A320 flight crew during visual approach to runway 25L las followed wrong aircraft to runway.

Attributes
ACN	694400
Time
Date	200604
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : las.airport
State Reference	NV
Altitude	msl single value : 6000
Environment
Flight Conditions	VMC
Aircraft 1
Controlling Facilities	tracon : l30.tracon
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Route In Use	approach : traffic pattern
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : l30.tracon
Operator	Other
Make Model Name	Dassault-Breguet Undifferentiated or Other Model
Operating Under FAR Part	Part 91
Flight Phase	descent : approach
Route In Use	approach : traffic pattern
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Experience	flight time last 90 days : 250 flight time total : 12000 flight time type : 400
ASRS Report	694400
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	conflict : airborne less severe non adherence : clearance other spatial deviation
Independent Detector	other controllera
Resolutory Action	controller : issued advisory controller : issued new clearance
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

I was the PNF in trail behind 2 other aircraft on the downwind for runway 25L; las. As we leveled off at 6000 ft; vegas approach asked us if we had the 'falcon jet' in sight. I saw an aircraft at our 11 O'clock position at about 5 mi. I asked the first officer (PF) if he had the traffic. I told him I saw it there at 11 O'clock position low. He then spotted the same aircraft and told me. I told ATC that we had the 'falcon jet at 11 O'clock position and the runway in sight....' ATC then said; 'cleared the visual approach to runway 25L behind the falcon jet....' both the first officer and I saw no other aircraft in front of us; nor were we informed that we were 1 of 3 aircraft in trail. As the aircraft that we saw started its dogleg turn; we began our base turn; and I then set 3800 ft for the relin OM; as per SOP. Shortly thereafter; we began our descent while watching the aircraft in front of us. Just as we descended through 5300 ft; ATC told us that we were following 'the wrong aircraft.' they told us to maintain 6000 ft; and turn left to a heading of 350 degrees; which we immediately complied. We both (first officer and I) then saw the real 'falcon jet' at our 2 O'clock position and about 2 mi; also in a left turn to base. The outcome was that we both mistook the aircraft in front of the falcon jet as our traffic to follow. ATC assumed we had the aircraft between us in sight. Apparently we were #3; the falcon jet was #2; and the rj was #1. We did not see #2; and thought #1 was our traffic to follow. When we told ATC we had the falcon jet in sight; we both thought we did; as none of us saw any other aircraft. I spoke to ATC upon landing and they told me that they do not like issuing visual approach clearance on downwind for the very reason that we experienced -- especially if there are a series of aircraft in trail. From a human factors standpoint; clearly there was a misident of the aircraft we were to follow on the visual. ATC did not catch it until we began our turn and they saw that we were turning inside our traffic. ATC could have told us that we were #3 in trail behind an rj and a falcon jet; follow the falcon jet; cleared the visual runway 25L. Had they said that; we would have then known that something was wrong; because we only saw 1 airplane in front of us.

Original NASA ASRS Text

Title: A320 FLT CREW DURING VISUAL APCH TO RWY 25L LAS FOLLOWED WRONG ACFT TO RWY.

Narrative: I WAS THE PNF IN TRAIL BEHIND 2 OTHER ACFT ON THE DOWNWIND FOR RWY 25L; LAS. AS WE LEVELED OFF AT 6000 FT; VEGAS APCH ASKED US IF WE HAD THE 'FALCON JET' IN SIGHT. I SAW AN ACFT AT OUR 11 O'CLOCK POS AT ABOUT 5 MI. I ASKED THE FO (PF) IF HE HAD THE TFC. I TOLD HIM I SAW IT THERE AT 11 O'CLOCK POS LOW. HE THEN SPOTTED THE SAME ACFT AND TOLD ME. I TOLD ATC THAT WE HAD THE 'FALCON JET AT 11 O'CLOCK POS AND THE RWY IN SIGHT....' ATC THEN SAID; 'CLRED THE VISUAL APCH TO RWY 25L BEHIND THE FALCON JET....' BOTH THE FO AND I SAW NO OTHER ACFT IN FRONT OF US; NOR WERE WE INFORMED THAT WE WERE 1 OF 3 ACFT IN TRAIL. AS THE ACFT THAT WE SAW STARTED ITS DOGLEG TURN; WE BEGAN OUR BASE TURN; AND I THEN SET 3800 FT FOR THE RELIN OM; AS PER SOP. SHORTLY THEREAFTER; WE BEGAN OUR DSCNT WHILE WATCHING THE ACFT IN FRONT OF US. JUST AS WE DSNDED THROUGH 5300 FT; ATC TOLD US THAT WE WERE FOLLOWING 'THE WRONG ACFT.' THEY TOLD US TO MAINTAIN 6000 FT; AND TURN L TO A HDG OF 350 DEGS; WHICH WE IMMEDIATELY COMPLIED. WE BOTH (FO AND I) THEN SAW THE REAL 'FALCON JET' AT OUR 2 O'CLOCK POS AND ABOUT 2 MI; ALSO IN A L TURN TO BASE. THE OUTCOME WAS THAT WE BOTH MISTOOK THE ACFT IN FRONT OF THE FALCON JET AS OUR TFC TO FOLLOW. ATC ASSUMED WE HAD THE ACFT BTWN US IN SIGHT. APPARENTLY WE WERE #3; THE FALCON JET WAS #2; AND THE RJ WAS #1. WE DID NOT SEE #2; AND THOUGHT #1 WAS OUR TFC TO FOLLOW. WHEN WE TOLD ATC WE HAD THE FALCON JET IN SIGHT; WE BOTH THOUGHT WE DID; AS NONE OF US SAW ANY OTHER ACFT. I SPOKE TO ATC UPON LNDG AND THEY TOLD ME THAT THEY DO NOT LIKE ISSUING VISUAL APCH CLRNC ON DOWNWIND FOR THE VERY REASON THAT WE EXPERIENCED -- ESPECIALLY IF THERE ARE A SERIES OF ACFT IN TRAIL. FROM A HUMAN FACTORS STANDPOINT; CLRLY THERE WAS A MISIDENT OF THE ACFT WE WERE TO FOLLOW ON THE VISUAL. ATC DID NOT CATCH IT UNTIL WE BEGAN OUR TURN AND THEY SAW THAT WE WERE TURNING INSIDE OUR TFC. ATC COULD HAVE TOLD US THAT WE WERE #3 IN TRAIL BEHIND AN RJ AND A FALCON JET; FOLLOW THE FALCON JET; CLRED THE VISUAL RWY 25L. HAD THEY SAID THAT; WE WOULD HAVE THEN KNOWN THAT SOMETHING WAS WRONG; BECAUSE WE ONLY SAW 1 AIRPLANE IN FRONT OF US.

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.