Narrative:

We had just received this aircraft the day before and it was 24 years newer than what we had been flying. The chief pilot called and ask if I could fly to an outlying field and pick up a medical team and fly them back to home base. I took my time and ran the complete checklist and departed on the active runway.the aircraft accelerated normally and after I rotated I took my hands off the throttles to raise the landing gear; the left engine lost power. Auto feather was engaged so the aircraft was kept in control and I notified the tower I had an engine failure and continued to climb to a safe altitude. They asked me if I needed priority and said negative and requested for a few minutes to sort the problem out. I started to troubleshoot and found the left power lever was at idle. Advancing the power lever restored normal power and I continued without incident.

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Original NASA ASRS Text

Title: BE90 First Officer reported a loss of power after takeoff on one engine due to the friction lock not being set for a throttle.

Narrative: We had just received this aircraft the day before and it was 24 years newer than what we had been flying. The chief pilot called and ask if I could fly to an outlying field and pick up a medical team and fly them back to home base. I took my time and ran the complete checklist and departed on the active runway.The aircraft accelerated normally and after I rotated I took my hands off the throttles to raise the landing gear; the left engine lost power. Auto feather was engaged so the aircraft was kept in control and I notified the tower I had an engine failure and continued to climb to a safe altitude. They asked me if I needed priority and said negative and requested for a few minutes to sort the problem out. I started to troubleshoot and found the left power lever was at idle. Advancing the power lever restored normal power and I continued without incident.

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.