On August 9, 2000, approximately 1445 Pacific daylight time, a Cessna 172N, N737CM, registered to Pacific Flyers, Inc., and being flown by a private pilot, was substantially damaged when it rolled off the upwind end of runway 35 and collided with trees following an aborted takeoff at the Siletz Bay State airport, Gleneden Beach, Oregon. The pilot sustained minor injuries. No flight plan had been filed and visual meteorological conditions prevailed. The flight, which was personal was operated under 14CFR91, and was to have been a brief local evaluation of weather conditions before departing for Salem, Oregon. The pilot was interviewed telephonically and subsequently provided a corroborating written statement (NTSB Form 6120.1/2 attached). He reported that he and his family had arrived at the airport in N737CM on the day previous to the accident (08/08/00). The pilot secured the aircraft following arrival with the installation of a gust lock which he described as "...a simple device that fits through the yoke colum[n] and shaft disabling the use of [the] flight controls." The pilot stated that the day of departure he and his family arrived at the airport intending to depart "...but conditions are marginal for VFR flight. We wait 2 hours for conditions to improve. For[e]cast is for 1500 feet broken. Conditions improve only slightly. Weather provides [a] high degree of agitation. By now we are tired of waiting and want to go home. I determine I will go up solo and estimate weather conditions to see if practical to get out." The pilot further stated, "With my mind focusing on weather conditions I depart without doing a complete preflight. The gust lock remains in. At my normal rotation point I cannot pull the aircraft off the ground. I fully expect the aircraft to fly and keep trying to lift off. At about 500 feet or so I realize even if I do get off the ground I would not clear obstacles. Throttle is pulled back, brakes are applied but to[o] little to[o] late. Aircraft is propelled past [the] end point of [the] runway down [a] steep embankment and seriously damaged." The "BEFORE TAKEOFF" checklist for the Cessna 172N states: 3. Flight Controls - FREE and CORRECT. (Refer to ATTACHMENT POH-I) The approach end of runway 17 (north of the upwind end of runway 35 where the aircraft came to rest) slopes down to the north and is populated with small trees and brush.