WPR12LA406

The commercial pilot reported that, shortly after taking off for the personal flight, he heard a "pop" sound emanate from the engine, followed by a loss of engine power and subsequent loss of lift. The pilot maintained level forward flight until the airplane impacted an orchard. A postimpact fire ensued, and the airplane was partially consumed. The remainder of the airplane and the engine sustained thermal damage. An examination of the airframe and engine revealed no mechanical anomalies that would have precluded normal operation.

HISTORY OF FLIGHT On September 8, 2012 about 1215 Pacific daylight time, an Aviat Aircraft, Inc., A-1B, N395AA, experienced a loss of engine power immediately after takeoff from a lake, and conducted a forced landing into an orchard near Durham, California. The commercial pilot and one passenger received minor injuries; the airplane sustained substantial damage in the postcrash fire. The personal flight was operated under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed, and no flight plan had been filed. According to the pilot's written statement, the engine start and run-up were normal. Shortly after takeoff, he heard a "pop" sound, followed by the loss of power. The pilot continued straight ahead, and the airplane impacted in an orchard adjacent to the lake. He and his passenger observed a fire that had begun after impact, and evacuated the airplane. PERSONNEL INFORMATION Federal Aviation Administration (FAA) records indicated that the pilot held a commercial pilot certificate with airplane single and multi-engine land, single engine sea, and instrument airplane ratings. According to information provided by the pilot, he had approximately 1,325 total hours of flight experience, which included approximately 133 hours in the accident airplane make and model. His most recent flight review was completed in December 2011, and his most recent FAA third-class medical certificate was issued in March 2011. AIRCRAFT INFORMATION FAA records indicated that the airplane was manufactured in 2007, and was equipped with a Lycoming O-360 series engine. The pilot reported that the airplane had accumulated 292 hours in service at the time of its most recent annual inspection, which was completed in January 2012. METEOROLOGICAL INFORMATION According to information provided by the pilot, the skies were clear, winds were light and variable, and the visibility was 25 miles. The 1154 automated weather observation at Chico Municipal airport (CIC), Chico, California, located about 7.3 miles north-northwest of the accident location, included wind from 220 degrees at 5 knots, visibility 25 miles, few clouds at 5,000 and 15,000 feet, temperature 28 degrees C, dew point 11 degrees C, and an altimeter setting of 29.98 inches of mercury. AIRPORT INFORMATION The departure lake was a man-made body of water that measured approximately 2,100 by 200 feet, with the long axis oriented east-west. Elevation was approximately 200 feet above mean sea level. The lake was located about 7.3 miles, on a true heading of 154 degrees, from Chico Municipal Airport (CIC), Chico. TESTS AND RESEARCH INFORMATION Examination of the recovered airframe and engine was conducted on September 28, 2012, at the facilities of Plain Parts, Pleasant Grove, California. No evidence of preimpact mechanical malfunction was noted during the examination of the recovered airframe and engine. The airplane was a fabric covered Aviat Aircraft, Inc., Model A-1B,serial number 2395; the fabric had been consumed in the post-crash fire. The frame itself remained. Flight control continuity was established through all of the primary flight control surfaces by tracing the cables from the cockpit to the tail section and to wings. The engine was a four-cylinder Lycoming O-360-A1B, serial number L-40758-36E. The engine remained attached to the airframe via the engine mounts, and the propeller assembly remained attached to the engine. The entire engine had sustained varying degrees of thermal damage/consumption as a result of the postcrash fire. Manual rotation of the engine produced mechanical and drive train continuity, and thumb compression was obtained at all cylinders. Both magnetos remained attached to their respective mounting pads on the engine; they had sustained thermal damage and were not tested. The P-leads remained attached to the magneto cap. However, the P-leads had sustained thermal damage as a result of the postcrash fire. According to the Champion Aviation check-a-plug chart AV-27, the spark plugs electrodes exhibited a worn out – normal condition.