Narrative:

The student had elected to file IFR and we were on the procedure turn outbnd. I was looking for traffic. I saw a low fixed wing aircraft small aircraft Y approaching approximately head-on at the same altitude. (Both student and myself had on headsets, but no intercom.) I informed approach of sighted aircraft and was told by approach control that the only target in area was at 3800' (we were at 2600' at the time), that we were now out of their radar range and to contact advisory frequency. The other aircraft passed off our left by about 300 to 500'. I heard my student say cancel IFR, and I noticed that he changed the squawk code to 1200. We completed the approach and landed. About an hour later, the student called FSS on the phone and was told to call approach control on the phone. He called and was told by approach control that he had failed to cancel the IFR, and that they had started a search for him. They asked for his home phone # and address. The student later told me that he had asked me whether he should cancel during the approach. Near miss was caused by an aircraft approaching an uncontrolled airport straight in and almost directly in line with the NAVAID serving the same runway while aircraft on approach is on approach frequency and cannot hear other aircraft on the advisory frequency. Possible failure to cancel was caused by misunderstanding response of the approach controller during near miss and difficulty of pilot and instrument communications when both wear headsets with no intercom.

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Original NASA ASRS Text

Title: INSTRUCTOR AND STUDENT ON IFR FLT PLAN AND CONDUCTING PRACTICE APCHS ARE TOLD TO CONTACT ADVISORY FREQ. THEY CONTINUE FOR A LNDG WITHOUT CANCELLING THEIR IFR. ADDITIONALLY, THEY ALSO HAVE AN NMAC. THE 2 EVENTS ARE NOT RELATED.

Narrative: THE STUDENT HAD ELECTED TO FILE IFR AND WE WERE ON THE PROC TURN OUTBND. I WAS LOOKING FOR TFC. I SAW A LOW FIXED WING ACFT SMA Y APCHING APPROX HEAD-ON AT THE SAME ALT. (BOTH STUDENT AND MYSELF HAD ON HEADSETS, BUT NO INTERCOM.) I INFORMED APCH OF SIGHTED ACFT AND WAS TOLD BY APCH CTL THAT THE ONLY TARGET IN AREA WAS AT 3800' (WE WERE AT 2600' AT THE TIME), THAT WE WERE NOW OUT OF THEIR RADAR RANGE AND TO CONTACT ADVISORY FREQ. THE OTHER ACFT PASSED OFF OUR LEFT BY ABOUT 300 TO 500'. I HEARD MY STUDENT SAY CANCEL IFR, AND I NOTICED THAT HE CHANGED THE SQUAWK CODE TO 1200. WE COMPLETED THE APCH AND LANDED. ABOUT AN HR LATER, THE STUDENT CALLED FSS ON THE PHONE AND WAS TOLD TO CALL APCH CTL ON THE PHONE. HE CALLED AND WAS TOLD BY APCH CTL THAT HE HAD FAILED TO CANCEL THE IFR, AND THAT THEY HAD STARTED A SEARCH FOR HIM. THEY ASKED FOR HIS HOME PHONE # AND ADDRESS. THE STUDENT LATER TOLD ME THAT HE HAD ASKED ME WHETHER HE SHOULD CANCEL DURING THE APCH. NEAR MISS WAS CAUSED BY AN ACFT APCHING AN UNCONTROLLED ARPT STRAIGHT IN AND ALMOST DIRECTLY IN LINE WITH THE NAVAID SERVING THE SAME RWY WHILE ACFT ON APCH IS ON APCH FREQ AND CANNOT HEAR OTHER ACFT ON THE ADVISORY FREQ. POSSIBLE FAILURE TO CANCEL WAS CAUSED BY MISUNDERSTANDING RESPONSE OF THE APCH CTLR DURING NEAR MISS AND DIFFICULTY OF PLT AND INSTR COMS WHEN BOTH WEAR HEADSETS WITH NO INTERCOM.

Data retrieved from NASA's ASRS site as of August 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.