Amateur/Home Built/Experimental
Flight Crew Private
Flight Crew Last 90 Days 22; Flight Crew Total 120; Flight Crew Type 22
Aircraft Equipment Problem Critical
Air Traffic Control Provided Assistance; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Overcame Equipment Problem; Flight Crew Landed in Emergency Condition; Flight Crew Returned To Departure Airport; General Maintenance Action
Aircraft
On my third touch and go of the morning taking off from [Runway] XXR at ZZZ; just after turning crosswind; there was a tremendous bang followed by vibration from the engine. I [advised ATC] and believe I requested landing on XYR. I reduced power to reduce the vibration and left the engine running at approximately 1600 RPM. The Controller wanted me to go to [Runway] XYL but I didn't think I had the power to make it so continued to XYR and completed the landing. I was able to taxi to the hangar and shut down the engine. I inspected the aircraft airframe and found nothing wrong. I removed the cowling and discovered the starter ring gear had separated from its mounting position on the alternator rotor. It was still attached by one bolt; but had destroyed some wiring and ventilation SCAT tubes.
Zenith CH 750 pilot was performing a touch and go when a loud bang and associated airframe shudder caused an immediate return to the airport for a precautionary landing.