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Flight crew of an large transport undershot assigned crossing altitude due to relying on the FMC to descend the aircraft in time to meet the crossing restr.
| Attributes | |
| ACN | 431320 |
| Time | |
| Date | 199903 |
| Day | Thu |
| Local Time Of Day | 1201 To 1800 |
| Place | |
| Locale Reference | navaid : alb.vortac |
| State Reference | NY |
| Altitude | msl bound lower : 24000 msl bound upper : 27000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zbw.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | Commercial Fixed Wing |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | other vortac |
| Flight Phase | cruise : enroute altitude change |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 200 flight time total : 15000 flight time type : 200 |
| ASRS Report | 431320 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : commercial pilot : multi engine pilot : instrument technician : fcc |
| Events | |
| Anomaly | altitude deviation : crossing restriction not met altitude deviation : undershoot non adherence : clearance non adherence : far |
| Independent Detector | other flight crewa |
| Resolutory Action | none taken : anomaly accepted |
| Supplementary | |
| Problem Areas | Flight Crew Human Performance |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
We were given a crossing restr of FL240 25 mi northeast of alb VORTAC, descend at pilot's discretion to meet the restr. The FMC was programmed to meet the restr. As we were about to reach the descent point (approximately 2 NM) ATC asked to begin descent now. Descent now was selected on the FMC. The aircraft began its descent and the crossing looked good on the display. I began to prepare for arrival. I was distraction from the profile display with several operational problems. I failed to monitor the PF's efforts to manage his descent. I did not maintain situational awareness. We missed the crossing restr by 3000 ft. Nothing was said by ATC. There were no traffic conflicts. I still do not know why the FMC did not meet the profile. I assume the 1200 FPM descent rate from descend now never intercepted the programmed profile for the crossing restr. Chalk this up to FMC complacency and failure to monitor the PF (first officer, FMC).
Original NASA ASRS Text
Title: FLC OF AN LGT UNDERSHOT ASSIGNED XING ALT DUE TO RELYING ON THE FMC TO DSND THE ACFT IN TIME TO MEET THE XING RESTR.
Narrative: WE WERE GIVEN A XING RESTR OF FL240 25 MI NE OF ALB VORTAC, DSND AT PLT'S DISCRETION TO MEET THE RESTR. THE FMC WAS PROGRAMMED TO MEET THE RESTR. AS WE WERE ABOUT TO REACH THE DSCNT POINT (APPROX 2 NM) ATC ASKED TO BEGIN DSCNT NOW. DSCNT NOW WAS SELECTED ON THE FMC. THE ACFT BEGAN ITS DSCNT AND THE XING LOOKED GOOD ON THE DISPLAY. I BEGAN TO PREPARE FOR ARR. I WAS DISTR FROM THE PROFILE DISPLAY WITH SEVERAL OPERATIONAL PROBS. I FAILED TO MONITOR THE PF'S EFFORTS TO MANAGE HIS DSCNT. I DID NOT MAINTAIN SITUATIONAL AWARENESS. WE MISSED THE XING RESTR BY 3000 FT. NOTHING WAS SAID BY ATC. THERE WERE NO TFC CONFLICTS. I STILL DO NOT KNOW WHY THE FMC DID NOT MEET THE PROFILE. I ASSUME THE 1200 FPM DSCNT RATE FROM DSND NOW NEVER INTERCEPTED THE PROGRAMMED PROFILE FOR THE XING RESTR. CHALK THIS UP TO FMC COMPLACENCY AND FAILURE TO MONITOR THE PF (FO, FMC).
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.