Narrative:

Air carrier X on a vector from approach control, saw a mooney with a blue tail at 10-11 O'clock at approximately the same altitude, flying on a converging course. The aircraft performed what appeared to a 'wing-over' maneuver which caused him to lose altitude fast enough to pass under us. I believe the aircraft passed within several 100 yards horizontally and a few 100 ft vertically. Had he not taken evasive action, I believe I could have avoided him by making a rapid evasive maneuver. The aircraft apparently belonged to a flight school which is located at dab. The controller appeared to be saturated. I had heard xmissions between a pilot (it seemed probable that english was not his first language) and the approach controller which indicated that the pilot had been directed to stay out of the class C airspace. It also appeared that the pilot had idented himself as 'mooney n--' and later using a flight school call sign. The same voice indicated he had my aircraft (by company name) in sight after he passed under us. There is no doubt in my mind that had we had TCASII (even tcasi) we would have seen this aircraft sooner. We had completed a turn to a northerly heading just prior to encountering the aircraft.

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Original NASA ASRS Text

Title: SMA UNAUTH PENETRATION OF CLASS C AIRSPACE HAD CONFLICT WITH ACR X EVASIVE ACTION TAKEN.

Narrative: ACR X ON A VECTOR FROM APCH CTL, SAW A MOONEY WITH A BLUE TAIL AT 10-11 O'CLOCK AT APPROX THE SAME ALT, FLYING ON A CONVERGING COURSE. THE ACFT PERFORMED WHAT APPEARED TO A 'WING-OVER' MANEUVER WHICH CAUSED HIM TO LOSE ALT FAST ENOUGH TO PASS UNDER US. I BELIEVE THE ACFT PASSED WITHIN SEVERAL 100 YARDS HORIZLY AND A FEW 100 FT VERTLY. HAD HE NOT TAKEN EVASIVE ACTION, I BELIEVE I COULD HAVE AVOIDED HIM BY MAKING A RAPID EVASIVE MANEUVER. THE ACFT APPARENTLY BELONGED TO A FLT SCHOOL WHICH IS LOCATED AT DAB. THE CTLR APPEARED TO BE SATURATED. I HAD HEARD XMISSIONS BTWN A PLT (IT SEEMED PROBABLE THAT ENGLISH WAS NOT HIS FIRST LANGUAGE) AND THE APCH CTLR WHICH INDICATED THAT THE PLT HAD BEEN DIRECTED TO STAY OUT OF THE CLASS C AIRSPACE. IT ALSO APPEARED THAT THE PLT HAD IDENTED HIMSELF AS 'MOONEY N--' AND LATER USING A FLT SCHOOL CALL SIGN. THE SAME VOICE INDICATED HE HAD MY ACFT (BY COMPANY NAME) IN SIGHT AFTER HE PASSED UNDER US. THERE IS NO DOUBT IN MY MIND THAT HAD WE HAD TCASII (EVEN TCASI) WE WOULD HAVE SEEN THIS ACFT SOONER. WE HAD COMPLETED A TURN TO A NORTHERLY HDG JUST PRIOR TO ENCOUNTERING THE 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.