Date: 201410
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Weather elements / visibility: Rain; 7
Light: Night
Aircraft: Skyhawk 172/Cutlass 172
Operator: FBO
Operating under: Part 91
Flight plan: IFR
Mission: Ferry / Re-Positioning
Flight phase: Initial Climb
Airspace: Class B ZZZ
ATC / advisory: TRACON ZZZ
Aircraft component: Reciprocating Engine Assembly
Component problem: Failed
Reporter organization: FBO
Reporter function: Pilot Not Flying
Reporter qualification: Flight Crew Flight Instructor; Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Second reporter function: Pilot Flying
Anomaly: Aircraft Equipment Problem Critical
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Returned To Departure Airport; Flight Crew Landed in Emergency Condition; General Declared Emergency
Contributing factors: Human Factors; Aircraft
Primary problem: Ambiguous

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.


Second narrative: Through a timeframe beginning around noon until shortly before the event I personally flew this aircraft on a crew ferry mission. The airplane traveled [on the first leg] with no abnormalities and took on 20 gallons of fuel. After the fuel was checked the aircraft departed on an IFR flight plan to (ZZZ). This leg was also flown with no abnormalities. We purchased 10 gallons of gas from [the ZZZ FBO]; bringing our onboard total to roughly 18 gallons. The fuel was checked and no contamination was noticed. We entered the aircraft for the last leg of the mission; and received clearance for our IFR flight. I was the pilot flying and Mr. X was working navigation and communications. The aircraft performed engine start; taxi; and run-up with no abnormalities. After a brief delay we received clearance for takeoff and began talking with Approach on climb out. We entered into the overcast layer at 1900 FT; and upon reaching roughly 2100 FT-2200 FT the engine sputtered and experienced a loss of power. Having my right hand already on the throttle I ensured that both it and the mixture were full open and rich; respectively. I ensured the fuel selector was set to 'Both' and that the fuel shutoff valve was open. I then activated the electric auxiliary fuel pump. Noticing persisting engine roughness and decreased power; I initiated a descending left turn to both exit the overcast layer and begin heading back. Simultaneously Mr. X declared an emergency and declined vectors to the ILS; as we had cleared the cloud deck. Searching for a suitable runway I flew a descending arc towards the airport; with the aircraft appearing to make less than normal power given the full-open position of the throttle. As we orbited the airfield from the 090 radial north-westward there was minor confusion to our exact location. Upon seeing definitive runway edge lights I chose to land the aircraft on that surface. It was unknown at the time what our selected runway was. The engine ceased to make power on the landing flare and the prop stopped windmilling on the ground roll. The aircraft came to rest just inside the edge of an active runway. We quickly egressed the aircraft and pushed it off the runway and into a taxiway intersection. Seconds later we were met by emergency response personnel.


Synopsis: 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.