On May 18, 2025, about 1416 eastern daylight time, an experimental, amateur-built Zenith 750, N864AJ, was substantially damaged when it was involved in an accident near Greenville, South Carolina. The private pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot stated that the airplane’s condition inspection had just been completed. He subsequently removed the engine cowling and performed two separate 5-minute engine runs, and a third engine run that was 7 minutes in duration. After each engine run, the pilot secured the engine and then checked from the firewall forward to confirm that there was no engine oil leakage. He then performed a complete preflight inspection of the airplane noting the oil capacity was 3.5 quarts (normal). After departure, the pilot proceeded in a westerly direction and during cruise flight at 2,200 ft mean sea level (1,200 ft above ground level) with the engine operating about 2,400 rpm, he heard an aural annunciation of “oil pressure” twice from the on-board avionics. The pilot increased engine speed about 100 rpm and noted that the oil pressure reading on the multi-function display was 28 psi. The engine was developing partial power, and the pilot pitched the airplane for best glide airspeed; however, he was too far to reach his intended airport. The pilot maneuvered toward a forced landing area in a residential development; however, on final approach he realized the terrain was not smooth. When he flared for landing, the main landing gear impacted the top of a very steep incline and separated. The airplane then rolled between 10 and 15 ft and nosed over. The airplane was recovered for further examination.