Narrative:

I was giving an introduction flight. After takeoff, we turned in a northwest departure toward loveland and continued to climb up to 7000 ft. I leveled off at this altitude and demonstrated shallow turns. (We were over loveland at this time.) I then flew toward the south end, east side of horse tooth reservation and I proceeded to make a climbing left turn to the south, then east, and return to the airport, when under my raised right wing I saw an airplane making a sharp diving left turn toward the east. He proceeded on a southeast heading. I continued my turn toward the west then southeast. I was using my scan pattern at all times, but due to the fact the other aircraft was blending into the terrain I did not see him. I am unable to make recommendations at this time as to how to fix this problem. The other aircraft and PIC are known to me so when we landed I talked with the other pilot. He told me he didn't know what was occurring until his student cranked the airplane hard to the left.

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Original NASA ASRS Text

Title: AN INSTRUCTOR AND STUDENT IN A C172 HAVE AN NMAC WITH A C152 WHILE ENGAGED IN TRAINING. THE C152 STUDENT EVADED AND SAVED THE DAY.

Narrative: I WAS GIVING AN INTRODUCTION FLT. AFTER TKOF, WE TURNED IN A NW DEP TOWARD LOVELAND AND CONTINUED TO CLB UP TO 7000 FT. I LEVELED OFF AT THIS ALT AND DEMONSTRATED SHALLOW TURNS. (WE WERE OVER LOVELAND AT THIS TIME.) I THEN FLEW TOWARD THE S END, E SIDE OF HORSE TOOTH RESERVATION AND I PROCEEDED TO MAKE A CLBING L TURN TO THE S, THEN E, AND RETURN TO THE ARPT, WHEN UNDER MY RAISED R WING I SAW AN AIRPLANE MAKING A SHARP DIVING L TURN TOWARD THE E. HE PROCEEDED ON A SE HDG. I CONTINUED MY TURN TOWARD THE W THEN SE. I WAS USING MY SCAN PATTERN AT ALL TIMES, BUT DUE TO THE FACT THE OTHER ACFT WAS BLENDING INTO THE TERRAIN I DID NOT SEE HIM. I AM UNABLE TO MAKE RECOMMENDATIONS AT THIS TIME AS TO HOW TO FIX THIS PROB. THE OTHER ACFT AND PIC ARE KNOWN TO ME SO WHEN WE LANDED I TALKED WITH THE OTHER PLT. HE TOLD ME HE DIDN'T KNOW WHAT WAS OCCURRING UNTIL HIS STUDENT CRANKED THE AIRPLANE HARD TO THE L.

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.