CHI06FA109

The pilot's inadequate preflight inspection of the helicopter that failed to discover water in the fuel, resulting in a loss of engine power while maneuvering, and an in-flight collision with trees and terrain. Factors associated with the accident were inadequate fuel storage, and the low altitude of the helicopter.

A private pilot was operating the helicopter as a local personal flight when it collided with trees and terrain during a forced landing. Witnesses related that the helicopter appeared to lose power, as if it ran out of gas, and that it came down fast, toward a road. The helicopter subsequently struck trees and terrain. An on-scene inspection disclosed no evidence of any preimpact mechanical anomalies with either the flight controls or engine. Fuel samples were collected from the helicopter's carburetor and fuel tanks. Analysis disclosed water in the carburetor fuel, but none in the fuel tanks. A fuel sample was also taken from the pilot's storage tank at his residence, which was under a building without rain gutters. The fuel from the storage tank had a layer of water and sediment. Detailed analysis of the water and sediment found in the carburetor fuel indicated that the contamination was consistent with run-off from a building's roof. The helicopter's engine was provided fresh fuel and operated successfully. During the investigation, an aviation mechanic related that about two weeks before the accident, the pilot had lost one of the helicopter's fuel caps, and had obtained a replacement cap.

HISTORY OF FLIGHT On April 13, 2006, about 1530 eastern daylight time, a Robinson R22 Beta helicopter, N887BC, piloted by a private pilot, sustained substantial damage on impact with trees and terrain during a forced landing following an in-flight loss of engine power while maneuvering near Chelsea, Michigan. The personal flight was operating under 14 CFR Part 91. Visual meteorological conditions prevailed at the time of the accident. No flight plan was on file. The pilot and passenger sustained fatal injuries. The local flight originated from a private landing area near Chelsea, Michigan, about 1515. The pilot was a Fire Captain and operated the helicopter. The passenger was the Chief of Police for Chelsea, Michigan. The flight was in support of a search for a suspect near Chelsea. A Washtenaw County Sheriff's deputy was on the road that the accident occurred on and witnessed the accident. His report, in part, stated: I heard radio traffic that Chelsea K9 was at the scene and a helicopter was requested to assist. I saw a helicopter flying from the West. The helicopter went east from my location around the woods. I next saw the helicopter coming from the East in front of my location. The helicopter turned from the East to the South at the end of Staebler Rd. As the helicopter turned it was heading towards me. The helicopter was coming down in my direction. The helicopter waved back and forth and then turned to the East. I saw the helicopter crash into the trees and hit the ground. ... I did observe the rotor blades spinning. I noticed the weather was warm with light clouds, but overcast. The wind was light but I don't have a wind direction. The Sheriff's office interviewed witnesses in the area. The interview of the witnesses, in part, stated: [The witnesses] advised me that they were walking in the [field] w/o [west of] Staebler Rd as they were watching the helicopter. They state as the helicopter was approx: 100 yards w/o Staebler Rd, it appears it lost power, as though it had run out of gas. [The witnesses] stated it appeared as though the pilot was attempting to land the helicopter on Staebler Rd, but it came down fast. At that point they lost sight of the helicopter. PERSONNEL INFORMATION The pilot held a private pilot certificate with a single-engine airplane land and helicopter ratings. He held a Federal Aviation Administration (FAA) third-class medical certificate issued on June 3, 2005, with no limitations. He reported that he had accumulated 500 hours total flight time on the application for that medical certificate. On an application for insurance on the accident aircraft dated July 27, 2005, he indicated that he had accumulated 350 hours total flight time, 152 hours in make and model, 250 hours total rotorcraft time, and 150 hours in the past year. A receipt for training indicated that he completed a flight review on August 11, 2005. AIRCRAFT INFORMATION N887BC, serial number 3331, was a Robinson R22 Beta, two-place, two-bladed, single main rotor, single-engine helicopter, with a spring and yield skid type landing gear. The primary structure of its fuselage was welded steel tubing and riveted aluminum sheet. The tailcone was a monocoque structure consisting of an aluminum skin. A Lycoming O-360-J2A, serial number L-38543-36A, engine rated at 145 horsepower, powered the helicopter. The pilot's operating handbook for the helicopter, in part, stated: The fuel system is gravity-flow (no fuel pumps) and includes a vented 20 gallon tank, a shut-off valve in the cabin behind the left seat and a fuel strainer. The air vent is located inside the mast fairing above the fuel tank. A tank drain is located at the forward left side of the tank and is actuated by pushing in on the extended tube. A drain is also provided on the fuel strainer located on the lower left side of the firewall forward of the engine. Both drains should be opened daily prior to the first flight to check for water, sediment and fuel type/grade. The fuel gage located on the panel is electrically operated by a float-type transmitter in the tank. When the gage reads E the tank is empty except for a very small quantity of unusable fuel. The low-fuel warning light on the panel is actuated by a separate electric sender located on the bottom of the tank. When the light goes on, approximately one gallon of fuel is remaining in the tank. The optional auxiliary tank is interconnected with the main tank so one valve controls the flow from both tanks. The aux tank has a separate vent, fuel quantity indicator, and sump drain. The helicopter had its annual inspection completed on August 16, 2005. Entries for that inspection showed that the helicopter had accumulated 642.9 hours of total time. The helicopter's mechanic reported that about ten days to two weeks prior to the accident, the pilot said he had lost a fuel tank cap and requested a new cap. The mechanic had a serviceable used cap for the pilot. METEOROLOGICAL INFORMATION At 1453, the recorded weather at Ann Arbor Municipal Airport, near Ann Arbor, Michigan, was: Wind 270 degrees at 14 knots; visibility 10 statute miles; sky condition scattered 8,000 feet above ground level; temperature 23 degrees C; dew point 7 degrees C; altimeter 30.02 inches of mercury. WRECKAGE AND IMPACT INFORMATION The helicopter came to rest upright along a tree line on the east side of Staebler Road about a half mile north of the intersection of Staebler Road and Jackson Road. Broken branches were observed on trees located next to the wreckage. A depression in the terrain was observed about four feet aft of the helicopter's engine. The helicopter's heading was about 135 degrees magnetic. The depression was inline with the helicopter's heading. The landing gear yielded outward. The cabin area and both windshields exhibited crushing. The cabin seats exhibited crushing down to the level of items stored below the seats. The tailcone was bent to the right side of the helicopter as viewed from the aft facing forward. The location of the bend was about the splice joint forward of the strobe light. The main rotor blades remained attached to the hub. The blades were deformed downward and forward in the direction of rotation. One tail rotor blade had its outer section torn outboard of its root fitting. The root fitting and the other tail rotor blade assembly remained attached to the tail rotor hub assembly. Liquid was found in the auxiliary fuel tank. Both fuel tanks' caps were in place and the caps were of different colors. An on-scene investigation was conducted. The flight controls were traced from the cabin to each flight control surface. All breaks in the controls were consistent with overload. No pre-impact anomalies in the flight controls were observed and control continuity was established. The gascolator was found with its cover dislodged. The gascolator's screen was not recovered. The fuel tank's vents were tested with air pressure and no obstructions were observed. The fuel line elbow at the carburetor was fractured. Engine control continuity was traced from the cabin area to the engine. Engine control continuity was established. Liquid was found in the carburetor and was collected in a container. Liquid from the fuel tank was collected in a container. The engine was able to be rotated by hand and a thumb compression was found at each cylinder. MEDICAL AND PATHOLOGICAL INFORMATION The Washtenaw County Medical Examiner's Office arranged for an autopsy to be performed on the pilot. The FAA Civil Aeromedical Institute prepared a Final Forensic Toxicology Accident Report. The report was negative for the tests performed. TESTS AND RESEARCH The fuel samples collected from the carburetor and the helicopter's fuel