N317KJ

On February 10, 2022, at 2006 central standard time, a Cirrus SR22T, N317KJ, sustained substantial damage when it was involved in an accident near Lincoln, Nebraska. The pilot and a passenger were uninjured. The airplane was operated as a Code of Federal Regulations Part 91 personal flight.

The pilot did not report any anomalies with the engine start, run-up, or takeoff. He reported the that the flight was initially uneventful, and the airplane was operating with all the gauges indicating within the proper operating limits. At 10,000 ft mean sea level (msl) and about 60 nm east of Lincoln Airport, Lincoln, Nebraska, there was a brief “stutter” of the engine, and the engine began to run rough. He contacted Omaha approach control and told them the engine was running rough and would like to divert to Plattsmouth Municipal Airport/Douglas V Duey Field (PMV), Plattsmouth, Nebraska, located about 39 nm and 080o from LNK.

The pilot said he a received clearance to fly direct to PMV and to descend and maintain 4,000 ft msl. About 40 nm miles from LNK and 8,000 ft msl, the pilot said he told Omaha approach control that the engine smoothed out, and he would like to continue the flight to LNK at 6,000 ft msl. The pilot said as the flight continued to LNK, the engine’s No. 3 cylinder head temperature indicated 0oF. About 15 nm east of LNK, the engine began to run rough again, and the pilot asked Omaha approach control if he could begin a slow descent toward LNK. He was cleared to descend and maintain 3,000 ft msl. About 12 nm from LNK, he was issued cleared for a visual approach to runway 17 and subsequently a clearance to land. As he continued the descent to 2,500 ft msl, the engine began to run rough, the oil pressure rapidly decreased, and the indicated airspeed decreased. About 6 nm from LNK, he told LNK air traffic control that he would be unable to make it to the runway and was going to look for a field to land on. He located a field, deployed the airframe parachute, and the airplane landed in the field and sustained substantial damage to the fuselage.

Recorded avionics data showed that about 1930, the airplane was about 100 nm from LNK and about 7 nm northeast of Schenck Field Airport, Clarinda, Iowa, at an altitude of about 10,000 ft when the No. 3 cylinder head temperature decreased to and remained about 210oF while the remaining cylinder head temperatures were about 300oF. The No. 3 cylinder had a corresponding decrease in exhaust gas temperature to about 600oF while the remaining cylinder exhaust gas temperatures remained about 1,300oF. These temperature indications remained constant to about 2007:30, at which time the temperatures further decreased to the end of recorded data at 2009:55. The continuous decrease in engine temperature corresponded to decreases in indicated airspeed and engine speed.

Postaccident examination of the engine revealed that the No. 3 cylinder, opposite to the No. 4 cylinder, was attached and secured to its crankpin. The cylinder exhibited debris related impact damage to an estimated 45o of the piston skirt bottom and nearest crank cheek.

The No. 4 cylinder connecting rod was detached from its crankpin at the connecting rod end. The end of the connecting rod was deformed and its connecting rod bolts and connecting rod cap were not intact. The No. 4 cylinder crankpin exhibited partial gouging along its circumference and radial impact related deformation.

The No. 5 piston and its connecting rod were intact and secure. The crankpin end of the No. 5 piston connecting rod was not connected to its crankpin, and the connecting rod end was hammered into a rounded shape. The connecting rod cap was not intact. The No. 5 cylinder crankpin did not exhibit scoring and did not possess gouging like that of the No. 4 cylinder crankpin.

The deformed end of a connecting rod with both connecting rod bolts in place was recovered loose in the engine.

The engine oil sump contained metallic debris, which was consistent with internal engine component failure, and engine oil.

The airplane engine logbook showed that on June 30, 2021, at a Hobbs time of 887.7 and a flight time of 790.0 hours, the No. 5 cylinder, part number 658595A1, serial number AC18FB740, was removed and replaced with a new cylinder, part number 658815A3, serial number AC21CA785. The engine logbook did not have entries for any subsequent engine cylinder removals.