Accident Overview
On November 22, 2019, at approximately 1338 central standard time, a Cirrus SR-22, registration N969JM, was substantially damaged during an accident near Tyler, Texas. The pilot and passenger sustained serious injuries. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a personal flight.
Pilot's Account
According to the pilot, about two minutes after leveling off at 3,000 feet above mean sea level (MSL), the engine experienced a severe shake followed by a large vibration. The pilot checked the multifunction display (MFD) engine parameters, which appeared normal. About two minutes later, the indication for the No. 5 cylinder changed from green to red. Manifold pressure indicated 28.5 inches of mercury, approximately two-thirds full power. The pilot reported the issue to air traffic control (ATC) and planned to divert to an alternate airport.
Unable to maintain altitude, the pilot began a descent. The engine then briefly smoothed out, allowing a climb of about 200 feet per minute before shaking resumed. The pilot declared an emergency with ATC and stated his intention to deploy the Cirrus Airframe Parachute System (CAPS) at 1,000 feet MSL. The airplane descended out of clouds at about 1,200 feet MSL, and the pilot spotted a field to his right. He turned toward the field and attempted to use the high boost fuel pump, but power was not restored. He lowered the nose and deployed CAPS between 550 and 650 feet above ground level (AGL).
The airplane impacted the ground under the parachute canopy and came to rest upright. The passenger extricated the unconscious pilot and moved away. The parachute caught wind, dragging the airplane about a quarter mile into a stand of trees. Initial impact caused substantial fuselage damage; subsequent travel and tree impact caused further fuselage damage and substantial damage to both wings.
Post-Accident Examination
Examination of the Continental TSIO-550 series engine revealed that the No. 5 piston head exhibited cleaning and damage consistent with detonation, while the No. 1 cylinder showed signatures of initial detonation phases. The No. 5 and 6 connecting rods displayed movement consistent with bearing liberation. The fuel manifold and injection nozzles flowed within production specifications. Magneto timing measured 27° before top center (BTC) versus the factory specification of 24° BTC. According to the engine manufacturer, this timing, coupled with a rich mixture, could result in detonation.
The pilot described leaning the mixture to the blue line on the MFD. Cirrus states that the Lean Assist blue line does not account for engine timing. The Cirrus Perspective cockpit reference guide explains that selecting the "ASSIST" key highlights the number and places a light blue box around the exhaust gas temperature (EGT) readout of the hottest cylinder. The system detects peak EGTs for each cylinder lean of peak as fuel flow decreases.
Data Analysis
The airplane was equipped with a Heads-Up Technologies recoverable data module (RDM) recording flight, engine, and autopilot parameters at one-second intervals. Data showed that around 1314:45, the No. 5 cylinder head temperature (CHT) began to rise, EGT decreased, and oil pressure dropped. After a brief recovery lasting about two minutes, the No. 5 cylinder failed. Shortly after, the No. 1 cylinder failed.