Narrative:

I was on an IFR flight crg-medium large transport at 6000 ft, orl approach control. At approximately 30 mi out, I asked for a lower altitude. Then, about 20 mi out, I asked center if it would be easier for them if I could cancel IFR. The controller said radar service terminated, frequency change approved. I called daytona approach control. He gave me a transponder code and said he had no radar contact, then he said he had a target 5 mi out, and I told him it was me. He then turned me over to tower. He told me to report a 2 mi left base over the interstate (he was very busy). When I got a chance to talk, I was turning final at 2 mi. He then asked if I was sure I was lined up with runway 9L. I said yes, about 1 mi final. He said I had overtaken another airplane on final. I did not see the airplane. The other pilot said that I had passed over top of them at 10 ft. My passenger told me later that he saw the other airplane on the lower right side of our airplane. My transponder was working for everyone except daytona approach and mlb tower. I think he gave me a wrong code or I put the wrong code in my transponder. Plus a very congested 2 runways, same direction.

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Original NASA ASRS Text

Title: NMAC BTWN AN SMA ON FINAL AT 300 FT AND ANOTHER ACFT 10 FT LOWER ALSO ON FINAL WHICH HAD BEEN OVERTAKEN BY RPTR.

Narrative: I WAS ON AN IFR FLT CRG-MLG AT 6000 FT, ORL APCH CTL. AT APPROX 30 MI OUT, I ASKED FOR A LOWER ALT. THEN, ABOUT 20 MI OUT, I ASKED CTR IF IT WOULD BE EASIER FOR THEM IF I COULD CANCEL IFR. THE CTLR SAID RADAR SVC TERMINATED, FREQ CHANGE APPROVED. I CALLED DAYTONA APCH CTL. HE GAVE ME A XPONDER CODE AND SAID HE HAD NO RADAR CONTACT, THEN HE SAID HE HAD A TARGET 5 MI OUT, AND I TOLD HIM IT WAS ME. HE THEN TURNED ME OVER TO TWR. HE TOLD ME TO RPT A 2 MI L BASE OVER THE INTERSTATE (HE WAS VERY BUSY). WHEN I GOT A CHANCE TO TALK, I WAS TURNING FINAL AT 2 MI. HE THEN ASKED IF I WAS SURE I WAS LINED UP WITH RWY 9L. I SAID YES, ABOUT 1 MI FINAL. HE SAID I HAD OVERTAKEN ANOTHER AIRPLANE ON FINAL. I DID NOT SEE THE AIRPLANE. THE OTHER PLT SAID THAT I HAD PASSED OVER TOP OF THEM AT 10 FT. MY PAX TOLD ME LATER THAT HE SAW THE OTHER AIRPLANE ON THE LOWER R SIDE OF OUR AIRPLANE. MY XPONDER WAS WORKING FOR EVERYONE EXCEPT DAYTONA APCH AND MLB TWR. I THINK HE GAVE ME A WRONG CODE OR I PUT THE WRONG CODE IN MY XPONDER. PLUS A VERY CONGESTED 2 RWYS, SAME DIRECTION.

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.