Narrative:

I was being vectored for the 24R approach into lax from the north. We were level 2500' (500' below the overcast). We were close to intercepting the localizer when at my 10-11 O'clock position I saw an large transport descend below the overcast. The controller was busy and had just noticed that this large transport had busted his 3500' assigned altitude and was not level at 3000'. The large transport jet was established on the 25L localizer. While I watched the large transport jet and listened to the controller tell the jet to just stay at 3000', I flew through the 24R localizer. The controller noticed this at the same time I did, which I was almost full scale south of course. I quickly turned right to intercept. After getting on the ground my first officer told me she had said that the localizer was alive, but she had forgotten to turn her hot microphone on after a transmission to ATC. I made the mistake of concentrating too much on a possible traffic conflict and not enough on my instruments. My first officer made the mistake of not making sure her microphone was hot and that I was aware that the localizer was alive.

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Original NASA ASRS Text

Title: FLT CREW OF SMT BEING VECTORED TO 24 AT LAX BECAME FASCINATED WATCHING A JET COME OUT OF THE OVERCAST AND DESCENDED BELOW THEIR ASSIGNED ALT TO THE EXTENT THAT THEY (SMT ACFT) OVERSHOT THEIR ALIGNMENT WITH THE 24 LOCALIZER.

Narrative: I WAS BEING VECTORED FOR THE 24R APCH INTO LAX FROM THE N. WE WERE LEVEL 2500' (500' BELOW THE OVCST). WE WERE CLOSE TO INTERCEPTING THE LOC WHEN AT MY 10-11 O'CLOCK POS I SAW AN LGT DSND BELOW THE OVCST. THE CTLR WAS BUSY AND HAD JUST NOTICED THAT THIS LGT HAD BUSTED HIS 3500' ASSIGNED ALT AND WAS NOT LEVEL AT 3000'. THE LGT JET WAS ESTABLISHED ON THE 25L LOC. WHILE I WATCHED THE LGT JET AND LISTENED TO THE CTLR TELL THE JET TO JUST STAY AT 3000', I FLEW THROUGH THE 24R LOC. THE CTLR NOTICED THIS AT THE SAME TIME I DID, WHICH I WAS ALMOST FULL SCALE S OF COURSE. I QUICKLY TURNED RIGHT TO INTERCEPT. AFTER GETTING ON THE GND MY F/O TOLD ME SHE HAD SAID THAT THE LOC WAS ALIVE, BUT SHE HAD FORGOTTEN TO TURN HER HOT MIC ON AFTER A XMISSION TO ATC. I MADE THE MISTAKE OF CONCENTRATING TOO MUCH ON A POSSIBLE TFC CONFLICT AND NOT ENOUGH ON MY INSTRUMENTS. MY F/O MADE THE MISTAKE OF NOT MAKING SURE HER MIC WAS HOT AND THAT I WAS AWARE THAT THE LOC WAS ALIVE.

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.