ERA16LA076

The sport pilot was conducting a cross-country flight in the light sport airplane when, after about one hour of flight, the engine first experienced a partial loss of power, followed shortly thereafter by a total loss of power. The pilot twice unsuccessfully attempted to restart the engine using the emergency checklist before performing a forced landing to a field. During the landing, the airplane sustained substantial damage to the fuselage. The engine was manufactured about 10 years before the accident and maintenance logs indicated that it had not been overhauled since that time. Examination of the engine revealed that connecting rod bearing material was distributed throughout the power take off (PTO) section of the engine. Furthermore, corrosion was noted on the PTO connecting rod and connecting rod bearing. Although the engine had not yet reached the manufacturer's recommended 300 flight hour time limit for overhaul, it had exceeded the recommended 5-year calendar time limit for overhaul by 5 years. It is likely that a piece of the failed bearing became lodged in the rotary valve disc, which prevented the disc from rotating, and subsequently blocked the air and fuel to the engine, which resulted in a total loss of engine power. Had the engine been overhauled, the corrosion likely would have been discovered and the inflight loss of power prevented.

On December 19, 2015, about 1120 Atlantic standard time, an experimental amateur-built Rans S-12XL, N124LP, was substantially damaged during a forced landing following a total loss of engine power near Guanica, Puerto Rico. The sport pilot was not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the flight, which originated from Dr. Hermenegildo Ortiz Quinones Airport (X63), Humacao, Puerto Rico, about 1015, and was destined for Eugenio Maria de Hostos Airport (TJMZ), Mayaguez, Puerto Rico. The personal flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 91.According to the pilot, he performed a preflight and engine run-up with no anomalies noted. He flew the airplane for about an hour before the engine "sounded weird," then began to lose power, until it lost power completely. The pilot unsuccessfully attempted to restart the engine two times using the emergency checklist prior to preforming a forced landing to a field. During the landing, the airplane incurred substantial damage to the fuselage. According to Federal Aviation Administration records, the airplane was manufactured in 2009 and registered the pilot in May 2015. It was equipped with a Rotax 582 series engine that was manufactured in 2005. According to airplane maintenance logbooks, the most recent 100-hour inspection was completed on September 26, 2015, and at that time, the airplane had accumulated 213 hours of total time. According to the manufacturer's guidance, a general overhaul of the engine was "to be carried out every five years or every 300 hours, whichever comes first." There were no entries in the maintenance logs that indicated an engine overhaul had taken place. According to the checklist from the maintenance manual, which was the checklist that the mechanic initialed as items accomplished, item 38 "General overhaul of engine" was marked as "N/A." A manufacturer representative indicated that an overhaul consisted of at least a complete engine teardown, the replacement of all bearings, seals, gaskets, crankshaft, and piston rings. An examination of the engine revealed that there was fuel noted in the fuel tanks, fuel pump, fuel filter, and both carburetors. One spark plug was removed from each cylinder and thumb compression was obtained from all cylinders. However, when the propeller was rotated by hand, a metal scraping sound was heard. The engine oil was drained and metal particles were noted in the oil. The tachometer in the cockpit indicated 228 total hours of time. The engine was further examined and the power take off intake had several pieces of bearing material, and one piece specifically that was contacting the rotary valve disc, which was making the scraping noise. In addition, the bearing material was noted in the combustion chamber and exhaust sections of the power take off side of the engine. The cylinder head of the power take off side was removed and revealed damage to the piston head.Next, the power take off cylinder was removed. Corrosion and damage was noted on the connecting rod and the fractured connecting rod bearing.