Incident Summary
On February 22, 2018, a Cirrus SR22 (registration N325TE) departed Pompano Beach, Florida, at 12:30 pm local time, destined for Marsh Harbour, Abaco. While en route, the pilot noticed an oil sensor indication and suspected engine malfunction. He diverted to Deep Water Cay Airport, East Grand Bahama, and landed. After a telephone consultation with a mechanic, the pilot opted to depart again at 1:45 pm. Shortly after takeoff, the oil sensor indication returned and the engine failed. Unable to return to the airport, the pilot executed an emergency landing on a nearby dirt road. The aircraft sustained damage; no injuries were reported.
Aircraft and Pilot Information
The aircraft was a Cirrus SR22, a four-seat, low-wing, single-engine monoplane with fixed landing gear and composite construction. The engine was a Continental IO-550-N, six-cylinder, fuel-injected, rated at 310 horsepower. The registered owner was SR20 Holdings LTD. The pilot, aged 53, held a U.S. Airline Transport Pilot License (issued August 2006) with multi-engine land privileges, and a Commercial Pilot Certificate with single-engine land, sea, and glider ratings. He had a first-class medical certificate with the restriction "Must wear corrective lenses."
Investigation Findings
The Air Accident Investigation Department (AAID) investigated. The engine was removed and disassembled under AAID supervision with representatives from Cirrus Aircraft and Continental Motors. No impact damage was found to the engine. Data from the last flight indicated that oil pressure dropped to 1 psi, then rose to 22 psi during full power, but fell to less than 5 psi within 27 seconds. About two minutes and six seconds after full power, the exhaust gas temperature for cylinder #5 dropped significantly, followed by cylinder #1 12 seconds later; engine RPM also decreased. Oil temperature rose to a maximum of approximately 198.5 °F after full power and did not decrease until 33 seconds before the end of the recording. Examination revealed that the #3, #4, #5, and #6 connecting rods, bearings, and journals showed lubrication distress and damage. The #5 connecting rod had separated from the crankshaft, and the #5 piston was destroyed. The #3 main journal exhibited lubrication distress, and the #2, #3, and #4 main bearings showed damage consistent with lubrication distress. All engine accessory components were intact and unrelated to the probable cause. Weather was not considered a factor.
Probable Cause
The AAID determined the probable cause to be an engine malfunction related to the lack of oil pressure to the bearings of the connecting rods and the crankshaft journals, thus increasing operating temperatures. The initial causal factor of the oil starvation was not determined.