ERA09LA310

A loss of engine power for undetermined reasons.

About 7 months before the accident, the carburetor was overhauled, but after installation, the engine could not be restarted when it was hot, and lost power one time in flight. The carburetor was returned to the overhaul facility, repaired, and re-installed a second time. According to the pilot-rated co-owner/passenger, the engine ran "fine" during a test flight, and no flights were conducted between the test flight and the accident flight. Estimates by the pilot and passenger indicated that the accident flight departure fuel quantity was between 26 and 32 gallons. The pilot and passenger departed their home airport for another airport approximately 20 miles away, conducted two touch-and-go landings, and began the return leg to their home airport. While in cruise at 1,100 feet, the engine ran roughly for a brief period of time, and then lost all power. The pilot attempted to restart the engine, but was unsuccessful. The airplane struck trees, and came to rest approximately 25 feet above the ground, suspended by the trees. Based on the pilot's account of the departure fuel quantity and the duration of the flight, the airplane manufacturer's fuel consumption rates did not support the case for fuel exhaustion, but neither the pre-flight nor post- accident fuel quantities were able to be accurately determined. The engine was operated successfully in a post-accident ground test, and subsequent examination and test of the carburetor did not reveal any anomalies. When the intersection of the local temperature and dew point values was located on a chart that depicted carburetor ice envelopes, the point was in the envelope entitled "Serious Icing at Glide Power," near the boundary of the envelope entitled "Icing - Glide and Cruise Power."

HISTORY OF FLIGHT On May 30, 2009, about 1044 eastern daylight time (EDT), a Cessna 172M, N12151, was substantially damaged following a loss of engine power and a subsequent forced landing near Sarasota, Florida. The pilot and the pilot-rated co-owner/passenger received minor injuries. The personal flight was operated under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed for the flight, and no flight plan was filed. According to the pilot, he performed a preflight inspection of the airplane using the airplane's checklist, and nothing unusual was noted. The preflight included a visual inspection of each fuel tank. The pilot stated that the left fuel tank was approximately one-half full, and the right tank was approximately three-quarters full. For the flight, the pilot was seated in the left seat, and the co-owner/passenger was seated in the right seat. The engine started normally, and the engine run-up was normal. The airplane departed Sarasota/Bradenton International Airport (SRQ), Sarasota/Bradenton, Florida about 1000, and flew to Venice Municipal Airport (VNC), Venice, Florida, located about 20 miles south of SRQ. The pilot performed two touch-and-go landings at VNC, and then initiated a return to SRQ. When the airplane was cruising at an altitude of 1,100 feet above mean sea level (msl), and still several miles from SRQ, the engine started to run rough, and then completely lost power. The pilot attempted to restart the engine, but was unsuccessful. At the same time, he turned the airplane towards a beach he had selected for an emergency landing. While still airborne, the airplane struck trees approximately 300 yards prior to the beach, and came to rest approximately 25 feet above the ground, suspended in the trees. The co-owner/passenger provided a similar description of the sequence of events. He stated that the pilot performed the preflight inspection using a checklist, and stated that there were "31 to 32" gallons of fuel onboard at the beginning of the flight. The co-owner/passenger observed that the oil pressure and cylinder head temperature readings were "normal" during the return flight from VNC. He stated that when the airplane was in cruise at an altitude of approximately 1,100 feet, the engine suddenly stopped producing power, but the propeller continued to windmill. Both he and the pilot stated that the fuel selector valve was set to the "BOTH" position for the flight, as well as when the engine stopped developing power. He confirmed that the pilot turned the airplane towards a beach, and that they struck trees prior to reaching it. Both the pilot and the co-owner/passenger were wearing their seat belts and shoulder harnesses. They exited the airplane with the assistance of local fire and rescue personnel. PERSONNEL INFORMATION Federal Aviation Administration (FAA) records indicated that the pilot held a commercial pilot certificate with airplane single-engine land and instrument airplane ratings. He also held a ground instructor certificate with an advanced ground instructor rating. His most recent FAA second-class medical certificate was issued in May 2008, at which time he reported 404 total hours of flight experience. His most recent flight review was accomplished in September 2008. According to the pilot, at the time of the accident, he had 418 total hours of flight experience, including approximately 180 hours in the accident airplane make and model. FAA records indicated that the co-owner/passenger held flight instructor and commercial pilot certificates, with airplane single-engine land, instrument airplane, and glider ratings. He also held a mechanic certificate with airframe and powerplant ratings, and an inspection authorization. His most recent FAA third-class medical certificate was issued in August 2006, at which time he reported 3,500 total hours of flight experience. AIRCRAFT INFORMATION According to FAA records, the airplane was manufactured in 1973, and was first registered to the current owners in 2001. The airplane was equipped with a Lycoming O-320-E2D engine. According to the co-owner/passenger, the engine was last overhauled in September 1990, when it had a total time of approximately 2,000 hours in service. The airplane maintenance records indicated that the most recent annual inspection was completed on July 1, 2008, and a "Total A/C Time" of 3,198.5 hours was indicated in the entry. That entry was signed by the other co-owner of the airplane. Another maintenance records entry dated July 7, 2007, and which appeared to record an annual inspection, also cited a "Total A/C Time" of 3,198.5 hours. That entry was signed by the co-owner/passenger of the airplane. The airplane tachometer registered 3,171.1 hours at the time of the accident. No other hour meter was installed on the airplane. The reason for the discrepancy between the maintenance records entries and the tachometer reading could not be determined. METEOROLOGICAL INFORMATION The 1053 automated weather observation at SRQ, located 6 miles north of the accident site, included winds from 270 degrees at 11 knots, visibility 10 miles, few clouds at 1,500 feet, temperature 28 degrees C, dew point 22 degrees C, and an altimeter setting of 29.94 inches of mercury. The temperature and dew point values indicated a relative humidity of approximately 70 percent. When the intersection of the two temperature values was located on a chart that depicted carburetor ice envelopes, the point was in the envelope entitled "Serious Icing at Glide Power," near the boundary of the envelope entitled "Icing - Glide and Cruise Power." WRECKAGE AND IMPACT INFORMATION According to information provided by local law enforcement and FAA personnel who responded to the accident, the accident site was located approximately 6 miles south of the destination airport. The airplane came to rest slightly nose-down, with a bank attitude of approximately 60 degrees left wing down. The lower and aft fuselage sustained some crushing and tearing damage, but the cockpit/cabin area was predominantly intact. The flaps were found to be deployed to approximately 30 degrees. The empennage sustained significant crush and other deformation damage. Shortly after the accident, fuel was observed to be leaking from the tank vent tube in the left wing, but the fuel was not captured, and no estimates of the quantity were obtained. The airplane was recovered from the tree, and transported to a secure storage facility for additional examination. According to a representative of the insurance company that insured the airplane, an environmental services company, in conjunction with Sarasota County environmental officials, conducted a limited site evaluation on June 11, which was 13 days after the accident. Soil samples were collected from several locations at the accident site. Samples were screened using a direct-reading instrument, and results of the soil screening found "no evidence of petroleum hydrocarbon impacts at the site." ADDITIONAL INFORMATION Airplane Fuel Quantity Information FAA Type Certificate Data Sheet (TCDS) 3A12 stated that the accident airplane was equipped with two 21-gallon fuel tanks, for a total fuel capacity of 42 gallons. The TCDS stated that the usable fuel quantity was 38 gallons for "all flight attitudes" when the fuel selector valve was set to the "BOTH" position, and 19 gallons "in level flight" in either tank, when the fuel selector valve was set to that tank. According to the airplane manufacturer's Owner's Manual (OM), the airplane was equipped with two 21 gallon fuel tanks, one in each wing. A decal near each tank filler neck stated "19 GAL CAPACITY." The OM performance charts indicated that gross weight fuel consumption values at an altitude of 2,500 feet ranged between 6.3 gallons per hour (gph) and 9.7 gph, depending on the engine power setting. Review