Narrative:

Crossed padus intersection 21 DME 4000 ft per ATC. Was advised #2 for approach. Small transport Y 8 mi DME cleared to 1500 ft. Approach requested we report 12 DME, complied at 2000 ft. We were then to report shoreline which is about 10 DME, we broke out of clouds at about 2000 ft. We were not advised of any traffic. TCASII was showing no traffic. At shoreline we reported shoreline approach turned us over to tower (never cleared us for approach). At shoreline 1500 ft, we called tower. Immediately TCASII reported conflict (yellow). This was the first time other aircraft showed on TCASII. He was shown at 1500 ft (same altitude). TCASII said climb, climb. We complied. Called missed approach to tower at about 1 O'clock and 500 ft estimated was small transport Y in a right turn. We then executed missed approach then returned to airport and landed.

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Original NASA ASRS Text

Title: NMAC BTWN 2 COMMUTER ACFT AT FPO. TCASII ALERTED CREW OF LTT X TO PRESENCE OF SMT Y.

Narrative: CROSSED PADUS INTXN 21 DME 4000 FT PER ATC. WAS ADVISED #2 FOR APCH. SMT Y 8 MI DME CLRED TO 1500 FT. APCH REQUESTED WE RPT 12 DME, COMPLIED AT 2000 FT. WE WERE THEN TO RPT SHORELINE WHICH IS ABOUT 10 DME, WE BROKE OUT OF CLOUDS AT ABOUT 2000 FT. WE WERE NOT ADVISED OF ANY TFC. TCASII WAS SHOWING NO TFC. AT SHORELINE WE RPTED SHORELINE APCH TURNED US OVER TO TWR (NEVER CLRED US FOR APCH). AT SHORELINE 1500 FT, WE CALLED TWR. IMMEDIATELY TCASII RPTED CONFLICT (YELLOW). THIS WAS THE FIRST TIME OTHER ACFT SHOWED ON TCASII. HE WAS SHOWN AT 1500 FT (SAME ALT). TCASII SAID CLB, CLB. WE COMPLIED. CALLED MISSED APCH TO TWR AT ABOUT 1 O'CLOCK AND 500 FT ESTIMATED WAS SMT Y IN A R TURN. WE THEN EXECUTED MISSED APCH THEN RETURNED TO ARPT AND LANDED.

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.