LAX97LA212

Immediately after takeoff from the 2,400 foot dirt strip, the pilot made a 45-degree turn to avoid power lines that angled past the departure end of the runway. After clearing a road adjacent to the lines, the airplane settled. Subsequently, the landing gear was sheared off on the berm of an irrigation ditch, then the airplane came to rest inverted in a field beyond the ditch. Postaccident investigation revealed evidence of the carburetor being loose on the engine. The economizer link and the pump link were found to be in a 'high time condition since overhaul.' A flow test of the carburetor was conducted, but a determination of a proper fuel flow could not be established due to the extent of damage to the carburetor. No other preexisting anomalies were found with the engine.

On June 16, 1997, at 1130 hours Pacific daylight time, a Schweizer G-164B, N3631G, struck a berm after takeoff from an agricultural strip in Rio Linda, California. The aircraft was operated by Farm Air Flying Service under 14 CFR Part 137 as an agricultural crop dusting operation. The aircraft was substantially damaged, and the commercial rated pilot, the sole occupant, was seriously injured. Visual meteorological conditions existed for the flight that was originating at the time of the accident and the temperature was reported to be 81 degrees. No flight plan was filed.

An Federal Aviation Administration (FAA) inspector from the Sacramento, California, Flight Standards District Office, responded to the accident site. He reported that immediately after liftoff from the 2,400-foot-long dirt runway, the pilot had to make a 45-degree turn to avoid 150-foot power lines at the departure end. Immediately beyond the power lines was a road and an irrigation ditch. The aircraft's landing gear collided with the far edge of the ditch and sheared off the aircraft. The aircraft came to rest inverted beyond the ditch in a field.

The operator of the aircraft reported that there were approximately 2,400 pounds of chemicals onboard and no record of the amount of fuel.

The pilot stated that he was unable to recall any of the events after the takeoff roll.

The engine was examined at by the Safety Board and an FAA inspector at Clarksburg Air Repair in Sacramento. Postexamination revealed that the carburetor was loose on its mounting pad and had chafing and fretting signatures on it's mounting flange. It was also noted that the idle adjustment mixture control for the carburetor was set at full rich.

The carburetor was inspected at Aero-Engines, Inc., in Los Angeles, California, on August 25, 1997. The chief inspector reported that the carburetor showed evidence of being loose on the engine. The economizer link and the pump link were found to be in a "high time condition since overhaul." The testing facility determined that all the other internal parts of the carburetor appeared to be normal. A fuel flow test was conducted, but a determination of a proper fuel flow could not be established due to the extent of the damage to the carburetor.