Narrative:

I was returning from towing a banner (third of the day). I was calling my position and intention to drop the banner to the east of the runway. I crossed midfield and entered the downwind (banner in tow). Crossing midfield, I saw my drop zone. I saw the last banner I had dropped. I saw airplanes and cars on the edge of the field. I called at least 6 times on the unicom frequency and asked other aircraft to announce their position and reported my position each time and my intention to drop the banner to the east of the runway. There were 2 airplanes waiting at the end of the taxiway, preparing to depart. They both announced their position and intentions. There was no traffic in the pattern. I watched my drop zone when crossing midfield and downwind. On final to the drop zone, I kept the 2 aircraft on the taxiway in sight until I was clear of them. I made my drop in the field and turned to cross midfield to land. Turning, I could see that my banner had dropped just where I wanted it to. Right after I spotted my banner dropped, I heard an excited tirade from a helicopter pilot who stated that I had nearly dropped my banner on top of him. He made a narrow escape and called the FBO afterwards. I spoke to him and apologized, stating that he wasn't visible in the field when I was crossing midfield to downwind. He said that he had been taxiing/hovering (he didn't state his purpose) in the field. He also stated that his helicopter was dark blue and his rotating beacon would have been out of my view. I never heard him state his position or acknowledge my presence. I understand that an accident would have legally been my fault probably. I was unprepared to look for aircraft in the field. Helicopters use it regularly, but listen to the unicom for conflicts. I am always prepared to go around, but I could see no reason for concern. The airplane flies at 50 mph with banner in tow. I don't sneak up on anyone. Dark helicopters on or near the ground are very difficult to see.

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Original NASA ASRS Text

Title: HELI PLT ANNOUNCES OVER UNICOM THAT A BANNER DROPPED BY SUPER CUB JUST MISSED HIM DURING TAXI HOVER.

Narrative: I WAS RETURNING FROM TOWING A BANNER (THIRD OF THE DAY). I WAS CALLING MY POS AND INTENTION TO DROP THE BANNER TO THE E OF THE RWY. I CROSSED MIDFIELD AND ENTERED THE DOWNWIND (BANNER IN TOW). XING MIDFIELD, I SAW MY DROP ZONE. I SAW THE LAST BANNER I HAD DROPPED. I SAW AIRPLANES AND CARS ON THE EDGE OF THE FIELD. I CALLED AT LEAST 6 TIMES ON THE UNICOM FREQ AND ASKED OTHER ACFT TO ANNOUNCE THEIR POS AND RPTED MY POS EACH TIME AND MY INTENTION TO DROP THE BANNER TO THE E OF THE RWY. THERE WERE 2 AIRPLANES WAITING AT THE END OF THE TXWY, PREPARING TO DEPART. THEY BOTH ANNOUNCED THEIR POS AND INTENTIONS. THERE WAS NO TFC IN THE PATTERN. I WATCHED MY DROP ZONE WHEN XING MIDFIELD AND DOWNWIND. ON FINAL TO THE DROP ZONE, I KEPT THE 2 ACFT ON THE TXWY IN SIGHT UNTIL I WAS CLR OF THEM. I MADE MY DROP IN THE FIELD AND TURNED TO CROSS MIDFIELD TO LAND. TURNING, I COULD SEE THAT MY BANNER HAD DROPPED JUST WHERE I WANTED IT TO. RIGHT AFTER I SPOTTED MY BANNER DROPPED, I HEARD AN EXCITED TIRADE FROM A HELI PLT WHO STATED THAT I HAD NEARLY DROPPED MY BANNER ON TOP OF HIM. HE MADE A NARROW ESCAPE AND CALLED THE FBO AFTERWARDS. I SPOKE TO HIM AND APOLOGIZED, STATING THAT HE WASN'T VISIBLE IN THE FIELD WHEN I WAS XING MIDFIELD TO DOWNWIND. HE SAID THAT HE HAD BEEN TAXIING/HOVERING (HE DIDN'T STATE HIS PURPOSE) IN THE FIELD. HE ALSO STATED THAT HIS HELI WAS DARK BLUE AND HIS ROTATING BEACON WOULD HAVE BEEN OUT OF MY VIEW. I NEVER HEARD HIM STATE HIS POS OR ACKNOWLEDGE MY PRESENCE. I UNDERSTAND THAT AN ACCIDENT WOULD HAVE LEGALLY BEEN MY FAULT PROBABLY. I WAS UNPREPARED TO LOOK FOR ACFT IN THE FIELD. HELIS USE IT REGULARLY, BUT LISTEN TO THE UNICOM FOR CONFLICTS. I AM ALWAYS PREPARED TO GO AROUND, BUT I COULD SEE NO REASON FOR CONCERN. THE AIRPLANE FLIES AT 50 MPH WITH BANNER IN TOW. I DON'T SNEAK UP ON ANYONE. DARK HELIS ON OR NEAR THE GND ARE VERY DIFFICULT TO SEE.

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.