On August 1, 2009, about 1857 central daylight time, an experimental amateur-built Stirling Starduster biplane, N1XY, sustained substantial damage when it impacted a field following low level maneuvers near Earlham, Iowa. Visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 flight was not operating on a flight plan. The private pilot received serious injuries. The local personal flight originated at time unknown. According to a Dallas County Sheriff’s incident report, a witness observed the airplane perform a roll and then attempted to perform a loop. The report indicated that as “the plane was coming out of the loop, it did not have enough altitude and that is when it struck the ground.” The pilot held a private pilot certificate. His last application for a medical certificate was on October 31, 2005, and on that application he indicated that he had accumulated 900 hours of total flight time. N1XY was an experimental amateur-built Stirling Starduster single-engine, propeller-driven, fixed tailwheel, two-seat, biplane. According to registration and airworthiness records, the biplane was powered by a 180-horsepower Lycoming O-360-A4A engine, serial number L-26691-36A and it drove a Sensenich 78 EM8 fixed pitch propeller. Examination of the wreckage by a Federal Aviation Administration inspector revealed no mechanical anomalies. The pilot was sent an accident report form and a completed one has not been received by the NTSB.