On August 16, 2002, at 2215 central daylight time, a Schweizer 300C, N269FW, registered to Freedom Flight, LLC, and operated by the pilot, collided with terrain during an emergency landing following a loss of engine power in the vicinity of Haleyville, Alabama. The personal flight was operated under the provisions of Title 14 CFR Part 91 with no flight plan filed. Visual meteorological conditions prevailed at the time of the accident. The commercial pilot received serious injuries, and the helicopter sustained substantial damage. The flight originated from Tuscaloosa, Alabama, at 2130. The pilot initially departed Demopolis, Alabama, at 1730 for a visual flight rules flight to Russellville, Alabama, with a full fuel load of 49 gallons. After 40 minutes of flight, the pilot became aware of thunderstorms along the intended route and elected to land in Tuscaloosa, Alabama. Once the weather cleared, the pilot departed at 2130 and proceeded toward Russellville, Alabama. After 40 minutes in cruise flight at 2,000 feet MSL, the pilot noticed the sound of the engine changed suddenly, and the helicopter began to descend. The engine and rotor tachometer needles fell below normal operating range, and the pilot's attempts to restore power were unsuccessful. The pilot entered an autorotation and sought a suitable landing area. During flare, the pilot was unable to see the terrain in the darkness, and the helicopter hit the ground hard. Examination of the wreckage revealed the skids were spread and broken, the cockpit glass was broken, the main rotor blades were buckled, the fuselage framework near the engine assembly was distorted, the left pilot seat sustained downward compression, and the engine displayed damage to the bottom and rear sections. Fuel was observed leaking near the engine fuel pump. Examination of the engine revealed two lower screws of the No. 3 valve cover were missing. The attachment bolts of the intake pipes of both the No. 1 and No. 3 cylinder assemblies were found loose by three to four revolutions of each bolt. The No. 3 intake pipe was found rotated approximately 180 degrees from the normally installed position. The No. 1 and No. 3 intake pipes were removed for examination, and the gaskets normally installed under the intake pipe flanges were missing. The surfaces of the No. 1 and No. 3 intake pipe flanges and the cylinder intake ports showed signs of metal-to-metal chafing and showed no evidence of gasket material. The attachment bolts of the intake pipes of the No. 2 and No. 4 cylinder assemblies were found secure, and the No. 2 and No. 4 pipe flange gaskets were found installed. The No. 4 intake pipe flange gasket was found split in the inboard area between the attachment bolts. Examination of the bottom spark plugs revealed the No. 1, No. 2, and No. 4 spark plugs were wet with fuel, and the No. 3 spark plug was dry and displayed tan-colored combustion deposits. The engine was rotated utilizing the starter motor, and all four cylinders produced compression and valve action appeared normal. A review of maintenance records revealed the engine received a 100-hour/annual inspection on July 2, 2002, and had operated 38.2 hours since inspection. There was no record of any maintenance performed since the inspection. A review of Title 14 CFR Part 43, Appendix D revealed, (d) "Each person performing an annual or 100-hour inspection shall inspect (where applicable) components of the engine and nacelle group as follows: (2) Studs and nuts - for improper torquing and obvious defects, and (10) All systems - for improper installation, poor general condition, defects, and insecure attachment."