Narrative:

I was the instructing cfii on an instrument (IFR flight plan) cross country flight dab-mlb-dab. On the way back to dab, we requested ILS runway 7L to dab. While our aircraft was being vectored downwind (south side of localizer) my student flew, as assigned by ATC, westerly heading. I do not recall exactly what the assigned heading was. The altitude, I believe, was assigned as either 1600 ft MSL or 2000 ft MSL. I do know, beyond any doubt, however, there was no deviation on our part from assigned altitude and heading. Suddenly, I saw an aircraft at our 2-3 O'clock position. He suddenly turned sharply towards us (he made a left turn). Initially (before the abrupt maneuver) he seemed to be flying parallel to us. I was momentarily blinded by other aircraft's headlight. He missed us by approximately 200 ft. I estimate, from the moment I saw the other aircraft to the near mishap, it was no more than 30 seconds, possibly even shorter. Our aircraft was well lit. We used navigation lights, beacon, strobes and 2 landing/taxi lights. I was never informed or notified by ATC about the presence or proximity of other aircraft. Furthermore, I scanned for traffic. Immediately after the occurrence, I reported the event to the controller, who immediately explained that the other aircraft's pilot must have gotten confused. I do not recall any conversation between the pilot of the other aircraft or any approach controller. I believed he could have been on the north frequency. As I mentioned earlier, our flight was an IFR instructional flight during which I paid particular attention to my student's strict adherence of ATC instructions. We did not deviation from assigned altitude, heading or any other instruction issued by ATC. I was never provided with adequate IFR separation from another aircraft, which I learned later was also on IFR flight plan. When I was vectored on final, later on during the same approach, the controller was apologetic and expressed what seemed to me as general state of confusion experienced by ATC and possibly other aircraft. The following day, I was called by the tower representative and asked for detailed description. The control tower manager informed me that ATC made an error in vectoring on the night of the incident.

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Original NASA ASRS Text

Title: WHILE BEING VECTORED FOR AN ILS APCH, RPTR'S ACFT (X) CAME WITHIN CLOSE PROX OF ANOTHER ACFT (Y) THAT WAS ALSO BEING VECTORED BY DAB TRACON. THE SECOND ACFT (Y) WAS BEING WORKED BY A DIFFERENT CTLR ON ANOTHER FREQ. THIS RESULTED IN AN NMAC OPERROR.

Narrative: I WAS THE INSTRUCTING CFII ON AN INST (IFR FLT PLAN) XCOUNTRY FLT DAB-MLB-DAB. ON THE WAY BACK TO DAB, WE REQUESTED ILS RWY 7L TO DAB. WHILE OUR ACFT WAS BEING VECTORED DOWNWIND (S SIDE OF LOC) MY STUDENT FLEW, AS ASSIGNED BY ATC, WESTERLY HDG. I DO NOT RECALL EXACTLY WHAT THE ASSIGNED HDG WAS. THE ALT, I BELIEVE, WAS ASSIGNED AS EITHER 1600 FT MSL OR 2000 FT MSL. I DO KNOW, BEYOND ANY DOUBT, HOWEVER, THERE WAS NO DEV ON OUR PART FROM ASSIGNED ALT AND HDG. SUDDENLY, I SAW AN ACFT AT OUR 2-3 O'CLOCK POS. HE SUDDENLY TURNED SHARPLY TOWARDS US (HE MADE A L TURN). INITIALLY (BEFORE THE ABRUPT MANEUVER) HE SEEMED TO BE FLYING PARALLEL TO US. I WAS MOMENTARILY BLINDED BY OTHER ACFT'S HEADLIGHT. HE MISSED US BY APPROX 200 FT. I ESTIMATE, FROM THE MOMENT I SAW THE OTHER ACFT TO THE NEAR MISHAP, IT WAS NO MORE THAN 30 SECONDS, POSSIBLY EVEN SHORTER. OUR ACFT WAS WELL LIT. WE USED NAV LIGHTS, BEACON, STROBES AND 2 LNDG/TAXI LIGHTS. I WAS NEVER INFORMED OR NOTIFIED BY ATC ABOUT THE PRESENCE OR PROX OF OTHER ACFT. FURTHERMORE, I SCANNED FOR TFC. IMMEDIATELY AFTER THE OCCURRENCE, I RPTED THE EVENT TO THE CTLR, WHO IMMEDIATELY EXPLAINED THAT THE OTHER ACFT'S PLT MUST HAVE GOTTEN CONFUSED. I DO NOT RECALL ANY CONVERSATION BTWN THE PLT OF THE OTHER ACFT OR ANY APCH CTLR. I BELIEVED HE COULD HAVE BEEN ON THE N FREQ. AS I MENTIONED EARLIER, OUR FLT WAS AN IFR INSTRUCTIONAL FLT DURING WHICH I PAID PARTICULAR ATTN TO MY STUDENT'S STRICT ADHERENCE OF ATC INSTRUCTIONS. WE DID NOT DEV FROM ASSIGNED ALT, HDG OR ANY OTHER INSTRUCTION ISSUED BY ATC. I WAS NEVER PROVIDED WITH ADEQUATE IFR SEPARATION FROM ANOTHER ACFT, WHICH I LEARNED LATER WAS ALSO ON IFR FLT PLAN. WHEN I WAS VECTORED ON FINAL, LATER ON DURING THE SAME APCH, THE CTLR WAS APOLOGETIC AND EXPRESSED WHAT SEEMED TO ME AS GENERAL STATE OF CONFUSION EXPERIENCED BY ATC AND POSSIBLY OTHER ACFT. THE FOLLOWING DAY, I WAS CALLED BY THE TWR REPRESENTATIVE AND ASKED FOR DETAILED DESCRIPTION. THE CTL TWR MGR INFORMED ME THAT ATC MADE AN ERROR IN VECTORING ON THE NIGHT OF THE INCIDENT.

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.