On April 9, 2009, approximately 1615 central daylight time, a Cessna 182T, N1491D, was substantially damaged upon collision with terrain following a loss of control during initial takeoff from a private airfield near Stigler, Oklahoma. The private pilot was seriously injured and the two passengers received minor injuries. Visual meteorological conditions prevailed and an instrument flight rules (IFR) flight plan was filed for the Title 14 Code of Federal Regulations Part 91 personal flight. The airplane was owned and operated by a private individual. The 108 nautical mile cross-country flight was originating at the time of the accident and was destined for the Ardmore Municipal Airport (ADM), Ardmore, Oklahoma. An initial statement from the passenger, collected by a Federal Aviation Administration (FAA) inspector, stated that during takeoff, the airplane encountered a gust of wind. The pilot lost control of the airplane, collided with terrain and nosed over, coming to rest in the inverted position. In a telephone interview with the pilot, he could not recall the accident sequence. He stated that he normally would set 20 degrees of flaps and take off to the north. He recalled obtaining a weather briefing, but could not remember any specific details. An on-scene examination of the airframe was conducted by representatives from the National Transportation Safety Board (NTSB), FAA, AmSafe, and the Cessna Aircraft Company. The pilot had attempted to takeoff to the north on the grass strip which had an unmeasured down slope. The ground 219 feet west of the strip displayed ground scars consistent with the airplane's landing gear aligned on a heading of 315 degrees. Approximately 660 feet west of the landing gear ground scars was additional evidence of the airplane contacting the ground aligned on a heading of 300 degrees. Three ground scars consistent with propeller strikes were found not aligned with the larger ground scar, consistent with the airplane being in a "crab" during the ground contact. The airplane came to rest in the inverted position. The outboard four feet of the left wing displayed signs of rearward crushing, and this section was found folded on top of the wing. Control continuity was established from the flight controls to the control surfaces. The flaps were found at 40 degrees. Damage between the left flap and left aileron was consistent with 40 degrees of flap at the time of damage to the left wing. The propeller remained attached to the engine. All blades displayed chord-wise scratches and leading edge polishing consistent with engine power at the time of impact. The examination of the airframe and engine failed to reveal any pre-impact anomaly. The airplane was configured with four AmSafe airbag systems. None of the AmSafe airbag systems deployed during the accident sequence. An on-scene examination of the AmSafe system did not reveal any anomaly in the systems and the system's Electronics Module Assemblies (EMA) were removed from the accident airplane and tested at AmSafe's facility in Phoenix, Arizona. The crash sensors and firing signals performed within the approved tolerances. A review of the pilot's operating handbook (POH) revealed that "flap deflections of 30 degree to 40 degree are not recommended at any time for take-off." Furthermore, "take-offs into strong crosswinds normally are performed with the minimum flap setting necessary for the field length, to minimize the drift angle immediately after take-off. The airplane is accelerated to a speed slightly higher than normal, then pulled off abruptly to prevent possible settling back to the runway while drifting. When clear of the ground, make a coordinated turn into the wind to correct for drift." At 1610, an automated weather reporting facility at Sallisaw Municipal Airport (JSV), located about 20 nautical miles northeast of the accident site reported winds from 170 degrees at 16 gusting to 21 knots. At 1653, an automated weather reporting facility at Davis Field Airport (MKO), located about 29 nautical miles northwest of the accident site reported winds from 160 degrees at 21 knots gusting to 29 knots with a remark that at 1620 a peak wind gust from 150 degrees at 35 knots was recorded.