Narrative:

On a night approach to 12R stl, on a 15 mi final approach points out traffic for us to follow. The sky is very crowded and ATC states traffic to follow is at 12 O'clock. I see someone on a left base turn to final and say so to which ATC clears us to follow traffic, cleared for visual. Sometime shortly afterwards approach tells us speed at our discretion and we naturally sped up. We changed to tower frequency and I heard tower tell a departing aircraft position and hold with traffic on a 2 3/4 mi final. That's the aircraft I was following and was more than 3 mi in trail even with a 50-80 KT closure rate. About that time I saw an medium large transport on final at our altitude and maybe 2000 ft or less ahead. I started an evasive maneuver to the right and tower called me simultaneously wondering what I was doing. I stated the traffic I saw and was following was apparently not the traffic approach had pointed out.

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Original NASA ASRS Text

Title: COMMUTER LTT CLOSE PROX WITH ACR MLG THE COMMUTER HAD BEEN TOLD TO FOLLOW. FLC WAS LOOKING AT THE WRONG ACFT ON STRAIGHT IN TO RWY 12R AT STL.

Narrative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

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.