Narrative:

Cleared for an approach into capital airport on ILS 22 at 2200'. Then approach gave vectors for a small aircraft to intercept the localizer at 2200'. My thought at the time was that the small aircraft was #2 for the approach, behind us. Seconds later the glide slope was alive. Approach called air carrier: air carrier turn to 270 degree, wrong company call name, but by the tone of voice, we both looked and spotted the small aircraft. The first officer started a right turn when approach called again with the proper call sign. We went around the small aircraft and landed. Called approach on the phone. He apologized for the incident and said he thought he had only cleared us to 5200' MSL. This would have put us over a 1000' above glide slope at the marker, assuming we passed the small aircraft at the marker. This would have made the approach and landing difficult.

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Original NASA ASRS Text

Title: NMAC BETWEEN SMA AND ACR NEAR THE OUTER MARKER ON APCH.

Narrative: CLRED FOR AN APCH INTO CAPITAL ARPT ON ILS 22 AT 2200'. THEN APCH GAVE VECTORS FOR A SMALL ACFT TO INTERCEPT THE LOC AT 2200'. MY THOUGHT AT THE TIME WAS THAT THE SMA WAS #2 FOR THE APCH, BEHIND US. SECONDS LATER THE GLIDE SLOPE WAS ALIVE. APCH CALLED ACR: ACR TURN TO 270 DEG, WRONG COMPANY CALL NAME, BUT BY THE TONE OF VOICE, WE BOTH LOOKED AND SPOTTED THE SMA. THE F/O STARTED A RIGHT TURN WHEN APCH CALLED AGAIN WITH THE PROPER CALL SIGN. WE WENT AROUND THE SMA AND LANDED. CALLED APCH ON THE PHONE. HE APOLOGIZED FOR THE INCIDENT AND SAID HE THOUGHT HE HAD ONLY CLRED US TO 5200' MSL. THIS WOULD HAVE PUT US OVER A 1000' ABOVE GLIDE SLOPE AT THE MARKER, ASSUMING WE PASSED THE SMA AT THE MARKER. THIS WOULD HAVE MADE THE APCH AND LNDG DIFFICULT.

Data retrieved from NASA's ASRS site as of August 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.