Narrative:

During the civet arrival to lax controller stated we were right of track. Both VOR course needles were centered on the inbound radial (249 off lax). At arnes I started an autoplt descent but the autoplt began down way too steep and fast so I disconnected it. We leveled at 9000 ft and the first officer noticed we were right of course. I corrected back left. After a few seconds I corrected left more and ATC called and said that we were right of course. We re-intercepted the inbound localizer with no further problems. I am not sure where the problem began. It is possible that the VOR lock on was not accurate since approach had informed us that we were right of course and we showed right on the radial. Also it is possible that during the autoplt pitch-down I wandered off course, but since that period of time was so short I don't think I could have gone that far off course. I believe that when I switched from lax to the ILS localizer at arnes is when the needle or localizer displacement occurred but since I was busy with the aircraft I failed to recognize the error. The first officer did an excellent job of noticing the lateral displacement and bringing it to my attention. Callback conversation with reporter revealed the following information: reporter rarely flies into lax. He tracked into lax using the VOR only up to the 33 DME point. Then he switched to ilax. He feels now he waited too long to switch to ILS for course guidance. Civet is defined by the arrival chart as 52 DME on the runway 25L ILS, therefore he feels he would tune into the runway 25L ILS at least by civet the next time he flies into lax. Reporter was just uncertain about what techniques and procedures to use when flying into lax. Supplemental information from acn 364246: at that time I noticed full scale CDI deflection to the left and pointed this out to the captain. He made a small correction. 1 min later, southern cal approach said we were right of course. We acknowledged and made a larger correction. About 2 mins later socal approach asked if we were still correcting because we were still right of course. By this time we had a 30 degree heading correction back to the CDI with still full scale CDI deviation. Seconds later the CDI came off the wall and centered. No further problems.

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Original NASA ASRS Text

Title: MD80 ACFT FLIES OFF COURSE WHILE DSNDING INTO LAX.

Narrative: DURING THE CIVET ARR TO LAX CTLR STATED WE WERE R OF TRACK. BOTH VOR COURSE NEEDLES WERE CTRED ON THE INBOUND RADIAL (249 OFF LAX). AT ARNES I STARTED AN AUTOPLT DSCNT BUT THE AUTOPLT BEGAN DOWN WAY TOO STEEP AND FAST SO I DISCONNECTED IT. WE LEVELED AT 9000 FT AND THE FO NOTICED WE WERE R OF COURSE. I CORRECTED BACK L. AFTER A FEW SECONDS I CORRECTED L MORE AND ATC CALLED AND SAID THAT WE WERE R OF COURSE. WE RE-INTERCEPTED THE INBOUND LOC WITH NO FURTHER PROBS. I AM NOT SURE WHERE THE PROB BEGAN. IT IS POSSIBLE THAT THE VOR LOCK ON WAS NOT ACCURATE SINCE APCH HAD INFORMED US THAT WE WERE R OF COURSE AND WE SHOWED R ON THE RADIAL. ALSO IT IS POSSIBLE THAT DURING THE AUTOPLT PITCH-DOWN I WANDERED OFF COURSE, BUT SINCE THAT PERIOD OF TIME WAS SO SHORT I DON'T THINK I COULD HAVE GONE THAT FAR OFF COURSE. I BELIEVE THAT WHEN I SWITCHED FROM LAX TO THE ILS LOC AT ARNES IS WHEN THE NEEDLE OR LOC DISPLACEMENT OCCURRED BUT SINCE I WAS BUSY WITH THE ACFT I FAILED TO RECOGNIZE THE ERROR. THE FO DID AN EXCELLENT JOB OF NOTICING THE LATERAL DISPLACEMENT AND BRINGING IT TO MY ATTN. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR RARELY FLIES INTO LAX. HE TRACKED INTO LAX USING THE VOR ONLY UP TO THE 33 DME POINT. THEN HE SWITCHED TO ILAX. HE FEELS NOW HE WAITED TOO LONG TO SWITCH TO ILS FOR COURSE GUIDANCE. CIVET IS DEFINED BY THE ARR CHART AS 52 DME ON THE RWY 25L ILS, THEREFORE HE FEELS HE WOULD TUNE INTO THE RWY 25L ILS AT LEAST BY CIVET THE NEXT TIME HE FLIES INTO LAX. RPTR WAS JUST UNCERTAIN ABOUT WHAT TECHNIQUES AND PROCS TO USE WHEN FLYING INTO LAX. SUPPLEMENTAL INFO FROM ACN 364246: AT THAT TIME I NOTICED FULL SCALE CDI DEFLECTION TO THE L AND POINTED THIS OUT TO THE CAPT. HE MADE A SMALL CORRECTION. 1 MIN LATER, SOUTHERN CAL APCH SAID WE WERE R OF COURSE. WE ACKNOWLEDGED AND MADE A LARGER CORRECTION. ABOUT 2 MINS LATER SOCAL APCH ASKED IF WE WERE STILL CORRECTING BECAUSE WE WERE STILL R OF COURSE. BY THIS TIME WE HAD A 30 DEG HDG CORRECTION BACK TO THE CDI WITH STILL FULL SCALE CDI DEV. SECONDS LATER THE CDI CAME OFF THE WALL AND CTRED. NO FURTHER PROBS.

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.