Narrative:

On downwind for 24R, we were cleared for a visibility approach to follow an large transport on final. Simultaneous approachs to parallel runways were being conducted. Passing abeam the large transport I rolled into a right turn to start the base leg. I was then momentarily distracted by the controller advising the position of an medium large transport at our 7-8 O'clock, which had us visually and was to maintain visibility sep with us while completing his approach to 24L. Spotting this traffic, I returned my scan to where I thought the large transport should then be, and sighted what I thought to be the large transport. (It later turned out to be a widebody transport.) as I followed the aircraft ahead, I scanned the localizer for 24R and noted it was deflected full right. An immediate correction was initiated back to course and landing was completed uneventfully. The medium large transport on approach to 24L was far enough behind us so as not to create an immediate conflict, but he must have been surprised by us flying through his 'line to the airport.' the apparent cause of this incident was failure to visually maintain contact at all times and failure to quickly scan all instruments, allowing us to fly through the localizer. In the future, when cleared for a visibility, I will make sure I back up the approach 100% of the time with all navaids. Also contributory was the copilot being preoccupied running his before landing checklist instead of monitoring the approach in a critical phase of flight.

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Original NASA ASRS Text

Title: ACR MLG OVERSHOOTS TURN ON VISUAL APCH TO A PARALLEL RWY WHILE DISTRACTED WITH TRAFFIC WATCH AND TASK.

Narrative: ON DOWNWIND FOR 24R, WE WERE CLRED FOR A VIS APCH TO FOLLOW AN LGT ON FINAL. SIMULTANEOUS APCHS TO PARALLEL RWYS WERE BEING CONDUCTED. PASSING ABEAM THE LGT I ROLLED INTO A RIGHT TURN TO START THE BASE LEG. I WAS THEN MOMENTARILY DISTRACTED BY THE CTLR ADVISING THE POS OF AN MLG AT OUR 7-8 O'CLOCK, WHICH HAD US VISUALLY AND WAS TO MAINTAIN VIS SEP WITH US WHILE COMPLETING HIS APCH TO 24L. SPOTTING THIS TFC, I RETURNED MY SCAN TO WHERE I THOUGHT THE LGT SHOULD THEN BE, AND SIGHTED WHAT I THOUGHT TO BE THE LGT. (IT LATER TURNED OUT TO BE A WDB.) AS I FOLLOWED THE ACFT AHEAD, I SCANNED THE LOC FOR 24R AND NOTED IT WAS DEFLECTED FULL RIGHT. AN IMMEDIATE CORRECTION WAS INITIATED BACK TO COURSE AND LNDG WAS COMPLETED UNEVENTFULLY. THE MLG ON APCH TO 24L WAS FAR ENOUGH BEHIND US SO AS NOT TO CREATE AN IMMEDIATE CONFLICT, BUT HE MUST HAVE BEEN SURPRISED BY US FLYING THROUGH HIS 'LINE TO THE ARPT.' THE APPARENT CAUSE OF THIS INCIDENT WAS FAILURE TO VISUALLY MAINTAIN CONTACT AT ALL TIMES AND FAILURE TO QUICKLY SCAN ALL INSTRUMENTS, ALLOWING US TO FLY THROUGH THE LOC. IN THE FUTURE, WHEN CLRED FOR A VIS, I WILL MAKE SURE I BACK UP THE APCH 100% OF THE TIME WITH ALL NAVAIDS. ALSO CONTRIBUTORY WAS THE COPLT BEING PREOCCUPIED RUNNING HIS BEFORE LNDG CHKLIST INSTEAD OF MONITORING THE APCH IN A CRITICAL PHASE OF FLT.

Data retrieved from NASA's ASRS site as of August 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.