Narrative:

Briefed practice GPS approach to runway 12R. At 500 ft, captain stated that he saw something on the runway, identifiable at 400 ft as an aircraft crossing the active. Approximately 300 ft, aircraft made final turn to clear runway. As aircraft cleared, we realized that there was another aircraft directly behind the first. Simultaneously, we both initiated a go around at approximately 200-250 ft. Turned downwind to runway 12L for an uneventful landing.

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Original NASA ASRS Text

Title: RWY INCURSION BY 2 ACR ACFT DURING APCH TO OCCUPIED RWY WHICH IS ABANDONED BY THE FLT CREW OF AN APCHING B737 TO RWY 12R AT STL, MO.

Narrative: BRIEFED PRACTICE GPS APCH TO RWY 12R. AT 500 FT, CAPT STATED THAT HE SAW SOMETHING ON THE RWY, IDENTIFIABLE AT 400 FT AS AN ACFT XING THE ACTIVE. APPROX 300 FT, ACFT MADE FINAL TURN TO CLR RWY. AS ACFT CLRED, WE REALIZED THAT THERE WAS ANOTHER ACFT DIRECTLY BEHIND THE FIRST. SIMULTANEOUSLY, WE BOTH INITIATED A GAR AT APPROX 200-250 FT. TURNED DOWNWIND TO RWY 12L FOR AN UNEVENTFUL LNDG.

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.