On July 2, 2016, about 1220 eastern daylight time, a Fleet 16B biplane, N666J, owned and operated by Rhinebeck Aerodrome Museum, was substantially damaged during landing at Old Rhinebeck Airport (NY94), Rhinebeck, New York. The commercial pilot and passenger were not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local flight conducted under the provisions of 14 Code of Federal Regulations Part 91. The pilot stated that during takeoff from a turf runway, the left main landing gear collapsed but did not separate from the airplane. The pilot was aware of the damaged landing gear, and circled the airport. During the subsequent landing on the departure runway, the airplane touched down, flipped over, and came to rest to rest inverted, which damaged the right upper wing and vertical stabilizer. The pilot held a commercial pilot certificate with a rating for airplane single engine land, multi engine land, and a flight instructor certificate. The pilot held a first class medical certificate and reported 643 total hours of flying experience. He reported 25 hours of flying time in the accident airplane make and model. Examination of the wreckage by a Federal Aviation Administration inspector revealed that the left main landing gear strut mount nut that secured the landing gear strut was stripped, and the bolt was missing. Damage consistent with wear was observed on the strut base and the housing. There was no inspection required for the gear strut mount for the Fleet 16B, which was manufactured in 1942. The most recent annual was completed about 38 hours before the accident flight.