Incident Overview
On July 12, 2018, a Robinson R-66 helicopter was involved in an incident during engine start at Poznań-Ławica Airport (EPPO), Poland. The pilot had flown the helicopter from its home base at Kobylnica (EPPK) to Ławica for refueling. After refueling, the pilot obtained clearance for departure and proceeded to start the engine.
Sequence of Events
During the engine start procedure, the measured gas temperature (MGT) exceeded 920 degrees Celsius. The pilot aborted the start, and the Engine Monitor Unit (EMU) recorded an error. The incident was reported to the Continuing Airworthiness Management Organization (CAMO). Examination of the EMU data revealed a transient MGT peak of 934 degrees Celsius.
Investigation and Outcome
The helicopter was grounded, and the engine was removed and sent to an authorized maintenance facility for inspection. After inspection, the engine was reinstalled on the helicopter. Following a ground run, the helicopter was returned to service.
Probable Cause
The probable cause of the incident was determined to be an MGT exceeding 150 degrees Celsius during engine start, combined with an insufficient interval between engine shutdown and subsequent restart.
Safety Recommendations
No safety recommendations were issued by the Polish State Commission for Aircraft Accident Investigation (PKBWL).