Narrative:

Flight air carrier X on feb/xa/00 was diverting to lax due to airport closure in san. Flight was on vector from smo VOR on redeye 2 arrival. Controller pointed out 11 O'clock traffic and we responded that we had traffic in sight. Controller told us to follow traffic and cleared visual approach to runway 6R. While on base leg, descending to 3500 ft, controller advised that we were cutting off the traffic we were to follow and to make an immediate turn to 250 degrees and descend to 2500 ft. We then saw the traffic, a second aircraft, on TCASII. I believe we were as close as 1-2 mi, 400 ft from the traffic. Factors involved: this was the second diversion for this flight. The first having been a medical emergency into den. The hour was late, about XA30 at the crew's base. Possibly we failed to check all quadrants for traffic. Possibly the traffic we saw was not that which was pointed out. In any case, we probably did not expect 2 other aircraft besides us to be on a visual. The fact that it was dark, over water and to an approach not often flown had me at least focused on the instruments and the instrument procedure and not on visual scanning.

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Original NASA ASRS Text

Title: A320 CREW DIVERTING TO LAX FROM SAN ACCEPTS VISUAL APCH CLRNC TO FOLLOW TFC TO ARPT BUT LATER FINDS OUT FOLLOWING WRONG ACFT.

Narrative: FLT ACR X ON FEB/XA/00 WAS DIVERTING TO LAX DUE TO ARPT CLOSURE IN SAN. FLT WAS ON VECTOR FROM SMO VOR ON REDEYE 2 ARR. CTLR POINTED OUT 11 O'CLOCK TFC AND WE RESPONDED THAT WE HAD TFC IN SIGHT. CTLR TOLD US TO FOLLOW TFC AND CLRED VISUAL APCH TO RWY 6R. WHILE ON BASE LEG, DSNDING TO 3500 FT, CTLR ADVISED THAT WE WERE CUTTING OFF THE TFC WE WERE TO FOLLOW AND TO MAKE AN IMMEDIATE TURN TO 250 DEGS AND DSND TO 2500 FT. WE THEN SAW THE TFC, A SECOND ACFT, ON TCASII. I BELIEVE WE WERE AS CLOSE AS 1-2 MI, 400 FT FROM THE TFC. FACTORS INVOLVED: THIS WAS THE SECOND DIVERSION FOR THIS FLT. THE FIRST HAVING BEEN A MEDICAL EMER INTO DEN. THE HR WAS LATE, ABOUT XA30 AT THE CREW'S BASE. POSSIBLY WE FAILED TO CHK ALL QUADRANTS FOR TFC. POSSIBLY THE TFC WE SAW WAS NOT THAT WHICH WAS POINTED OUT. IN ANY CASE, WE PROBABLY DID NOT EXPECT 2 OTHER ACFT BESIDES US TO BE ON A VISUAL. THE FACT THAT IT WAS DARK, OVER WATER AND TO AN APCH NOT OFTEN FLOWN HAD ME AT LEAST FOCUSED ON THE INSTS AND THE INST PROC AND NOT ON VISUAL SCANNING.

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.