Dash 8-200
Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Critical
Flight Crew Returned To Departure Airport; General Declared Emergency
Aircraft
[We had a] normal pre-flight; engine start; push-back; taxi out; takeoff; and departure. The problem first came apparent climbing above 10;000 FT using a climb power of around 95% torque. We all noticed that the #1 Engine was surging and was further confirmed by the #1 Torque Gauge also rising and falling erratically. The #1 Torque Gauge was fluctuating between 95% and 105% with a noticeable surge on the number one engine. I reduced the power on the number one side so that we did not exceed the engine limitations. All three of us monitored the gauges to see if it was a transient problem. The fluctuations continued with a lowered power setting of around 85%.Reaching 12;000 FT we configured the engine in the cruise configuration; props 900 and a setting of around 92%. The torque and engine surge on the #1 Engine continued to fluctuate to a greater degree causing the aircraft to yaw. We contacted Dispatch and Maintenance. Maintenance had us check various settings including switching off the prop sync. The engine surging problem persisted; while the remainder of the engine gauges remained constant. A decision was made to return to [departure airport]. ATC was notified and they assisted with vectors and no emergency was declared. The emergency vehicles were provided as a precaution but were not needed.
DHC-8-200 Captain reported that the #1 Engine was surging in climb above 10;000 FT. Flight returned to departure airport.