Narrative:

On final to runway 5 ZZZ approximately 800 ft MSL (600 ft AGL), I saw a helicopter coming straight towards me at approximately 500 ft MSL. As I started a climbing right turn I saw him make a right turn. I climbed to 1200 ft MSL and then made a climbing left turn to see where the helicopter was going. I was listening on CTAF and the helicopter never said a word. Approximately 2 mi ssw of the airport on a highway there was a bad wreck. The helicopter was an EMS and was landing at the accident site. I made one 360 degree turn around the accident site at 1300 ft MSL. During the turn I heard a student pilot report downwind runway 23. I then entered downwind runway 23 behind the student. When I was on final runway 23, the airport manager came on CTAF and said that the county sheriff had called and said that I had interfered with an emergency vehicle. I don't think I did anything wrong but the sheriff thinks I did. I am going to the FAA office on my day off (wed) and see if there is a regulation that I violated. I think EMS helicopters should make an announcement on CTAF when they are going through an airport traffic pattern and ask other aircraft to stay clear. If that had happened in this case I would have not got so close to the helicopter and I would not have turned to see where he was and where he was going.

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Original NASA ASRS Text

Title: SMA PLT ON FINAL APCH HAS NMAC WITH EMS HELI ENRTE TO AN ACCIDENT SCENE. BOTH TAKE EVASIVE ACTION. NON TWR ARPT.

Narrative: ON FINAL TO RWY 5 ZZZ APPROX 800 FT MSL (600 FT AGL), I SAW A HELI COMING STRAIGHT TOWARDS ME AT APPROX 500 FT MSL. AS I STARTED A CLBING R TURN I SAW HIM MAKE A R TURN. I CLBED TO 1200 FT MSL AND THEN MADE A CLBING L TURN TO SEE WHERE THE HELI WAS GOING. I WAS LISTENING ON CTAF AND THE HELI NEVER SAID A WORD. APPROX 2 MI SSW OF THE ARPT ON A HWY THERE WAS A BAD WRECK. THE HELI WAS AN EMS AND WAS LNDG AT THE ACCIDENT SITE. I MADE ONE 360 DEG TURN AROUND THE ACCIDENT SITE AT 1300 FT MSL. DURING THE TURN I HEARD A STUDENT PLT RPT DOWNWIND RWY 23. I THEN ENTERED DOWNWIND RWY 23 BEHIND THE STUDENT. WHEN I WAS ON FINAL RWY 23, THE ARPT MGR CAME ON CTAF AND SAID THAT THE COUNTY SHERIFF HAD CALLED AND SAID THAT I HAD INTERFERED WITH AN EMER VEHICLE. I DON'T THINK I DID ANYTHING WRONG BUT THE SHERIFF THINKS I DID. I AM GOING TO THE FAA OFFICE ON MY DAY OFF (WED) AND SEE IF THERE IS A REG THAT I VIOLATED. I THINK EMS HELIS SHOULD MAKE AN ANNOUNCEMENT ON CTAF WHEN THEY ARE GOING THROUGH AN ARPT TFC PATTERN AND ASK OTHER ACFT TO STAY CLR. IF THAT HAD HAPPENED IN THIS CASE I WOULD HAVE NOT GOT SO CLOSE TO THE HELI AND I WOULD NOT HAVE TURNED TO SEE WHERE HE WAS AND WHERE HE WAS GOING.

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.