Narrative:

Being vectored for right traffic lax runway 24R; on downwind leg; we were in and out of a cloud layer that was ragged from approximately 4;000 ft to 7;000 ft. While still on downwind; the controller pointed out traffic that would precede us; but the traffic would be landing 24L and we would land 24R. We stated that we were IMC and could not make visual contact. I was vigilant of TCAS targets; but there was no obvious target that we were following. We were vectored to a base leg and given a descent. At that point; the controller again pointed out B767 traffic and that the traffic was for 24L and we would land 24R. We had the airport clearly in sight and I had an aircraft in sight that seemed to match the position we were given for our traffic. Checking both visually and on TCAS; I saw no other aircraft in the same general area that we could possibly be following. The traffic was significantly closer to the airport than we were and was on final. We were still on base and I saw no other traffic. I told the first officer 'airport in sight; traffic in sight'. He made the same call to ATC and we were given a final heading to intercept the runway 24R localizer and were cleared for the visual approach. We captured the localizer with no overshoot; captured the glide slope and started a normal; even somewhat early; configuration and speed reduction sequence. At somewhere slightly below 2;000 ft; TCAS gave a 'monitor vertical speed' RA. I disconnected the autopilot and swallowed the descent. At that point; I saw the B767; which was on final for runway 24L; ahead of and lower than us; flying a parallel course. At about the same time; lax tower instructed us to not pass the B767. I slowed to final approach speed; heard 'clear of conflict' and regained the runway 24R glide slope. Separation was very adequate by this point; with the B767 significantly out in front of us and for the parallel runway. We were able to resolve the conflict with minimal maneuvering. I do not believe that this was the aircraft that I originally called in sight and I did not see this aircraft on our TCAS prior to receiving the RA.

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Original NASA ASRS Text

Title: Air Carrier inbound to LAX for a Visual Approach to Runway 24R sighted the wrong aircraft with respect to sequence. Separation was not compromised.

Narrative: Being vectored for right traffic LAX Runway 24R; on downwind leg; we were in and out of a cloud layer that was ragged from approximately 4;000 FT to 7;000 FT. While still on downwind; the Controller pointed out traffic that would precede us; but the traffic would be landing 24L and we would land 24R. We stated that we were IMC and could not make visual contact. I was vigilant of TCAS targets; but there was no obvious target that we were following. We were vectored to a base leg and given a descent. At that point; the Controller again pointed out B767 traffic and that the traffic was for 24L and we would land 24R. We had the airport clearly in sight and I had an aircraft in sight that seemed to match the position we were given for our traffic. Checking both visually and on TCAS; I saw no other aircraft in the same general area that we could possibly be following. The traffic was significantly closer to the airport than we were and was on final. We were still on base and I saw no other traffic. I told the First Officer 'airport in sight; traffic in sight'. He made the same call to ATC and we were given a final heading to intercept the Runway 24R localizer and were cleared for the visual approach. We captured the localizer with no overshoot; captured the glide slope and started a normal; even somewhat early; configuration and speed reduction sequence. At somewhere slightly below 2;000 FT; TCAS gave a 'MONITOR VERTICAL SPEED' RA. I disconnected the autopilot and swallowed the descent. At that point; I saw the B767; which was on final for Runway 24L; ahead of and lower than us; flying a parallel course. At about the same time; LAX Tower instructed us to not pass the B767. I slowed to final approach speed; heard 'CLEAR OF CONFLICT' and regained the Runway 24R glide slope. Separation was very adequate by this point; with the B767 significantly out in front of us and for the parallel runway. We were able to resolve the conflict with minimal maneuvering. I do not believe that this was the aircraft that I originally called in sight and I did not see this aircraft on our TCAS prior to receiving the RA.

Data retrieved from NASA's ASRS site as of July 2013 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.