ERA16LA157

During a cross-country flight, the student pilot noticed the engine sputter and the engine rpm drop to 1,000. He pushed the mixture to its full rich position and pumped the throttle with no response from the engine. He then attempted to restart the engine to no avail and subsequently performed a forced landing on a highway. During the landing, the airplane impacted a tree, resulting in substantial damage. Postaccident examination of the engine revealed that the No. 6 connecting rod cap was fractured from fatigue that originated at the oil transfer hole in the center of the rod cap.

On April 14, 2016, about 1530 eastern daylight time, a Cessna 175, N6792E, was substantially damaged during a forced landing after a loss of engine power to a highway in Wartburg, Tennessee. The student pilot sustained minor injuries. Visual meteorological conditions prevailed, and no flight plan was filed for the instructional flight conducted under the provisions of Title 14 Code of Federal Regulations Part 91, which originated at Rockwood Municipal Airport (RKW), Rockwood, Tennessee, about 1500, destined for Williamsburg-Whitley County Airport (BYL), Williamsburg, Kentucky The purpose of the flight was for the student pilot to complete a solo cross-country flight. The student pilot stated he performed a preflight inspection and engine runup before departure. The takeoff and climb were normal, however shortly after leveling off at 3,500 ft above mean sea level, the engine began to sputter. Then while checking the fuel mixture and fuel gauges, engine rpm dropped to about 1,000. After attempting restart and unable to regain power to the engine, the pilot performed a forced landing on a highway. During the landing, the airplane struck and then came to rest against a tree. According to a first responder, there was fuel leaking from the airplane when emergency personnel arrived on scene. Photos provided by a Federal Aviation Administration inspector revealed that the airplane had incurred substantial damage. The right wing and engine were separated from the airplane; the outboard portion of the left wing was impact damaged, and the fuselage, and empennage, displayed impact damage. During an engine examination, it was noted that cylinders Nos. 2, 4, and 6 sustained impact damage. The crankcase was fractured between cylinders No. 5 and 6. The left and right magnetos produced spark at all leads when placed on a test stand. The spark plugs showed normal wear per the Champion aviation check-a-plug comparison chart. Fractured engine and metal components were found in the oil sump. Further examination of the engine revealed the No. 6 connecting rod cap was fractured. A metallurgical examination of the connecting rod cap revealed a fatigue fracture that originated at the oil transfer hole in the center of the rod cap. The closest weather reporting facility was Oak Ridge, Tennessee (OQT), about 18 miles east of the accident site. At 1453, weather included wind 110 at 5 knots; visibility 10 statute miles; clouds and sky condition, few at 5,000 ft; temperature, 22° C; dew point, 8° C; and a barometric altimeter setting of 30.13 inHg.