Narrative:

I was doing a one hour tour in a helicopter with 4 passengers, 1 pilot on board. Approximately 10 min into the flight I hit severe turbulence and was caught in a 8-10 second downdraft. These are common on the island. I lost about 400-500' of altitude. I was in a 3000' canyon. Since I lost altitude, I tried to use the 'updraft' on the west side of the canyon to climb. At the moment I was released from the downdraft and started to climb I was in a large saddle on the wall. There were old, copper telephone cables strung across the saddle with small poles. I struck the upper wire (which later the telephone company told me they float in the wind) on the upper part of the windscreen. I landed the aircraft, unloaded the passenger and shut down. There was minor damage (mostly scraped off paint) and a 12' piece of the wire was still wrapped around one of the pitch change links. Another aircraft picked up my passenger, and being an a/P mechanic I cleared the aircraft to fly back to the airfield with just myself on board. Wire was not on any maps. It was an old wire, not in use. Telephone company (who were notified) said wires float many ft during high winds. In the future I will increase my proximity to the surrounding terrain, horizontally. I was nearly 1400' AGL but due to the aircraft not having the power available to climb in stiff winds with heavy load made me use the updrafts of the canyon walls to get over.

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Original NASA ASRS Text

Title: HELICOPTER SIGHTSEEING TOUR. PLT EXPERIENCED DOWN DRAFT AND HIT TELEPHONE WIRES STRUNG ACROSS THE CANYON.

Narrative: I WAS DOING A ONE HR TOUR IN A HELI WITH 4 PAXS, 1 PLT ON BOARD. APPROX 10 MIN INTO THE FLT I HIT SEVERE TURB AND WAS CAUGHT IN A 8-10 SEC DOWNDRAFT. THESE ARE COMMON ON THE ISLAND. I LOST ABOUT 400-500' OF ALT. I WAS IN A 3000' CANYON. SINCE I LOST ALT, I TRIED TO USE THE 'UPDRAFT' ON THE W SIDE OF THE CANYON TO CLB. AT THE MOMENT I WAS RELEASED FROM THE DOWNDRAFT AND STARTED TO CLB I WAS IN A LARGE SADDLE ON THE WALL. THERE WERE OLD, COPPER TELEPHONE CABLES STRUNG ACROSS THE SADDLE WITH SMALL POLES. I STRUCK THE UPPER WIRE (WHICH LATER THE TELEPHONE COMPANY TOLD ME THEY FLOAT IN THE WIND) ON THE UPPER PART OF THE WINDSCREEN. I LANDED THE ACFT, UNLOADED THE PAX AND SHUT DOWN. THERE WAS MINOR DAMAGE (MOSTLY SCRAPED OFF PAINT) AND A 12' PIECE OF THE WIRE WAS STILL WRAPPED AROUND ONE OF THE PITCH CHANGE LINKS. ANOTHER ACFT PICKED UP MY PAX, AND BEING AN A/P MECH I CLRED THE ACFT TO FLY BACK TO THE AIRFIELD WITH JUST MYSELF ON BOARD. WIRE WAS NOT ON ANY MAPS. IT WAS AN OLD WIRE, NOT IN USE. TELEPHONE COMPANY (WHO WERE NOTIFIED) SAID WIRES FLOAT MANY FT DURING HIGH WINDS. IN THE FUTURE I WILL INCREASE MY PROX TO THE SURROUNDING TERRAIN, HORIZLY. I WAS NEARLY 1400' AGL BUT DUE TO THE ACFT NOT HAVING THE PWR AVAILABLE TO CLB IN STIFF WINDS WITH HVY LOAD MADE ME USE THE UPDRAFTS OF THE CANYON WALLS TO GET OVER.

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.