History of Flight
On February 24, 2011, about 0145 central standard time, a Cessna T210M, registration N6149B, was substantially damaged during a forced landing following a loss of engine power in cruise flight near Independence, Missouri. The pilot executed a forced landing to a roadway. The airplane was operated by Flight Express Inc. under 14 Code of Federal Regulations Part 135 as an on-demand cargo flight. Night visual meteorological conditions prevailed, and no flight plan was filed. The pilot sustained minor injuries. The flight originated from St. Louis Downtown Airport in Cahokia, Illinois, about 0030, with an intended destination of Charles B. Wheeler Downtown Airport (MKC) in Kansas City, Missouri.
The pilot reported that while in cruise flight at 4,000 feet mean sea level, approximately 18 miles from the destination, the engine began to run rough and lose power. Smoke entered the cockpit, and engine oil covered the windshield. The engine ultimately lost all power. During the forced landing, the left wing struck a roadway bridge guard railing.
Personnel Information
The pilot held an airline transport pilot certificate with single- and multi-engine land airplane ratings, as well as a flight instructor certificate with single- and multi-engine and instrument airplane ratings. He was issued a first-class airman medical certificate on March 1, 2010. At the time of the accident, the pilot reported approximately 5,800 hours total flight time, with about 900 hours in Cessna 210 airplanes. His most recent flight review was completed on December 4, 2010.
Aircraft Information
The accident airplane was a 1978 Cessna T210M, serial number 21062694, configured with one pilot seat for cargo operations. It was powered by a 300-horsepower Continental Motors IO-550-P8B engine, serial number 821115-R. Total airframe time at the accident was 12,103.0 hours, with 88.3 hours since the most recent inspection. The engine had accumulated 1,303.5 hours. The most recent inspection was completed on January 3, 2011, at 12,014.7 hours total airframe time. An engine oil change was performed on January 31, 2011. Maintenance records indicated the engine was rebuilt by Continental Motors and installed on the airplane in March 2009.
Meteorological Information
Weather recorded at Charles B. Wheeler Downtown Airport (MKC), about 14 miles west of the accident site, at 0154, included wind from 030 degrees at 7 knots, 10 miles visibility, overcast clouds at 6,000 feet above ground level, temperature 5 degrees Celsius, dew point 1 degree Celsius, and altimeter 30.01 inches of mercury. At Lee’s Summit Municipal Airport (LXT), about 10 miles south-southwest of the accident site, conditions at 0153 were wind from 040 degrees at 7 knots, 10 miles visibility, overcast clouds at 5,000 feet above ground level, temperature 4 degrees Celsius, dew point 2 degrees Celsius, and altimeter 30.01 inches of mercury.
Wreckage and Impact Information
The airplane came to rest on a roadway after the forced landing. The left wing struck a guard railing, causing substantial damage: the lower left wing skin was cut across approximately the entire chord of the wing. Two impact cuts were located near the wingtip, and a third was near mid-span outboard of the pitot tube. Contact with the guard rail also damaged the wing substructure in the area of the skin damage.
Engine Examination
A teardown engine examination conducted under NTSB oversight revealed a crankcase opening approximately 4 inches by 8 inches forward of the No. 5 cylinder bore, extending above the No. 6 cylinder bore. The crankshaft was fractured between the No. 6 connecting rod journal and the No. 4 crankshaft main journal. The No. 4 main bearing was shifted within the crankcase saddle, and the No. 3 main bearing was fractured into multiple pieces, most recovered from the oil sump. The camshaft was fractured at two locations, and the No. 6 connecting rod bolts were fractured. The No. 6 connecting rod was deformed with gouges consistent with secondary mechanical damage. The No. 5 and No. 6 pistons exhibited damage consistent with secondary mechanical impact, with portions of the skirt areas separated from the pistons; piston fragments were found in the oil sump.
The crankshaft fracture surfaces displayed features consistent with fatigue initiating at the forward radius of the No. 6 connecting rod journal. Additional cracks were observed at the forward flank of the No. 3 main journal, forward flank of the No. 4 connecting rod journal, and aft flank of the No. 5 connecting rod journal. Camshaft fracture features were consistent with fatigue caused by reverse bending. Failure of the No. 6 connecting rod bolts was consistent with overstress.
Records indicated the No. 3 crankcase main saddle bearing diameter was originally oversize by 0.0017 inch. The crankcase was subsequently reconditioned by the manufacturer. Manufacturer engineering documentation stated that reconditioned saddle bores may exceed the specified limit by 0.002 inch within a 40-degree arc centered on the split line; outside that area the diameter must conform. Measurements showed oversize diameters at multiple locations. At a point 90 degrees to the split line, all saddle bore diameters were within specifications. At the No. 1, No. 4, and No. 5 saddle bores, one diameter measurement at the plus or minus 20-degree limit was oversized. At the No. 2 and No. 3 saddle bores, diameters were oversized at both plus and minus 20-degree limits. The maximum dimension, on the No. 3 bore, measured 2.8185 inches, 0.0015 inch over the dimensional limit.