On October 29, 2016, about 1600 eastern daylight time, an experimental, amateur-built Pitts Special S-1, N27832, was substantially damaged when it impacted a river, following a loss of control during aerobatic flight near Coastal Regional Airport (EWN), New Bern, North Carolina. The commercial pilot incurred minor injuries. The airplane was registered to and operated by the commercial pilot as a personal flight conducted under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the local flight that departed EWN about 1545. The pilot reported that he was practicing aerobatics about 3 miles northeast of EWN, over the Neuse River. During the maneuvers, as he input left aileron, the control stick was stiff and he believed he observed abnormal movement of the upper left aileron. He then applied more force to free the control stick and input right aileron; however, the airplane continued to roll left and entered a spin. The pilot was unable to recover from the spin and subsequently parachuted from the airplane. Both the pilot and the airplane came to rest in the Neuse River. Examination of the wreckage by a Federal Aviation Administration (FAA) inspector and the pilot revealed substantial damage to the wings and fuselage. They also noted that a majority of the left wings, including the ailerons and aileron control tubes, were not recovered from the river. As such, control continuity could not be verified. The single-seat, bi-wing, fixed-tailwheel airplane, was assembled from a kit and issued an FAA experimental airworthiness certificate in 1994. Its most recent annual conditional inspection was completed on July 21, 2016. At that time, the airplane had accrued 170 total hours.