Narrative:

I was flying in the dc ADIZ at approximately 2000 ft MSL on a westerly heading. The controller called unidented traffic at 5100 ft MSL and asked if I could read the tail number. I did not see the traffic. Several mins later; I reported my destination airport in sight and asked to change to advisory frequency. The controller advised not to change frequency and asked if I could once again try to obtain a tail number on the unidented aircraft. He vectored me through a series of heading changes. When I finally saw the other aircraft; we were on a collision course. I initiated a course change to avoid the other aircraft. The controller obviously had no experience directing intercepts nor any sense for the distance at which one can read a tail number.

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Original NASA ASRS Text

Title: SMA PLT TRANSITIONING DC ADIZ IS VECTORED BY PCT TOWARD ANOTHER ACFT TO OBTAIN ID INFO RESULTING IN REQUIRED AVOIDANCE COURSE CHANGES.

Narrative: I WAS FLYING IN THE DC ADIZ AT APPROX 2000 FT MSL ON A WESTERLY HDG. THE CTLR CALLED UNIDENTED TFC AT 5100 FT MSL AND ASKED IF I COULD READ THE TAIL NUMBER. I DID NOT SEE THE TFC. SEVERAL MINS LATER; I RPTED MY DEST ARPT IN SIGHT AND ASKED TO CHANGE TO ADVISORY FREQ. THE CTLR ADVISED NOT TO CHANGE FREQ AND ASKED IF I COULD ONCE AGAIN TRY TO OBTAIN A TAIL NUMBER ON THE UNIDENTED ACFT. HE VECTORED ME THROUGH A SERIES OF HDG CHANGES. WHEN I FINALLY SAW THE OTHER ACFT; WE WERE ON A COLLISION COURSE. I INITIATED A COURSE CHANGE TO AVOID THE OTHER ACFT. THE CTLR OBVIOUSLY HAD NO EXPERIENCE DIRECTING INTERCEPTS NOR ANY SENSE FOR THE DISTANCE AT WHICH ONE CAN READ A TAIL NUMBER.

Data retrieved from NASA's ASRS site as of May 2009 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.