Narrative:

The problem arose because pam RAPCON neglected to apply merging target procedures as required in FAA handbook 7110.65G, paragraph 5-8(a)(2), and neglected to ensure the conflict between air carrier X and small transport Y was resolved prior to communication transfer. Air carrier X reported on pfn tower frequency in the vicinity of the OM on runway 14 ILS approach. I observed traffic at air carrier X 1 O'clock position, 2 mi, converging at 2000 ft. Air carrier X altitude was 2500 ft, descending. I issued traffic which I believed to be a flight check operating in VFR conditions east to west across the final at 2000 ft. Air carrier X reported traffic in sight crossing his approach path and also reported a TCASII alert. Air carrier X initially appeared to be surprised when traffic was issued. He was not aware of the traffic until I issued the traffic information. Another discrete code was observed behind air carrier X at 2300 ft. When we inquired about that target, we were advised that the target was flight check. We then asked about the XXXX discrete code and target that passed in front of air carrier X. We were told that the XXXX code was small transport Y. Small transport Y was never pointed out to the tower nor to air carrier X by pam RAPCON. Corrective actions: pam RAPCON should be required to carry data blocks with the aircraft call sign at all times. Some controllers use partial data blocks which only show the discrete codes and altitudes. Because of this practice, when I saw the XXXX code I believed it to be the flight check aircraft which had been previously coordinated with tower.

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Original NASA ASRS Text

Title: ACR X TCASII RA WITH VFR SMT Y NMAC EVASIVE ACTION TAKEN. SEE AND AVOID CONCEPT.

Narrative: THE PROB AROSE BECAUSE PAM RAPCON NEGLECTED TO APPLY MERGING TARGET PROCS AS REQUIRED IN FAA HANDBOOK 7110.65G, PARAGRAPH 5-8(A)(2), AND NEGLECTED TO ENSURE THE CONFLICT BTWN ACR X AND SMT Y WAS RESOLVED PRIOR TO COM TRANSFER. ACR X RPTED ON PFN TWR FREQ IN THE VICINITY OF THE OM ON RWY 14 ILS APCH. I OBSERVED TFC AT ACR X 1 O'CLOCK POS, 2 MI, CONVERGING AT 2000 FT. ACR X ALT WAS 2500 FT, DSNDING. I ISSUED TFC WHICH I BELIEVED TO BE A FLT CHK OPERATING IN VFR CONDITIONS E TO W ACROSS THE FINAL AT 2000 FT. ACR X RPTED TFC IN SIGHT XING HIS APCH PATH AND ALSO RPTED A TCASII ALERT. ACR X INITIALLY APPEARED TO BE SURPRISED WHEN TFC WAS ISSUED. HE WAS NOT AWARE OF THE TFC UNTIL I ISSUED THE TFC INFO. ANOTHER DISCRETE CODE WAS OBSERVED BEHIND ACR X AT 2300 FT. WHEN WE INQUIRED ABOUT THAT TARGET, WE WERE ADVISED THAT THE TARGET WAS FLT CHK. WE THEN ASKED ABOUT THE XXXX DISCRETE CODE AND TARGET THAT PASSED IN FRONT OF ACR X. WE WERE TOLD THAT THE XXXX CODE WAS SMT Y. SMT Y WAS NEVER POINTED OUT TO THE TWR NOR TO ACR X BY PAM RAPCON. CORRECTIVE ACTIONS: PAM RAPCON SHOULD BE REQUIRED TO CARRY DATA BLOCKS WITH THE ACFT CALL SIGN AT ALL TIMES. SOME CTLRS USE PARTIAL DATA BLOCKS WHICH ONLY SHOW THE DISCRETE CODES AND ALTS. BECAUSE OF THIS PRACTICE, WHEN I SAW THE XXXX CODE I BELIEVED IT TO BE THE FLT CHK ACFT WHICH HAD BEEN PREVIOUSLY COORDINATED WITH TWR.

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.