On August 5, 2021, about 2030 eastern daylight time, a Piper J3C-65, N6269H, was substantially damaged when it was involved in an accident near Gosport, Indiana. The pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot stated that, during cruise flight, the airplane experienced “significant” vibration, which was followed by a total loss of engine power. The pilot performed a forced landing to a field that caused the airplane to nose over and impact terrain, resulting in substantial damage to the rudder and cowling. Postaccident examination of the airplane engine revealed that the No. 4 cylinder exhaust valve stem was broken at its base. The valve seat was turned sideways, and pieces of broken metal were found in the cylinder. The cylinder’s rockers and springs did not exhibit any failure.