Narrative:

It was the first flight of the day and I was making the first pass on an alfalfa field when the aircraft struck wires. The field is a 50 acre parcel located west and adjoining the yard of his ranch residence. It is situated in a small valley floor about 1/4 mi wide, and about 25 road mi south of hermiston, or. The surrounding hills are steep and 300' to 400' higher than the creek bed. The valley lays southeast-northwest and a paved county road curves along the southern edge of the valley. A power line follows the road on the south side; a service line is strung from a pole on this line across the eastern portion of the alfalfa field nward to a power pole located out of the field and near a grove of trees. These are the wires that were struck. Control of the aircraft was not affected and there was no damage either to the aircraft or anything on the ground other than to the wires. Electrical service to the house and ranch buildings was interrupted until the wires could be repaired a few hours later. I was very surprised by the fact that I did not see the wires. I had surveyed the field from the air just before I started spraying and from the ground the day before, but did not observe them. Almost always there are visible clues that a line is present, even thought the wires themselves cannot be seen; but in this case I did not detect any. I feel that the time of day was also a factor. The bright yellow sunlight was shining on about half of the field (including the area where the wires are located) and the dark shadow of the hills covered the other half, making it difficult to see.

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Original NASA ASRS Text

Title: ACFT STRUCK POWER LINE WHILE SPRAYING AN ALFALFA FIELD.

Narrative: IT WAS THE FIRST FLT OF THE DAY AND I WAS MAKING THE FIRST PASS ON AN ALFALFA FIELD WHEN THE ACFT STRUCK WIRES. THE FIELD IS A 50 ACRE PARCEL LOCATED W AND ADJOINING THE YARD OF HIS RANCH RESIDENCE. IT IS SITUATED IN A SMALL VALLEY FLOOR ABOUT 1/4 MI WIDE, AND ABOUT 25 ROAD MI S OF HERMISTON, OR. THE SURROUNDING HILLS ARE STEEP AND 300' TO 400' HIGHER THAN THE CREEK BED. THE VALLEY LAYS SE-NW AND A PAVED COUNTY ROAD CURVES ALONG THE SOUTHERN EDGE OF THE VALLEY. A PWR LINE FOLLOWS THE ROAD ON THE S SIDE; A SVC LINE IS STRUNG FROM A POLE ON THIS LINE ACROSS THE EASTERN PORTION OF THE ALFALFA FIELD NWARD TO A PWR POLE LOCATED OUT OF THE FIELD AND NEAR A GROVE OF TREES. THESE ARE THE WIRES THAT WERE STRUCK. CTL OF THE ACFT WAS NOT AFFECTED AND THERE WAS NO DAMAGE EITHER TO THE ACFT OR ANYTHING ON THE GND OTHER THAN TO THE WIRES. ELECTRICAL SVC TO THE HOUSE AND RANCH BUILDINGS WAS INTERRUPTED UNTIL THE WIRES COULD BE REPAIRED A FEW HRS LATER. I WAS VERY SURPRISED BY THE FACT THAT I DID NOT SEE THE WIRES. I HAD SURVEYED THE FIELD FROM THE AIR JUST BEFORE I STARTED SPRAYING AND FROM THE GND THE DAY BEFORE, BUT DID NOT OBSERVE THEM. ALMOST ALWAYS THERE ARE VISIBLE CLUES THAT A LINE IS PRESENT, EVEN THOUGHT THE WIRES THEMSELVES CANNOT BE SEEN; BUT IN THIS CASE I DID NOT DETECT ANY. I FEEL THAT THE TIME OF DAY WAS ALSO A FACTOR. THE BRIGHT YELLOW SUNLIGHT WAS SHINING ON ABOUT HALF OF THE FIELD (INCLUDING THE AREA WHERE THE WIRES ARE LOCATED) AND THE DARK SHADOW OF THE HILLS COVERED THE OTHER HALF, MAKING IT 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.