Narrative:

Light aircraft at 12000 ft flying around, no transponder, while large aircraft are flying around in the area (military and civilian) not bright at all! Near miss, almost a midair out of ict. Flight XXX ict-mem on climb out of 12000 ft. No TCASII warning. ATC had no radar contact with this aircraft.

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Original NASA ASRS Text

Title: A DC9 PIC'S RPT OF AN NMAC WITH A CITABRIA AT 12000 FT. NO TARGET ON TCASII OR ATC RADAR.

Narrative: LIGHT ACFT AT 12000 FT FLYING AROUND, NO XPONDER, WHILE LARGE ACFT ARE FLYING AROUND IN THE AREA (MIL AND CIVILIAN) NOT BRIGHT AT ALL! NEAR MISS, ALMOST A MIDAIR OUT OF ICT. FLT XXX ICT-MEM ON CLBOUT OF 12000 FT. NO TCASII WARNING. ATC HAD NO RADAR CONTACT WITH THIS ACFT.

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.