Skyhawk 172/Cutlass 172
Flight Crew Private
Flight Crew Last 90 Days 23; Flight Crew Total 170; Flight Crew Type 120
Aircraft Equipment Problem Critical
Air Traffic Control Provided Assistance; Flight Crew Landed in Emergency Condition; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Overcame Equipment Problem; General Maintenance Action
Aircraft
I did a touch and go on Runway X at ZZZ. After takeoff; I began flying a standard pattern. Once I started my turn to downwind from crosswind; I heard a very loud bang; the engine had faulted. The bang that came from the engine startled me so I trimmed for glide speed (65 kts.) and continued my turn back towards the runway. I then [advised ATC] to report them on the situation and told them repeatedly that I was landing Runway X. I then rolled out onto a left base for Runway X. Tower cleared me to land. After landing; I taxied the airplane clear of the runway and shut it down. A sparkplug blew out of one of the cylinders causing me to lose engine power. The aircraft was returned to its previous airworthy state after the aircraft was inspected and the sparkplug was replaced by a certified mechanic. It was returned to its operating state one day after the situation after the mechanic signed off on the aircraft. A test flight was also successfully completed by request of the mechanic before its return to service.
C172 Pilot reported an engine malfunction shortly after takeoff that resulted in a return to the departure airport.