Narrative:

A CFI and student were executing practice automatic-rotations in a r-hand pattern. We had executed 3 autos and had flared and were in a 3 ft hover when a shadow appeared over the helicopter. An unreadable voice on the CTAF was heard. The aircraft went around and continued touch-and-goes. There were 2 other aircraft departing. The aircraft that flew over us was advised that his radio was unreadable; but continued to do touch-and-goes. We departed the pattern and left the airport. We had cleared the area prior to each turn from downwind to base and base to final. We had been the only aircraft in the pattern and had been announcing all our prior automatic-rotations on the radio. The other aircraft never announced his presence or acknowledged that he had radio trouble.

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Original NASA ASRS Text

Title: A GOV MD500E; ON A TRAINING MISSION AT CTAF ARPT EXPERIENCED AN NMAC WITH A SINGLE NORDO C172 MAKING TOUCH-AND-GOES.

Narrative: A CFI AND STUDENT WERE EXECUTING PRACTICE AUTO-ROTATIONS IN A R-HAND PATTERN. WE HAD EXECUTED 3 AUTOS AND HAD FLARED AND WERE IN A 3 FT HOVER WHEN A SHADOW APPEARED OVER THE HELI. AN UNREADABLE VOICE ON THE CTAF WAS HEARD. THE ACFT WENT AROUND AND CONTINUED TOUCH-AND-GOES. THERE WERE 2 OTHER ACFT DEPARTING. THE ACFT THAT FLEW OVER US WAS ADVISED THAT HIS RADIO WAS UNREADABLE; BUT CONTINUED TO DO TOUCH-AND-GOES. WE DEPARTED THE PATTERN AND LEFT THE ARPT. WE HAD CLRED THE AREA PRIOR TO EACH TURN FROM DOWNWIND TO BASE AND BASE TO FINAL. WE HAD BEEN THE ONLY ACFT IN THE PATTERN AND HAD BEEN ANNOUNCING ALL OUR PRIOR AUTO-ROTATIONS ON THE RADIO. THE OTHER ACFT NEVER ANNOUNCED HIS PRESENCE OR ACKNOWLEDGED THAT HE HAD RADIO TROUBLE.

Data retrieved from NASA's ASRS site as of January 2009 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.