ERA26LA305

On August 14, 2026, about 1040 eastern daylight time, an experimental amateur-built Zenith Cruzer, N673BK, was substantially damaged when it was involved in an accident near Chatham, Massachusetts. The pilot and the pilot-rated passenger received minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 flight test. According to the pilot and the owner/builder of the airplane, the accident flight was the airplane’s fourth during its phase one testing. The previous three flights were uneventful except for oil temperature anomalies. The owner/builder had adjusted the oil cooler position and the purpose of the accident flight was to verify whether repositioning the oil cooler improved the engine oil temperature readings. The pilot stated that the accident flight was delayed a short time until wind conditions improved. After observing other aircraft operating in the airport traffic pattern, the pilot and the owner/builder decided to proceed with the flight. The preflight inspection, engine runup, and flight control checks were normal. Shortly after takeoff, the pilot reported that the left wing dipped, followed by the right wing, and that the airplane subsequently rocked laterally from side to side. The pilot announced to the owner/builder there was a problem and decided to land the airplane on the remaining runway. Video surveillance footage from the airport showed that the airplane impacted the runway in a left wing down attitude, after which the main landing gear collapsed and the nosewheel separated from the fuselage. The wreckage was retained for further examination.