Narrative:

I was acting as an instructor, performing a flight review for one of my partners in our mooney 231. We had entered a standard pattern at evy (45 degree entry, left downwind, base, final) for runway 35. I had not realized that my student was transmitting his calls on the wrong frequency of 122.8 (correct CTAF is 122.7). We heard no other traffic and I expected none, as it was a week day. I was, however, still vigilant, and had expressed to my student that he should look outside for traffic more often. As we crossed over the numbers we saw an airplane shadow cross perpendicular to the runway, and after taxiing off the active we saw another plane (the archer) circle at very low level and land. They pulled off facing us and the instructor came over to tell us that we had nearly collided. Clearly, a contributing factor was the incorrect CTAF frequency. I impress upon my students the importance of making frequent position reports. It does no good on the wrong frequency. The main factor, however, was not seeing the traffic that was there. There are NORDO aircraft that use this airport and just because an airplane does not call in does not mean the pattern is empty. Both the other instructor and I felt that no one else was around and although I was looking, I was not seeing. Afterwards, we discussed our flight paths. It looks like the mooney turned onto a longer final approach (my student was having a bit of trouble slowing the plane down so our downwind got extended) then the archer turned onto final directly above and behind us before spotting us. I'm always careful to check the final approach path before turning on final, but I have only been checking to the right (away from the airport). If I had looked to the left (checking between my position, and the airport) I might have seen the archer on base inside of our position (or still on downwind). I had impressed upon my student the importance of keeping his head out of the cockpit (he was spending a lot of time looking at the gauges). This lesson was far more real than I had planned.

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Original NASA ASRS Text

Title: NMAC BTWN A MOONEY M20 ON SHORT FINAL TO AN UNCTLED ARPT RWY AND A PIPER ARCHER THAT HAD TURNED FINAL APPROX THE SAME TIME JUST ABOVE THE MOONEY. THE ARCHER TOOK IMMEDIATE EVASIVE ACTION BY TURNING OUT TO AVOID THE MOONEY. THE MOONEY PLTS NEVER OBSERVED THE ARCHER, ONLY A SUSPICIOUS SHADOW.

Narrative: I WAS ACTING AS AN INSTRUCTOR, PERFORMING A FLT REVIEW FOR ONE OF MY PARTNERS IN OUR MOONEY 231. WE HAD ENTERED A STANDARD PATTERN AT EVY (45 DEG ENTRY, L DOWNWIND, BASE, FINAL) FOR RWY 35. I HAD NOT REALIZED THAT MY STUDENT WAS XMITTING HIS CALLS ON THE WRONG FREQ OF 122.8 (CORRECT CTAF IS 122.7). WE HEARD NO OTHER TFC AND I EXPECTED NONE, AS IT WAS A WK DAY. I WAS, HOWEVER, STILL VIGILANT, AND HAD EXPRESSED TO MY STUDENT THAT HE SHOULD LOOK OUTSIDE FOR TFC MORE OFTEN. AS WE CROSSED OVER THE NUMBERS WE SAW AN AIRPLANE SHADOW CROSS PERPENDICULAR TO THE RWY, AND AFTER TAXIING OFF THE ACTIVE WE SAW ANOTHER PLANE (THE ARCHER) CIRCLE AT VERY LOW LEVEL AND LAND. THEY PULLED OFF FACING US AND THE INSTRUCTOR CAME OVER TO TELL US THAT WE HAD NEARLY COLLIDED. CLRLY, A CONTRIBUTING FACTOR WAS THE INCORRECT CTAF FREQ. I IMPRESS UPON MY STUDENTS THE IMPORTANCE OF MAKING FREQUENT POS RPTS. IT DOES NO GOOD ON THE WRONG FREQ. THE MAIN FACTOR, HOWEVER, WAS NOT SEEING THE TFC THAT WAS THERE. THERE ARE NORDO ACFT THAT USE THIS ARPT AND JUST BECAUSE AN AIRPLANE DOES NOT CALL IN DOES NOT MEAN THE PATTERN IS EMPTY. BOTH THE OTHER INSTRUCTOR AND I FELT THAT NO ONE ELSE WAS AROUND AND ALTHOUGH I WAS LOOKING, I WAS NOT SEEING. AFTERWARDS, WE DISCUSSED OUR FLT PATHS. IT LOOKS LIKE THE MOONEY TURNED ONTO A LONGER FINAL APCH (MY STUDENT WAS HAVING A BIT OF TROUBLE SLOWING THE PLANE DOWN SO OUR DOWNWIND GOT EXTENDED) THEN THE ARCHER TURNED ONTO FINAL DIRECTLY ABOVE AND BEHIND US BEFORE SPOTTING US. I'M ALWAYS CAREFUL TO CHK THE FINAL APCH PATH BEFORE TURNING ON FINAL, BUT I HAVE ONLY BEEN CHKING TO THE R (AWAY FROM THE ARPT). IF I HAD LOOKED TO THE L (CHKING BTWN MY POS, AND THE ARPT) I MIGHT HAVE SEEN THE ARCHER ON BASE INSIDE OF OUR POS (OR STILL ON DOWNWIND). I HAD IMPRESSED UPON MY STUDENT THE IMPORTANCE OF KEEPING HIS HEAD OUT OF THE COCKPIT (HE WAS SPENDING A LOT OF TIME LOOKING AT THE GAUGES). THIS LESSON WAS FAR MORE REAL THAN I HAD PLANNED.

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.