On May 26, 2024, at 1200 eastern daylight time, a Great Lakes 2T-1 (Menasco Special), N818K, was substantially damaged when it was involved in an accident near Salisbury, Maryland. The pilot and pilot-rated passenger were seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The airplane was an open-cockpit, 2-place, tandem-seat vintage biplane equipped with a 125 -horsepower reciprocating engine. The pilot had a total of 14,135 hours of flight experience, of which 30 hours were in the accident airplane make and model. The pilot flew the airplane from the rear seat and the pilot-rated passenger was in the front seat. The airplane departed from Bennett Airport (1N5), Salisbury, Maryland, just before 1200. According to the pilot-rated passenger, this was the second flight of the day for the pilot and airplane. The pilot had completed a flight previously with another passenger that was uneventful. The passenger stated that she remembered taxiing out to runway 35 for departure, and normal engine operation to that point. She stated that during the flight the airplane felt “slow and mushy,” but thought that this feeling may have been because she was unfamiliar with the airplane. She stated that she was not flying the airplane when the accident occurred and could not recall any other details from the accident flight. The passenger from the previous flight watched the airplane depart on runway 35 for the accident flight and make a right turn. Shortly after the right turn, he watched the airplane make a 180° turn back toward the airport. The airplane was descending and went behind trees where he lost sight of it. He then reported hearing a “thud” and saw a puff of dust in the distance. He could not remember hearing the engine due to his distance from the accident site. The witness also recorded a video of the takeoff that concluded shortly after the airplane’s initial turn to the right. Strong engine noise could be heard for the duration of the video. The pilot stated that he could not remember the accident, but did recall some of the details from earlier that day. Before the first flight of the day, the pilot and both passengers completed a preflight inspection of the airplane that included adding 5 gallons of fuel to the single fuel tank. The pilot recalled that the airplane was holding about 20 gallons total of 100LL fuel and that he had filled the fuel tank from a gasoline canister that he kept in his hangar. The pilot also commented that the airplane had three gallons of oil in it. The pilot was asked if the passenger flew the airplane on the first flight of the day and the pilot stated that they may have but he was unsure. The pilot was unable to recall if the passenger on the accident flight was intending to fly the airplane. The airplane came to rest in a grassy open field about ½-mile northeast of 1N5, and the wreckage displayed damage signatures that were consistent with a left wing- and nose-low attitude at impact. The empennage was mostly undamaged. Postaccident examination of the airplane confirmed control cable continuity from the flight controls in the cockpit to each flight control surface. Examination of the engine did not reveal evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation.