Dash 8-200
Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Critical
Flight Crew Inflight Shutdown; Flight Crew Landed in Emergency Condition
Aircraft
In cruise flight the Number 1 Prop RPM went from 900 to 1070 the torque also went up; I reduced the torque to match the Number 2 Engine. All other indications were normal so I increased the Number 2 Prop RPM to sync it with the Number 1 Engine. As we got closer to destination I reduced the power levers to flight idle to see what would happen. The Number 1 Engine would not go below 45% torque; landing in this configuration did not sound like a good plan; so we elected to shut down the Number 1 Engine. We contacted Dispatch to inform them of the situation and we then ran the Engine Shutdown Checklist. The prop would not feather with the condition lever but did feather with the alternate feather switch selected. The engine was still running at 45% so not knowing the cause of these issues we elected to shut the engine down with the T handle.
DHC8-200 Captain reports Number One Propeller RPM increasing from 900 to 1070 on its own in cruise flight. The torque also increases. When the Number One Engine power lever is reduced to idle the engine will not go below 45% and it is decided the engine will need to be shut down. The prop would not feather with the condition lever but did feather with the alternate feather switch.