20090812048179A

On August 12, 2009 at approximately 10:15 (LCL), Mcdonnell Douglas helicopter N527BB experienced a loss of power and was forced to make an emergency landing in Acworth, GA. The helicopter is registered to a 14 CFR part 135 on demand operator. (Rotorworks LLC, hiram, GA) at the time of the accident the aircraft was performing powerline patrol and had a crew of one pilot and one observer. The pilot stated he was hovering at 1400 ft MSL above a power sub station awaiting clearance into mccollum, GA airspace. After hovering for approximately a 15 seconds mccollum tower cleared the aircraft into the requested airspace. The pilot started a decent to the power lines heading sw to mccollum's airfield. Approximately 5-10 seconds later (1100-1200'MSL) the pilot heard a "bang and a braking" noise coming from the engine and simultaneously received eng out audio and caution lights (red and yellow). The pilot lowered the collective and looked for a place to land. He selected an area that had a retention pond and a marsh area. At this point his rotors were bleeding off and his airspeed was between 50-60 knots, he initiated the autorotation and made a mayday call. At approximately 20 feet above the intended landing area he started his deceleration and at approximately 10 feet he pulled the collective pitch and tried to keep the skids level. The aircraft fell approximately 5-8 feet slightly forward and straight down into the marsh area. The terrain slope caused the aircraft to roll on it's right side. Once on the ground the pilot secured the aircraft and detected electrical smoke. He reached down to verify he had rolled to throttle to the off position but realized it was at the idle detent. He rolled it to the off position and cut the battery off. At that time the pilot exited the aircraft and assisted the observer in his evacuation. The pilot suffered minor injuries and the observer sustained serious injuries.