History of Flight
On July 10, 2013, at approximately 0445 Pacific daylight time, a Raytheon Aircraft Company Beech A36, registration N517DJ, suffered a catastrophic engine failure during the initial climb after departing from Fallon Municipal Airport (FLX), Fallon, Nevada. The aircraft was being operated by Silver Sage Aviation under 14 Code of Federal Regulations Part 135 as a cross-country business flight destined for Dixie Valley, Nevada. Night visual meteorological conditions prevailed, and a visual flight rules flight plan had been filed.
The pilot reported that while climbing through about 1,000 feet above ground level, the engine lost power. He attempted to return to FLX but was unable to reach the airport, executing a forced landing in the desert adjacent to the field. The aircraft sustained substantial damage to the wings, fuselage, and empennage.
Aircraft and Engine Information
The airplane was a Beech A36, serial number E-3075. According to the operator, total airframe time at the accident was 1,294 hours. The last annual inspection occurred on June 26, 2013, at a tachometer reading of 1,280.1 hours. The tachometer at the accident scene indicated 1,298.7 hours.
The engine was a Continental Motors IO-550, serial number 281690-R. At the last 100-hour inspection, total engine time was 5,364.9 hours, with 282.3 hours since major overhaul.
Wreckage and Impact
The aircraft came to rest approximately 600 feet from the departure end of runway 03 on flat desert terrain. During recovery, a breach was noted in the engine case adjacent to the number five cylinder.
Examination and Testing
Investigators examined the wreckage at Air Transport in Phoenix, Arizona, on July 30, 2013. The airframe showed no mechanical anomalies. Examination of the engine revealed that the number five connecting rod cap and one of its bolts had fractured at midlength, while the opposite bolt remained intact with the nut still fastened. This failure led to a catastrophic breach on the left side of the engine case, between the number six and four cylinders.
No indications of oil starvation were found, and no assembly discrepancies were noted. The engine could be rotated, and continuity from front to rear was established. The aircraft was equipped with a JPI 800 engine monitoring system, which was downloaded by the NTSB laboratory; the data showed no abnormalities prior to the failure.
The number five and number six connecting rods, rod end caps, and bolts were sent to the NTSB materials laboratory. Examination determined that the fracture surfaces resulted from fatigue failure of the number five connecting rod.