A B757 PIC's report on another map shift during the civet 4 STAR arrival for lax runway 25L approach. Reporter was aware of the potential for a map shift and had used the new procedure of manual VOR tuning which did not correct the problem. The aircraft was 1 mi right of the localizer course when the map display showed the aircraft on the centerline of the localizer course.

Home

Browse by month

Random

Latest

About

Contact

Attributes
ACN	399849
Time
Date	199804
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : lax
State Reference	CA
Altitude	msl bound lower : 10000 msl bound upper : 10000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : lax
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent : approach
Route In Use	approach : straight in arrival other arrival star : star
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 200 flight time total : 14000
ASRS Report	399849
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	aircraft equipment problem : less severe non adherence : published procedure non adherence : clearance other anomaly other other spatial deviation
Independent Detector	other controllera other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course other other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation other

Narrative:

We proceeded on lax civet arrival without usual restr due to light traffic. Due to previous map shifts at lax, a manual VOR tune procedure was implemented, which we complied with. When the first officer went to expanded localizer to back up arrival, his HSI showed full scale deflection, even though map showed on centerline. Upon verifying ILS accuracy, we began correction to localizer course. Shortly thereafter approach control advised we were 1 mi right of course. We advised runway in sight and flew visual approach. With localizer centered map was still .8 mi in error. We advised company to question their new 'fix' to map shift problems and recommended flts to fly a 'non map' manual approach navigation on the civet arrival.

Original NASA ASRS Text

Title: A B757 PIC'S RPT ON ANOTHER MAP SHIFT DURING THE CIVET 4 STAR ARR FOR LAX RWY 25L APCH. RPTR WAS AWARE OF THE POTENTIAL FOR A MAP SHIFT AND HAD USED THE NEW PROC OF MANUAL VOR TUNING WHICH DID NOT CORRECT THE PROB. THE ACFT WAS 1 MI R OF THE LOC COURSE WHEN THE MAP DISPLAY SHOWED THE ACFT ON THE CTRLINE OF THE LOC COURSE.

Narrative: WE PROCEEDED ON LAX CIVET ARR WITHOUT USUAL RESTR DUE TO LIGHT TFC. DUE TO PREVIOUS MAP SHIFTS AT LAX, A MANUAL VOR TUNE PROC WAS IMPLEMENTED, WHICH WE COMPLIED WITH. WHEN THE FO WENT TO EXPANDED LOC TO BACK UP ARR, HIS HSI SHOWED FULL SCALE DEFLECTION, EVEN THOUGH MAP SHOWED ON CTRLINE. UPON VERIFYING ILS ACCURACY, WE BEGAN CORRECTION TO LOC COURSE. SHORTLY THEREAFTER APCH CTL ADVISED WE WERE 1 MI R OF COURSE. WE ADVISED RWY IN SIGHT AND FLEW VISUAL APCH. WITH LOC CTRED MAP WAS STILL .8 MI IN ERROR. WE ADVISED COMPANY TO QUESTION THEIR NEW 'FIX' TO MAP SHIFT PROBS AND RECOMMENDED FLTS TO FLY A 'NON MAP' MANUAL APCH NAV ON THE CIVET ARR.

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.