Narrative:

I was on an instrument training flight. My student was under the hood. We were coming back from tamiami airport in miami, fl. We were on an IFR flight plan. We were doing an NDB approach into runway 8 in fxe. Miami approach had just handed us off to fxe tower. My student called up fxe tower to report that we had xed praiz and were inbound on the NDB approach. The tower responded that we should continue inbound. We told the tower that we were going to do a low approach only. We continued inbound on the NDB. At this point we had leveled off at the MDA, which was 740'. Before I knew it, I looked behind me and saw another small aircraft behind me. The aircraft was no further than 10' behind me. The aircraft turned to the left (my left) in order to avoid a mid-air collision. I then asked the tower if he wanted me to execute a missed approach, which I did. I am not sure how the small aircraft got so close behind me, but I do know that the tower did not warn me about the proximity of this other aircraft. This other aircraft was in a blind spot for me. The other aircraft was slightly higher and descending. (Traffic pattern altitude is 1000' MSL). Since I was level at the MDA, it was difficult for me to see the other aircraft. Fortunately, a mid-air collision was avoided, but it was too close.

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Original NASA ASRS Text

Title: PLT OF SMA ON TRAINING FLT ON NDB APCH TO FXE AT MDA 740' MSL HAD NMAC WITH ANOTHER SMA.

Narrative: I WAS ON AN INSTRUMENT TRNING FLT. MY STUDENT WAS UNDER THE HOOD. WE WERE COMING BACK FROM TAMIAMI ARPT IN MIAMI, FL. WE WERE ON AN IFR FLT PLAN. WE WERE DOING AN NDB APCH INTO RWY 8 IN FXE. MIAMI APCH HAD JUST HANDED US OFF TO FXE TWR. MY STUDENT CALLED UP FXE TWR TO RPT THAT WE HAD XED PRAIZ AND WERE INBND ON THE NDB APCH. THE TWR RESPONDED THAT WE SHOULD CONTINUE INBND. WE TOLD THE TWR THAT WE WERE GOING TO DO A LOW APCH ONLY. WE CONTINUED INBND ON THE NDB. AT THIS POINT WE HAD LEVELED OFF AT THE MDA, WHICH WAS 740'. BEFORE I KNEW IT, I LOOKED BEHIND ME AND SAW ANOTHER SMA BEHIND ME. THE ACFT WAS NO FURTHER THAN 10' BEHIND ME. THE ACFT TURNED TO THE LEFT (MY L) IN ORDER TO AVOID A MID-AIR COLLISION. I THEN ASKED THE TWR IF HE WANTED ME TO EXECUTE A MISSED APCH, WHICH I DID. I AM NOT SURE HOW THE SMA GOT SO CLOSE BEHIND ME, BUT I DO KNOW THAT THE TWR DID NOT WARN ME ABOUT THE PROX OF THIS OTHER ACFT. THIS OTHER ACFT WAS IN A BLIND SPOT FOR ME. THE OTHER ACFT WAS SLIGHTLY HIGHER AND DSNDING. (TFC PATTERN ALT IS 1000' MSL). SINCE I WAS LEVEL AT THE MDA, IT WAS DIFFICULT FOR ME TO SEE THE OTHER ACFT. FORTUNATELY, A MID-AIR COLLISION WAS AVOIDED, BUT IT WAS TOO CLOSE.

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.