Narrative:

Engine partial failure on climbout after departing. VFR at 1200 MSL. First flight for the airplane (C150) after coming out of annual inspection. I stated I was returning to the field. I was cleared to land on runway 2 or 20. No traffic conflicts. Normal landing. I taxied to the maintenance hangar. Mechanic heard the noise the airplane was making as I taxied. He thought I had a stuck valve.I was at 500 feet AGL and 2 miles from the airport (departure end). I knew I had sufficient altitude to make a 180 and return to field. I was also aware that no other aircraft were being handled by ATC at the time.

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Original NASA ASRS Text

Title: C150 pilot climbing through 1;200 feet returned to the departure airport after a partial power failure. The flight was its first following an annual inspection.

Narrative: Engine partial failure on climbout after departing. VFR at 1200 MSL. First flight for the airplane (C150) after coming out of annual inspection. I stated I was returning to the field. I was cleared to land on Runway 2 or 20. No traffic conflicts. Normal landing. I taxied to the maintenance hangar. Mechanic heard the noise the airplane was making as I taxied. He thought I had a stuck valve.I was at 500 feet AGL and 2 miles from the airport (departure end). I knew I had sufficient altitude to make a 180 and return to field. I was also aware that no other aircraft were being handled by ATC at the time.

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.