Incident Overview
On 24 February 2016, a Cirrus SR-22T was on a planned night IFR flight from Lublin Airport (EPLB) to Poznań-Ławica Airport (EPPO). While cruising at flight level 140 (FL140), the pilot observed uneven engine operation. Adjustments to fuel tanks, boost pressure, and mixture did not resolve the issue. Although the pilot sensed no power loss and instruments indicated adequate power, the outside air temperature of -29°C raised suspicion of ice crystal formation in the fuel.
Pilot Actions
The pilot descended to FL100 where the temperature was -12°C, but the irregular engine operation persisted. The pilot informed Warsaw Approach Control and requested coordination for a precautionary landing at Łódź-Lublinek Airport (EPLL). The tower controller asked whether the pilot was declaring an emergency; the pilot responded that at that moment it was not necessary, as the engine was producing sufficient power and the flight was stable. The pilot confirmed the availability of the Cirrus Airplane Parachute System (CAPS), which is usable up to 1200 feet above mean sea level. The aircraft landed without further incident.
Post-Flight Examination
After taxiing to the parking position, an engine run-up test was performed. When the magnetos were switched to the left position, no parameter changes were observed. On the right magneto setting, the engine died and backfired. After a cooling period of several minutes, the engine was restarted and the same result occurred at low RPM. The pre-flight engine test conducted at Lublin had shown no abnormalities.
Cause
The investigation determined the cause of the engine irregularities to be damage to the right magneto.
Preventive Actions
The aircraft operator discussed the case with flight personnel, verified the damaged magneto with a maintenance organization (documented in a note dated 6 April 2016), and evaluated maintenance procedures for magneto overhaul and replacement—no irregularities were found. The maintenance organization also informed the magneto manufacturer and was in ongoing correspondence regarding the incident at the time of the report.