Narrative:

I was giving instrument instruction to a student. We were practicing an NDB approach at an uncontrolled field and monitoring the approach controller who handles the approachs to this airport. He was completely overloaded with traffic at another airport and en route traffic, so we did not attempt to get radar service. I cleared my student direct to the NDB and cleared him for the approach. As we got close to the NDB, my student was having trouble. I had to scan the ADF (to instruct him) and scan outside. On one of my outside scans, my peripheral vision caught something wrong with my large blind spot. The door post on my side in front of me seemed to have something horizontal sticking out of it. When I moved my head to look, I saw an small aircraft coming directly at us. I banked the aircraft about 80 degrees to the left. I estimate that we passed about 50 ft away. The small aircraft never turned. We must have filled their windscreen with that 80 degree bank and I'm not sure they ever saw us. They were also at the wrong altitude for their direction of flight. I took my student away from the station for a few mins and cleared him to the NDB again. Since I didn't see the small aircraft turn after it passed the station, I didn't think they were using the NDB for navigation. But, as we approached the NDB, I saw the small aircraft on a converging course. I had my student continue tracking. I was hoping that the small aircraft would see us and deviation; we were ahead of them and technically had the right of way. When they got too close for my comfort, I turned to diverge slightly from their course to get their 'north' number. Suddenly they turned directly towards us. I applied full throttle and climbed. They passed below and behind us. I maneuvered the aircraft to try to get their 'north' number again, but it was too difficult to read. However, about 30 seconds later, the instructor's voice supplied the numbers on the approach frequency attempting to get radar service.

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Original NASA ASRS Text

Title: 2 VFR SMAS HAD A NMAC WHILE GIVING INSTRUCTION IN EXCELLENT VISIBILITY.

Narrative: I WAS GIVING INST INSTRUCTION TO A STUDENT. WE WERE PRACTICING AN NDB APCH AT AN UNCTLED FIELD AND MONITORING THE APCH CTLR WHO HANDLES THE APCHS TO THIS ARPT. HE WAS COMPLETELY OVERLOADED WITH TFC AT ANOTHER ARPT AND ENRTE TFC, SO WE DID NOT ATTEMPT TO GET RADAR SVC. I CLRED MY STUDENT DIRECT TO THE NDB AND CLRED HIM FOR THE APCH. AS WE GOT CLOSE TO THE NDB, MY STUDENT WAS HAVING TROUBLE. I HAD TO SCAN THE ADF (TO INSTRUCT HIM) AND SCAN OUTSIDE. ON ONE OF MY OUTSIDE SCANS, MY PERIPHERAL VISION CAUGHT SOMETHING WRONG WITH MY LARGE BLIND SPOT. THE DOOR POST ON MY SIDE IN FRONT OF ME SEEMED TO HAVE SOMETHING HORIZ STICKING OUT OF IT. WHEN I MOVED MY HEAD TO LOOK, I SAW AN SMA COMING DIRECTLY AT US. I BANKED THE ACFT ABOUT 80 DEGS TO THE L. I ESTIMATE THAT WE PASSED ABOUT 50 FT AWAY. THE SMA NEVER TURNED. WE MUST HAVE FILLED THEIR WINDSCREEN WITH THAT 80 DEG BANK AND I'M NOT SURE THEY EVER SAW US. THEY WERE ALSO AT THE WRONG ALT FOR THEIR DIRECTION OF FLT. I TOOK MY STUDENT AWAY FROM THE STATION FOR A FEW MINS AND CLRED HIM TO THE NDB AGAIN. SINCE I DIDN'T SEE THE SMA TURN AFTER IT PASSED THE STATION, I DIDN'T THINK THEY WERE USING THE NDB FOR NAV. BUT, AS WE APCHED THE NDB, I SAW THE SMA ON A CONVERGING COURSE. I HAD MY STUDENT CONTINUE TRACKING. I WAS HOPING THAT THE SMA WOULD SEE US AND DEV; WE WERE AHEAD OF THEM AND TECHNICALLY HAD THE RIGHT OF WAY. WHEN THEY GOT TOO CLOSE FOR MY COMFORT, I TURNED TO DIVERGE SLIGHTLY FROM THEIR COURSE TO GET THEIR 'N' NUMBER. SUDDENLY THEY TURNED DIRECTLY TOWARDS US. I APPLIED FULL THROTTLE AND CLBED. THEY PASSED BELOW AND BEHIND US. I MANEUVERED THE ACFT TO TRY TO GET THEIR 'N' NUMBER AGAIN, BUT IT WAS TOO DIFFICULT TO READ. HOWEVER, ABOUT 30 SECONDS LATER, THE INSTRUCTOR'S VOICE SUPPLIED THE NUMBERS ON THE APCH FREQ ATTEMPTING TO GET RADAR SVC.

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.