Narrative:

On initial approach to bend airport our helicopter was making radio calls on CTAF (123.00) that we would be crossing mid field for a right downwind 34 (this is an established procedure that has not yet been put into the AFD) at one mile my student and I saw the glider under its own power (electric motor deployed) in the left downwind for 34. I instructed my student to turn left and cross behind the traffic. As soon as we started to do this the glider started to turn out to the west. I made a radio call to the glider specifically at this point and received no answer. I had my student turn more to the north to ensure that the glider would pass by our right. The glider continued to turn at our altitude toward us as we started to descend I made another radio call to the glider trying to talk to it. At this point I lost sight of the glider because my aircraft was obscuring it. I asked my student where it was at and he replied 'he's right there he's still turning toward us.' I allowed my student to continue to descend and was probably 200 ft AGL or less when I saw the glider appear over the top of my aircraft through the window installed on the top. The whole time we had been trying to turn in behind the glider who was obviously circling (obvious now) in the downwind without radios. When I saw the glider through the top window I took control and straightened out putting us in the left downwind. There was no tow plane as the glider was still under its own power. I know this because we passed near enough to hear the engine/prop.

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Original NASA ASRS Text

Title: R22 instructor pilot experiences a NMAC with a powered glider in the BDN traffic pattern. The glider was apparently thermaling with no intent to land and was not using radios.

Narrative: On Initial Approach to Bend Airport our Helicopter was making radio calls on CTAF (123.00) that we would be crossing mid field for a right downwind 34 (this is an established procedure that has not yet been put into the AFD) at one mile my student and I saw the glider under its own power (electric motor deployed) in the left downwind for 34. I instructed my student to turn left and cross behind the traffic. As soon as we started to do this the glider started to turn out to the west. I made a radio call to the glider specifically at this point and received no answer. I had my student turn more to the north to ensure that the glider would pass by our right. The glider continued to turn at our altitude toward us as we started to descend I made another radio call to the glider trying to talk to it. At this point I lost sight of the glider because my aircraft was obscuring it. I asked my student where it was at and he replied 'he's right there he's still turning toward us.' I allowed my student to continue to descend and was probably 200 FT AGL or less when I saw the glider appear over the top of my aircraft through the window installed on the top. The whole time we had been trying to turn in behind the glider who was obviously circling (obvious now) in the downwind without radios. When I saw the glider through the top window I took control and straightened out putting us in the left downwind. There was no tow plane as the glider was still under its own power. I know this because we passed near enough to hear the engine/prop.

Data retrieved from NASA's ASRS site 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.