Narrative:

On approach at lax ILS runway 25R between shell and fogla we received a TA from the TCAS. I visually acquired the target to our north and told the first officer to keep an eye on him. We then received an RA climb from the TCAS and complied with the command to climb. Approach asked what we were doing; then realized the mistake and cleared us for a visual approach to runway 25R. The dash 8 had overshot final and was nearly lined up with our runway. We came within 400 ft or less of the other aircraft. We then had to make a pretty aggressive descent in order to be stable at 1000 ft. Landing and taxi to gate were uneventful. Approach could have pointed out the traffic prior to us getting the TA alert and we may have been able to call attention to his flight path earlier.

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Original NASA ASRS Text

Title: B737-700 FLT CREW HAS TCAS RA DURING ILS RWY 25R LAX.

Narrative: ON APCH AT LAX ILS RWY 25R BTWN SHELL AND FOGLA WE RECEIVED A TA FROM THE TCAS. I VISUALLY ACQUIRED THE TARGET TO OUR N AND TOLD THE FO TO KEEP AN EYE ON HIM. WE THEN RECEIVED AN RA CLB FROM THE TCAS AND COMPLIED WITH THE COMMAND TO CLB. APCH ASKED WHAT WE WERE DOING; THEN REALIZED THE MISTAKE AND CLRED US FOR A VISUAL APCH TO RWY 25R. THE DASH 8 HAD OVERSHOT FINAL AND WAS NEARLY LINED UP WITH OUR RWY. WE CAME WITHIN 400 FT OR LESS OF THE OTHER ACFT. WE THEN HAD TO MAKE A PRETTY AGGRESSIVE DSCNT IN ORDER TO BE STABLE AT 1000 FT. LNDG AND TAXI TO GATE WERE UNEVENTFUL. APCH COULD HAVE POINTED OUT THE TFC PRIOR TO US GETTING THE TA ALERT AND WE MAY HAVE BEEN ABLE TO CALL ATTN TO HIS FLT PATH EARLIER.

Data retrieved from NASA's ASRS site as of January 2009 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.