Narrative:

While enroute during a night cross country training flight; the power plant of the aircraft started sharing very rough and engine would provide only partial power. Immediately I started troubleshooting with the checklist to identify the possible cause. Only a reduction in power below 1500 RPM by the use of the throttle lever would minimize the vibration. I informed approach of the situation; the nearest airport they mentioned was about 9 miles to the east. This power setting did not allow me to maintain altitude at the best glide speed of the aircraft; aircraft kept descending about 200 feet per minute. I directed the aircraft towards the road since it seemed it was the safest place to land. I followed the procedures on checklist for forced landing with engine power. Aircraft landed safe on the road. There was no property damage and no one was harmed. The aircraft was evacuated after it came to a complete stop; and after a few minutes the aircraft was pushed to the grassy area besides the road to prevent the aircraft from being damaged by local automobile traffic in the dark road. After emergency personnel left the area; I remained near the aircraft until mechanics and flight school representative arrived at the scene. Mechanics inspected the aircraft and mentioned that cylinder #2 was damaged and that the most likely cause was improper valve seating adjustment during maintenance. The aircraft had recently been released of 100 hour inspection according to maintenance logbooks. I aided in the removal of the wings and the aircraft was towed back to the airport.

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Original NASA ASRS Text

Title: A C152 pilot reported the loss of engine power that resulted in an off-field landing.

Narrative: While enroute during a night cross country training flight; the power plant of the aircraft started sharing very rough and engine would provide only partial power. Immediately I started troubleshooting with the checklist to identify the possible cause. Only a reduction in power below 1500 RPM by the use of the throttle lever would minimize the vibration. I informed Approach of the situation; the nearest airport they mentioned was about 9 miles to the east. This power setting did not allow me to maintain altitude at the best glide speed of the aircraft; aircraft kept descending about 200 feet per minute. I directed the aircraft towards the road since it seemed it was the safest place to land. I followed the procedures on checklist for forced landing with engine power. Aircraft landed safe on the road. There was no property damage and no one was harmed. The aircraft was evacuated after it came to a complete stop; and after a few minutes the aircraft was pushed to the grassy area besides the road to prevent the aircraft from being damaged by local automobile traffic in the dark road. After emergency personnel left the area; I remained near the aircraft until mechanics and flight school representative arrived at the scene. Mechanics inspected the aircraft and mentioned that cylinder #2 was damaged and that the most likely cause was improper valve seating adjustment during maintenance. The aircraft had recently been released of 100 hour inspection according to maintenance logbooks. I aided in the removal of the wings and the aircraft was towed back to the airport.

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.