Narrative:

The autopilot was inadvertently turned on. This plane has no indicator that the autopilot is on. Traveling the distance to ZZZ; the plane was not easily responding to the stick inputs. All inputs were accepted but very difficult to push. In addition; within 15 NM from ZZZ the engine emergency light came on 3 times; with the engine RPM suddenly drastically reducing. Upon returning to ZZZ; it was found that 1 wing tank was empty; when leaving the airport the dipstick showed 7 gallons. The other had 4 gallons remaining. The total flight time was 1.4 hours. Landing was difficult but uneventful. Flight instructors discovered the problem.

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Original NASA ASRS Text

Title: A Flight Design CTRS does not display the status of the autopilot engagement and when the autopilot is engaged the aircraft is difficult to control. When landing the engine emergency light illuminated with reduced rpm and one wing tank was found empty.

Narrative: The autopilot was inadvertently turned on. This plane has no indicator that the autopilot is on. Traveling the distance to ZZZ; the plane was not easily responding to the stick inputs. All inputs were accepted but very difficult to push. In addition; within 15 NM from ZZZ the engine emergency light came on 3 times; with the engine RPM suddenly drastically reducing. Upon returning to ZZZ; it was found that 1 wing tank was empty; when leaving the airport the dipstick showed 7 gallons. The other had 4 gallons remaining. The total flight time was 1.4 hours. Landing was difficult but uneventful. Flight instructors discovered the problem.

Data retrieved from NASA's ASRS site as of April 2012 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.