Narrative:

Beginning the day shift; I was briefed to take the aircraft [to a maintenance base] for scheduled maintenance on the aircraft. After performing a walk-around on the aircraft [I] secured myself into the pilot seat. The base mechanic had called me and informed me that snow was in the vicinity of the airport. At that time I noticed snowflakes in the street lights in front of the aircraft. It was deemed not a good idea to go to the airport and the decision was made to wait on the weather to get better before maintenance was performed. While the weather was below minimums the base mechanic had started his daily airworthiness checks and found that the main rotor would not rotate clockwise (agusta 119 main rotor rotates counter-clockwise). After confirming this with me; the mechanic inspected the power turbine section in the engine and saw that it was not turning. Further inspection found snow and ice inside the power turbine section of the engine. Suspect residual water left in the power turbine section froze overnight. Perform aircraft wash/cleaning in temps above freezing. After aircraft washes; start the aircraft to dry out any water that enters the engine. Hangar the aircraft when temps are below freezing. Use engine plugs and covers during washes and inclement weather.

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Original NASA ASRS Text

Title: A119 Pilot reported his mechanic discovered during inspection on the ground that the power turbine section of the engine would not turn because of snow and ice contamination.

Narrative: Beginning the day shift; I was briefed to take the aircraft [to a maintenance base] for scheduled maintenance on the aircraft. After performing a walk-around on the aircraft [I] secured myself into the pilot seat. The base mechanic had called me and informed me that snow was in the vicinity of the airport. At that time I noticed snowflakes in the street lights in front of the aircraft. It was deemed not a good idea to go to the airport and the decision was made to wait on the weather to get better before maintenance was performed. While the weather was below minimums the base mechanic had started his daily airworthiness checks and found that the main rotor would not rotate clockwise (Agusta 119 main rotor rotates counter-clockwise). After confirming this with me; the mechanic inspected the power turbine section in the engine and saw that it was not turning. Further inspection found snow and ice inside the power turbine section of the engine. Suspect residual water left in the power turbine section froze overnight. Perform aircraft wash/cleaning in temps above freezing. After aircraft washes; start the aircraft to dry out any water that enters the engine. Hangar the aircraft when temps are below freezing. Use engine plugs and covers during washes and inclement weather.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.