Incident Overview
On October 22, 2014, at 0625 eastern daylight time, a Cirrus SR22 (registration N242MB) deployed its Cirrus Airframe Parachute System (CAPS) following a total loss of engine power. The commercial pilot was not injured, and the airplane sustained minor damage. Visual meteorological conditions prevailed for the personal flight conducted under Title 14 Code of Federal Regulations Part 91. The flight, operating under instrument flight rules, originated from Mc Gee Field Airport (24NC) in Monroe, North Carolina, at 0600 central daylight time and was destined for Piedmont Triad International Airport (GSO) in Greensboro, North Carolina.
Pilot Account
According to the pilot, while en route to the destination at a cruise altitude of 5,000 feet mean sea level, he contacted GSO approach and opened his flight plan. Shortly thereafter, the engine failed. The pilot flew the airplane towards an open field and deployed the CAPS system, resulting in a successful landing in the field.
Engine Examination
Examination of the engine revealed that the crankshaft had fractured between the number two main journal and the number two connecting rod journal. The number two bearing displayed bearing shift signatures and had completely extruded from the bearing support. The number one, two, three, and four bearing supports exhibited fretting near the through bolt holes. There was no evidence of oil starvation or lack of lubrication. The oil pump was intact; the drive gear showed no anomalies, and the oil pump cavity contained light scratches. The oil pressure relief valve seat contained some metallic debris, and the relief valve plate displayed signs of peened imprints around the seat area circumference.
The oil filter was removed and examined. The filter element contained flakes and slivers from damaged internal engine components. The oil sump plug was removed, and the oil was drained; 8 quarts of dark-colored oil containing metallic debris were measured. The oil sump was removed, revealing sections of bearing, metallic slivers, and shavings. The oil pickup tube was bent, and the screen was intact with metallic debris noted.
Maintenance Background
A review of maintenance records indicated that the Continental IO-550N7 engine was rebuilt by Teledyne Continental Motors on August 22, 2011. The engine had accumulated 775 hours since factory rebuild, and there was no record or evidence of the cylinders being removed since rebuild. The engine had accumulated 200 hours since the last annual inspection dated November 8, 2013. Additionally, a 50-hour engine oil change was performed 69 hours prior to the accident on September 29, 2014.
Metallurgical Analysis
The crankshaft was sent to the NTSB materials laboratory for fracture analysis. Examination revealed that the fracture was due to fatigue that initiated from multiple origins at the fillet radius between the second main journal and the cheek at the aft end of the journal.