that there were no separation issues and to resume the descent after fogog. I believe the constraint was removed by an accidental additional push of the speed intervention button. Additionally these procedures are new. In the past ATC maintained your altitude until downwind and then descended you. Normal procedures are for the PF to monitor the VNAV page on the CDU. Monitoring the legs page on a RNAV arrival would provide greater situational awareness to the crossing restrs.
Original NASA ASRS Text
Title: UNEXPLAINED DELETION OF FMS ALT RESTRICTION AT FOGOG ON HONIE RNAV STAR TO ATL RESULTS IN ALT DEV FOR 737-700 FLT CREW.
Narrative: WE WERE DSNDING VIA THE HONIE 4 RNAV ARR INTO ATLANTA. BOTH THE PNF AND I VERIFIED THE XING RESTRS IN THE CDU. I HAD THE ARR PLATE OUT AND AVAILABLE. THE VNAV PATH INDICATOR WAS SHOWING HIGH ON THE PATH; WHEN ATC INFORMED US TO STOP THE DSCNT AND LEVEL OFF AT 11000 FT. I QUICKLY CHKED THE LEGS PAGE AND SAW THE FOGOG ALT RESTR WAS GONE; BUT THE SPD RESTR WAS STILL THERE. ATC INFORMED US THAT THERE WERE NO SEPARATION ISSUES AND TO RESUME THE DSCNT AFTER FOGOG. I BELIEVE THE CONSTRAINT WAS REMOVED BY AN ACCIDENTAL ADDITIONAL PUSH OF THE SPD INTERVENTION BUTTON. ADDITIONALLY THESE PROCS ARE NEW. IN THE PAST ATC MAINTAINED YOUR ALT UNTIL DOWNWIND AND THEN DSNDED YOU. NORMAL PROCS ARE FOR THE PF TO MONITOR THE VNAV PAGE ON THE CDU. MONITORING THE LEGS PAGE ON A RNAV ARR WOULD PROVIDE GREATER SITUATIONAL AWARENESS TO THE XING RESTRS.
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.