 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
Air carrier flight crew fails to catch dropped waypoint from FMS. A very minor track deviation results.
| Attributes | |
| ACN | 462100 |
| Time | |
| Date | 200001 |
| Day | Sun |
| Local Time Of Day | 1201 To 1800 |
| Place | |
| Locale Reference | atc facility : zla.artcc |
| State Reference | CA |
| Environment | |
| Flight Conditions | Mixed |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zla.artcc tower : lou.tower |
| Operator | common carrier : air carrier |
| Make Model Name | Large Transport, Low Wing, 2 Turbojet Eng |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | other |
| Flight Phase | cruise : level |
| Route In Use | enroute : direct |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : commercial pilot : private pilot : multi engine pilot : instrument pilot : atp |
| Experience | flight time last 90 days : 120 flight time total : 13600 flight time type : 65 |
| ASRS Report | 462100 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Events | |
| Anomaly | non adherence : clearance other spatial deviation |
| Independent Detector | other controllera other flight crewa other flight crewb |
| Resolutory Action | controller : issued advisory flight crew : returned to intended or assigned course |
| Supplementary | |
| Problem Areas | Flight Crew Human Performance Aircraft |
| Primary Problem | Flight Crew Human Performance |
Narrative:
Original clearance in sfo issued as filed to lax then T1J then direct mex. We questioned this as unusual, controller verified. Captain programmed 'discontinuity' after lax to ensure we verified clearance before lax. Prior to lax we were reclred after lax as filed lax jli J93 ppe hwd UJ5. We were then cleared direct jli, while the captain (PNF) reprogrammed for reroute. I selected direct jli from existing flight plan information and verified. Some time after, ATC asked to verify we were direct jli. We looked to see we were direct downline NAVAID. I believe it was ptj. We informed ATC we were not direct jli. ATC reclred us direct jli. The correction was small as I believe we were about 1 mi off the lax-jli track. What was most disturbing was not being sure how it had happened. We believe it happened by clearing a discontinuity near 'bottom' of flight plan before clearing discontinuity at top of flight plan which in this aircraft can cause all of flight plan above second discontinuity to be erased. It is also possible that mcdu was calculating as I entered the direct input. In some cases this aircraft will 'jump' to another point in flight plan as you enter information, causing incorrect input. I was new in aircraft and still not completely 'converted' from another air carrier information. Being on smaller scale on navigation display and verifying to point on navigation display would have prevented this. In an attempt to comply quickly to clearance, both of us entered information in computer at the same time, taking away some ability to back each other up.
Original NASA ASRS Text
Title: ACR FLC FAILS TO CATCH DROPPED WAYPOINT FROM FMS. A VERY MINOR TRACK DEV RESULTS.
Narrative: ORIGINAL CLRNC IN SFO ISSUED AS FILED TO LAX THEN T1J THEN DIRECT MEX. WE QUESTIONED THIS AS UNUSUAL, CTLR VERIFIED. CAPT PROGRAMMED 'DISCONTINUITY' AFTER LAX TO ENSURE WE VERIFIED CLRNC BEFORE LAX. PRIOR TO LAX WE WERE RECLRED AFTER LAX AS FILED LAX JLI J93 PPE HWD UJ5. WE WERE THEN CLRED DIRECT JLI, WHILE THE CAPT (PNF) REPROGRAMMED FOR REROUTE. I SELECTED DIRECT JLI FROM EXISTING FLT PLAN INFO AND VERIFIED. SOME TIME AFTER, ATC ASKED TO VERIFY WE WERE DIRECT JLI. WE LOOKED TO SEE WE WERE DIRECT DOWNLINE NAVAID. I BELIEVE IT WAS PTJ. WE INFORMED ATC WE WERE NOT DIRECT JLI. ATC RECLRED US DIRECT JLI. THE CORRECTION WAS SMALL AS I BELIEVE WE WERE ABOUT 1 MI OFF THE LAX-JLI TRACK. WHAT WAS MOST DISTURBING WAS NOT BEING SURE HOW IT HAD HAPPENED. WE BELIEVE IT HAPPENED BY CLRING A DISCONTINUITY NEAR 'BOTTOM' OF FLT PLAN BEFORE CLRING DISCONTINUITY AT TOP OF FLT PLAN WHICH IN THIS ACFT CAN CAUSE ALL OF FLT PLAN ABOVE SECOND DISCONTINUITY TO BE ERASED. IT IS ALSO POSSIBLE THAT MCDU WAS CALCULATING AS I ENTERED THE DIRECT INPUT. IN SOME CASES THIS ACFT WILL 'JUMP' TO ANOTHER POINT IN FLT PLAN AS YOU ENTER INFO, CAUSING INCORRECT INPUT. I WAS NEW IN ACFT AND STILL NOT COMPLETELY 'CONVERTED' FROM ANOTHER ACR INFO. BEING ON SMALLER SCALE ON NAV DISPLAY AND VERIFYING TO POINT ON NAV DISPLAY WOULD HAVE PREVENTED THIS. IN AN ATTEMPT TO COMPLY QUICKLY TO CLRNC, BOTH OF US ENTERED INFO IN COMPUTER AT THE SAME TIME, TAKING AWAY SOME ABILITY TO BACK EACH OTHER UP.
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.