Flight Crew Commercial
Aircraft Equipment Problem Less Severe
Flight Crew Diverted; Flight Crew Overcame Equipment Problem; Flight Crew Landed As Precaution
Aircraft
On departure climbing through about 5000 ft. we had a power reduction of roughly 10 inches on the TRQ and corresponding drop of the NG to around 88-90%. The reduction of the power wasn't immediate; it took around 20 seconds for the full power reduction. We had noticed the day before at one point on a departure that the power was around 20 inches; which we thought was possibly an accidental reduction of the PCL (Power Control Lever) but didn't remember moving the PCL. When the event happened we made sure to mark the position of the PCL and verify that it wasn't moving with the power reduction. After the reduction of the power we moved the PCL forward and the power was restored to a normal level but we decided it was no longer safe to continue the flight and requested a diversion to ZZZ. We advised Departure that we were having abnormal engine indications and they gave us priority to ZZZ.After talking with Maintenance; it felt like the issue was probably either a loose linkage to the PCL or an issue with the FCU (Flight Control Unit); possibly an air leak.
PC-12 Captain reported an uncommanded power reduction during climb and subsequently diverted.