Narrative:

This cessna 172S had just flown between seven and eight hours without anomaly. I was the front right passenger. I was handling radios and navigation for the PIC. We landed with approximately 12-15 gallons of fuel. 5 gallons per side was added by the FBO. 100LL was requested. Neither myself nor the PIC watched the fueling of the aircraft. Prior to engine start; the PIC sumped all of the fuel drains and found no contamination. As part of the preflight activity a runup was accomplished nothing no anomaly. We departed [after dark] and while climbing through 2;100 msl or so the engine experienced a severe hesitation. After determining that it was not pilot induced and remedies such as mixture/throttle adjustment would not cure the now rough engine an immediate left turn was made and an emergency was declared. The controller acknowledged and offered a vector to the ILS and I declined; opting for a visual approach now that we had descended below the overcast. The only runway lights that came into view were those of runway xx (closed) on which we landed uneventfully. The engine (prop) stopped turning as we rolled to a stop. At the point we rolled to a stop we both noticed that we had rolled onto an active runway. We immediately exited the aircraft and pushed it off of runway and onto a taxiway where we were met by fire/rescue personnel. Metar 150/7g14 10SM -RA OVC019 A2982.

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Original NASA ASRS Text

Title: Cessna 172 pilot experiences a rough running engine passing 2;000 ft on departure and elects to return. ATC is advised and an emergency is declared. The engine continues to make power until the landing flare; where it quits completely.

Narrative: This Cessna 172S had just flown between seven and eight hours without anomaly. I was the front right passenger. I was handling radios and navigation for the PIC. We landed with approximately 12-15 gallons of fuel. 5 gallons per side was added by the FBO. 100LL was requested. Neither myself nor the PIC watched the fueling of the aircraft. Prior to engine start; the PIC sumped all of the fuel drains and found no contamination. As part of the preflight activity a runup was accomplished nothing no anomaly. We departed [after dark] and while climbing through 2;100 msl or so the engine experienced a severe hesitation. After determining that it was not pilot induced and remedies such as mixture/throttle adjustment would not cure the now rough engine an immediate left turn was made and an emergency was declared. The controller acknowledged and offered a vector to the ILS and I declined; opting for a visual approach now that we had descended below the overcast. The only runway lights that came into view were those of runway XX (closed) on which we landed uneventfully. The engine (prop) stopped turning as we rolled to a stop. At the point we rolled to a stop we both noticed that we had rolled onto an active runway. We immediately exited the aircraft and pushed it off of Runway and onto a taxiway where we were met by fire/rescue personnel. METAR 150/7G14 10SM -RA OVC019 A2982.

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.