Narrative:

Student and I (CFI) were in pattern doing touch-and-goes. Informed unicom (it is an uncontrolled airport) that we would remain in pattern. There was 1 other aircraft in the pattern as well. There was a ground unit on the ground calling position reports while driving around the airport. When a call came over that was inaudible, I believed it was the ground unit, as he had been making calls (probably about 4) while we were flying the pattern. We had been making regular position reports to keep track of the other traffic in the pattern. While on downwind for what would have been our 7TH landing, we called downwind. At about the time a base leg would be started, a simulated engine out was begun by me. My student began his procedures while I checked the final leg for traffic. I did not see any. My student continued the approach, and when we had the runway made, began a forward slip to lose altitude. At about 60 ft AGL, I saw a plane pass underneath us on final approach. I immediately initiated a go around and we landed without further incident. Actions that I feel would have made a difference by myself would have been to call final, simulated engine failure. I feel that the other pilot could have made a difference by making more radio calls and entering the pattern on a 45 degree to either upwind or downwind. Upon landing, I contacted unicom, who told me that the aircraft had made a call that was barely audible, and that he never declared himself in the pattern. I realize the radio calls are a courtesy to an uncontrolled airport, but I feel this would have made a difference. Also, perhaps a better scan by all involved may have made even more of a difference.

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Original NASA ASRS Text

Title: FLT INSTRUCTION ACFT HAS AN NMAC AT UNCTLED ARPT.

Narrative: STUDENT AND I (CFI) WERE IN PATTERN DOING TOUCH-AND-GOES. INFORMED UNICOM (IT IS AN UNCTLED ARPT) THAT WE WOULD REMAIN IN PATTERN. THERE WAS 1 OTHER ACFT IN THE PATTERN AS WELL. THERE WAS A GND UNIT ON THE GND CALLING POS RPTS WHILE DRIVING AROUND THE ARPT. WHEN A CALL CAME OVER THAT WAS INAUDIBLE, I BELIEVED IT WAS THE GND UNIT, AS HE HAD BEEN MAKING CALLS (PROBABLY ABOUT 4) WHILE WE WERE FLYING THE PATTERN. WE HAD BEEN MAKING REGULAR POS RPTS TO KEEP TRACK OF THE OTHER TFC IN THE PATTERN. WHILE ON DOWNWIND FOR WHAT WOULD HAVE BEEN OUR 7TH LNDG, WE CALLED DOWNWIND. AT ABOUT THE TIME A BASE LEG WOULD BE STARTED, A SIMULATED ENG OUT WAS BEGUN BY ME. MY STUDENT BEGAN HIS PROCS WHILE I CHKED THE FINAL LEG FOR TFC. I DID NOT SEE ANY. MY STUDENT CONTINUED THE APCH, AND WHEN WE HAD THE RWY MADE, BEGAN A FORWARD SLIP TO LOSE ALT. AT ABOUT 60 FT AGL, I SAW A PLANE PASS UNDERNEATH US ON FINAL APCH. I IMMEDIATELY INITIATED A GAR AND WE LANDED WITHOUT FURTHER INCIDENT. ACTIONS THAT I FEEL WOULD HAVE MADE A DIFFERENCE BY MYSELF WOULD HAVE BEEN TO CALL FINAL, SIMULATED ENG FAILURE. I FEEL THAT THE OTHER PLT COULD HAVE MADE A DIFFERENCE BY MAKING MORE RADIO CALLS AND ENTERING THE PATTERN ON A 45 DEG TO EITHER UPWIND OR DOWNWIND. UPON LNDG, I CONTACTED UNICOM, WHO TOLD ME THAT THE ACFT HAD MADE A CALL THAT WAS BARELY AUDIBLE, AND THAT HE NEVER DECLARED HIMSELF IN THE PATTERN. I REALIZE THE RADIO CALLS ARE A COURTESY TO AN UNCTLED ARPT, BUT I FEEL THIS WOULD HAVE MADE A DIFFERENCE. ALSO, PERHAPS A BETTER SCAN BY ALL INVOLVED MAY HAVE MADE EVEN MORE OF A DIFFERENCE.

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.