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Improper entry of pbi vice fll into the IRS for alignment results in a navigation error that was not discovered until midway to destination because initial routing involved many vectors around convective WX.
| Attributes | |
| ACN | 629951 |
| Time | |
| Date | 200408 |
| Day | Tue |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | navaid : chs.vortac |
| State Reference | SC |
| Altitude | msl single value : 33000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zjx.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | B757 Undifferentiated or Other Model |
| Operating Under FAR Part | Part 121 |
| Flight Phase | cruise : level |
| Route In Use | enroute : on vectors |
| 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 : 18000 flight time type : 3600 |
| ASRS Report | 629951 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Events | |
| Anomaly | non adherence : published procedure other spatial deviation |
| Independent Detector | other flight crewa |
| Resolutory Action | controller : issued new clearance flight crew : became reoriented other |
| Supplementary | |
| Problem Areas | Flight Crew Human Performance |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
I flew 9 times out of pbi until this last trip this month out of fll. As part of preflight, my first officer turned IRS's off then back on, to align them. Did exterior walkaround. After 10 mins, I began FMS loading and IRS alignment and noticed align lights flashing due to no position entered within 10 mins. I turned IRS's off then back to align (lights steady) then erroneously entered pbi coordinates instead of fll. Our training states you need to enter a new position 3 times if significantly different from shutdown position. This alignment took only 1 incorrect position entry to enter and complete alignment. This resulted in a 37 mi position error which lasted the entire flight from fll. After takeoff we were on radar vectors and heading deviations due to WX till approaching chs VOR. This is where we discovered the navigation error and then advised ATC of our FMS navigation error. Since the heading from fll to pbi is approximately the same as our route of flight, we probably were not very far off course laterally.
Original NASA ASRS Text
Title: IMPROPER ENTRY OF PBI VICE FLL INTO THE IRS FOR ALIGNMENT RESULTS IN A NAV ERROR THAT WAS NOT DISCOVERED UNTIL MIDWAY TO DEST BECAUSE INITIAL ROUTING INVOLVED MANY VECTORS AROUND CONVECTIVE WX.
Narrative: I FLEW 9 TIMES OUT OF PBI UNTIL THIS LAST TRIP THIS MONTH OUT OF FLL. AS PART OF PREFLT, MY FO TURNED IRS'S OFF THEN BACK ON, TO ALIGN THEM. DID EXTERIOR WALKAROUND. AFTER 10 MINS, I BEGAN FMS LOADING AND IRS ALIGNMENT AND NOTICED ALIGN LIGHTS FLASHING DUE TO NO POS ENTERED WITHIN 10 MINS. I TURNED IRS'S OFF THEN BACK TO ALIGN (LIGHTS STEADY) THEN ERRONEOUSLY ENTERED PBI COORDINATES INSTEAD OF FLL. OUR TRAINING STATES YOU NEED TO ENTER A NEW POS 3 TIMES IF SIGNIFICANTLY DIFFERENT FROM SHUTDOWN POS. THIS ALIGNMENT TOOK ONLY 1 INCORRECT POS ENTRY TO ENTER AND COMPLETE ALIGNMENT. THIS RESULTED IN A 37 MI POS ERROR WHICH LASTED THE ENTIRE FLT FROM FLL. AFTER TKOF WE WERE ON RADAR VECTORS AND HDG DEVS DUE TO WX TILL APCHING CHS VOR. THIS IS WHERE WE DISCOVERED THE NAV ERROR AND THEN ADVISED ATC OF OUR FMS NAV ERROR. SINCE THE HDG FROM FLL TO PBI IS APPROX THE SAME AS OUR RTE OF FLT, WE PROBABLY WERE NOT VERY FAR OFF COURSE LATERALLY.
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.