SEA00LA078

After completing aerial application operations for the day, the pilot took off to the north on a private airstrip with an approaching thunderstorm cell and heavy rain in the area. During takeoff, winds in the area shifted to southwesterly at about 20 knots, gusting to 25 knots (a nearby weather observation station reported winds shifting from north-northwesterly at 10 knots at 1800 to southwesterly at 27 knots, gusting to 32 knots, at 1900.) The pilot was unable to maintain directional control and the aircraft ground-looped, collapsing its right main gear and damaging its right wing. The pilot reported that no mechanical failure or malfunction was involved.

On April 21, 2000, approximately 1745 Pacific daylight time, a Piper PA-36-300 agricultural aircraft, N82698, was substantially damaged in a ground loop on takeoff from a private airstrip near Lexington, Oregon. The commercial pilot-in-command of the aircraft was not injured in the accident. The pilot reported that visual meteorological conditions prevailed at the accident site, and no flight plan had been filed for the 14 CFR 91 positioning flight from the accident airstrip to the pilot's home airstrip, also near Lexington.

The pilot reported that having completed agricultural aerial application operations for the day, he took off to the north with a thunderstorm cell approaching and heavy rain at the accident site. He stated that during the takeoff, the aircraft encountered a "wind [shift] and change of direction." The pilot reported that he was unable to maintain directional control upon encountering the wind shift, and that the aircraft ground looped. During the ground loop, the aircraft's right main landing gear collapsed and its right wing was damaged. The pilot indicated that no mechanical failure or malfunction was involved in the accident.

The pilot, who reported he did not obtain a weather briefing for the flight, reported the accident area winds as southwesterly at 20 knots, gusting to 25 knots, and that the airstrip surface was wet pavement and grass, 2,000 feet long and 30 feet wide. In an 1800 hourly METAR observation, Pendleton, Oregon, reported clear skies, 10 statute miles visibility, and winds from 330 degrees true at 12 knots. A subsequent Pendleton special observation, issued at 1900, gave conditions there as: ceiling 7,500 feet broken, visibility 1 statute mile with thunderstorm and haze, and winds from 230 degrees true at 27 knots, gusting to 32 knots.