Narrative:

When we were on a right downwind for an ILS runway 27, ATC asked us if we saw a king air maneuvering for final for the same runway. He said the traffic was at 1 O'clock position. My first officer and I both saw an aircraft that we thought was at 1 O'clock low position and we called the traffic in sight. We were cleared the visual for runway 27 behind the traffic. On right base about 2.5 mi to the inbound course, the controller asked us again if we had the aircraft to follow. He said it appeared that we were cutting inside of him. We immediately looked ahead and to the left and saw the aircraft that he was talking about right in front of us, established on final. I took the aircraft off autoplt and banked left to increase separation, and then maneuvered around behind the traffic. The aircraft we had thought he was talking about was already 3 mi or so up ahead of the 'king air' traffic (the king air turned out to be a beech 1900). The rest of the approach was uneventful. I guess the best way to respond to an ATC traffic query when he wants you to follow someone is to say something like 'I see traffic at my xx O'clock position and about xx mi' and make your very best position estimate backing it up with TCASII information if available. Hopefully then if that's not the right aircraft, ATC will catch it. We looked at the traffic that we saw, looked at the TCASII and simply said 'roger, we have the traffic' thereby denying ATC corroborating evidence.

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Original NASA ASRS Text

Title: FLC OF AN MLG FOLLOWED THE WRONG TFC WHEN CLRED FOR A VISUAL APCH DUE TO SIGHTING WHAT THEY THOUGHT WAS THEIR TFC. APCH CTLR INTERVENED AND PROVIDED TFC SEPARATION.

Narrative: WHEN WE WERE ON A R DOWNWIND FOR AN ILS RWY 27, ATC ASKED US IF WE SAW A KING AIR MANEUVERING FOR FINAL FOR THE SAME RWY. HE SAID THE TFC WAS AT 1 O'CLOCK POS. MY FO AND I BOTH SAW AN ACFT THAT WE THOUGHT WAS AT 1 O'CLOCK LOW POS AND WE CALLED THE TFC IN SIGHT. WE WERE CLRED THE VISUAL FOR RWY 27 BEHIND THE TFC. ON R BASE ABOUT 2.5 MI TO THE INBOUND COURSE, THE CTLR ASKED US AGAIN IF WE HAD THE ACFT TO FOLLOW. HE SAID IT APPEARED THAT WE WERE CUTTING INSIDE OF HIM. WE IMMEDIATELY LOOKED AHEAD AND TO THE L AND SAW THE ACFT THAT HE WAS TALKING ABOUT RIGHT IN FRONT OF US, ESTABLISHED ON FINAL. I TOOK THE ACFT OFF AUTOPLT AND BANKED L TO INCREASE SEPARATION, AND THEN MANEUVERED AROUND BEHIND THE TFC. THE ACFT WE HAD THOUGHT HE WAS TALKING ABOUT WAS ALREADY 3 MI OR SO UP AHEAD OF THE 'KING AIR' TFC (THE KING AIR TURNED OUT TO BE A BEECH 1900). THE REST OF THE APCH WAS UNEVENTFUL. I GUESS THE BEST WAY TO RESPOND TO AN ATC TFC QUERY WHEN HE WANTS YOU TO FOLLOW SOMEONE IS TO SAY SOMETHING LIKE 'I SEE TFC AT MY XX O'CLOCK POS AND ABOUT XX MI' AND MAKE YOUR VERY BEST POS ESTIMATE BACKING IT UP WITH TCASII INFO IF AVAILABLE. HOPEFULLY THEN IF THAT'S NOT THE RIGHT ACFT, ATC WILL CATCH IT. WE LOOKED AT THE TFC THAT WE SAW, LOOKED AT THE TCASII AND SIMPLY SAID 'ROGER, WE HAVE THE TFC' THEREBY DENYING ATC CORROBORATING EVIDENCE.

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.