On September 10, 2005, about 1610 eastern daylight time, an amateur built Arnet Pereyra Aero Design, Aventura II, N9138W was substantially damaged during approach to Hobbs Pond near Hope, Maine. The non-certificated pilot/owner was seriously injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight, conducted under 14 CFR Part 91. According to the pilot, the aircraft was leveling off at an altitude about 300 feet above ground level, after completing a left downwind to base traffic pattern leg. The airplane's airspeed was at 65 knots, and it was configured in the 10-degree landing flap position, when an approximate 15 knot gust of wind, "took the airplane into a stall." The airplane entered a spin, and during the recovery by the pilot, impacted water resulting in substantial damage. The recorded weather at BGR, about 23 nautical miles north of the accident site at 1553, included: winds from 350 degrees at 12 knots, gusting to 15 knots.