ERA25LA188

Maintenance personnel had completed an annual inspection of the airplane two days before the accident flight. The pilot reported that during his preflight inspection of the airplane, he observed water contamination when he was sampling fuel from the fuel system, and that he continued to drain fuel samples until he saw no water. The engine start, taxi, run-up and takeoff were uneventful and just after the pilot retracted the landing gear, after which the engine smoothly began losing power, reaching near idle. The pilot decided to land the airplane straight ahead and while gliding he applied full throttle, and the engine briefly revved to about 1,900 rpm before reducing uncommanded again to idle. The airplane subsequently impacted an airport perimeter fence resulting in substantial damage to the horizontal stabilizer. A postaccident examination of the airplane and engine found no evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation. The examination also found that the airplane wing fuel tank caps and filler necks exhibited rust and corrosion, a condition that likely degraded the ability of the seals to keep out water and other contamination. Rust-colored granules and/or corrosion were also observed in the carburetor fuel inlet screen and fitting, gascolator and filter, and the internal check valves of the engine driven fuel pump. This was consistent with long-term water contamination of the fuel system. Liquid recovered from the electric fuel pump and fuel strainer was also contaminated with water, indicating that the pilot’s efforts to eliminate water from the fuel system during his preflight inspection were not successful. Fueling records showed the airplane had last been fueled over a year prior to the accident and airport personnel also reported that the airplane had been stored outside at a tiedown since arriving at the airport 19 years prior to the accident. Data recovered from an engine data monitor revealed that the fuel flow during the accident takeoff roll and initial climb remained relatively constant, and that the exhaust gas temperature readings for all cylinders were erratic. The data monitor did not record engine rpm. The erratic exhaust gas temperature readings with a constant fuel flow indication, and the engine’s partial loss of power during initial climb, were likely the result of water contamination in the fuel system. A review of maintenance logbooks showed that the airplane had no documented service performed for a 14-year period while being stored outdoors on the airport ramp. Maintenance personnel reported that during the most recent annual inspection, the fuel system was visually inspected, the gascolator bowl and filter were removed and cleaned, and the system was not flushed. Based on the available information, it is likely that the airplane’s fuel system was severely contaminated with water that was likely the result of the airplane’s prolonged outdoor storage combinedwith fuel tank cap and filler neck degradation that allowed water intrusion into the fuel tanks. While maintenance personnel reported conducting some inspection of the fuel system during the annual inspection that was completed immediately prior to the accident flight, the pilot’s observation of significant water contamination of the fuel system during his preflight inspection, along with water contamination that was found during the postaccident examination of the airplane indicate that the root cause and the impacts of the water contamination on the fuel system had not been adequately identified or remediated.

On April 23, 2025, at 1703 eastern daylight time, a Cessna 172RG, N6386V, was substantially damaged when it was involved in an accident near Louisburg, North Carolina. The commercial pilot and passenger/owner were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The commercial pilot reported that the purpose of the flight was to take the owner for a post maintenance flight. He performed a preflight inspection of the airplane using the airplane’s pilot operating handbook. During the inspection water was found while sampling the fuel and the commercial pilot continued to drain fuel samples until no water was observed. He then rocked the wings and sampled the fuel again until no water was observed. The engine start, taxi, and run up were completed with no anomalies. During the initial climb, he selected the landing gear to the UP position, after which the engine lost power. He described the loss of power as smooth “like someone had pulled the throttle back to idle.” He selected the landing gear to the down position, reduced the throttle control, and attempted to land on the remaining runway and runoff area. After realizing he could not, he attempted to glide over an airport perimeter fence. During the glide, he applied full throttle, and the engine revved to about 1,900 rpm before reducing uncommanded again to idle. The landing gear impacted the perimeter fence, the horizontal stabilizer impacted a fence pole, and the airplane impacted a road near the airport perimeter. and the airplane came to rest in a field about 1,000 ft from the departure end of the runway. The horizontal stabilizer sustained substantial damage during the accident sequence. A postaccident examination of the airplane confirmed continuity of the crankshaft to the accessory case and valvetrain. The throttle and mixture controls were continuous from the controls in the cockpit to the attachment at the carburetor. Compression and suction were confirmed on all cylinders, and no anomalies were observed inside the cylinders when viewed with a lighted borescope. The air intake was unobstructed, and the exhaust was impact damaged. Both magnetos produced spark from all towers when the propeller was turned by hand. The ignition harness was undamaged, and the sparkplugs exhibited normal wear when compared to the Champion Aerospace Aviation Check-A-Plug chart. The bottom Nos. 1 and 3 sparkplugs were oil soaked. The airplane wing fuel tank caps and filler necks exhibited rust and corrosion. Rust colored granular material was observed in the carburetor fuel inlet fitting and in the carburetor fuel inlet screen. The engine-driven fuel pump was removed from the engine and exhibited corrosion on the internal check valves. The airframe fuel strainer drain control was pulled and the strainer produced a quantity of liquid that contained granular debris. The liquid was tested with water finding paste. The paste color changed to red, indicatingthe presence of water. Liquid drained from the airframe electric fuel pump when the fuel screen cover was removed. The screen contained rust colored debris. The liquid was tested with water finding paste. The paste color changed to red, indicating the presence of water. The oil suction screen and oil filter media were absent of metallic debris. The airport director reported that the airplane was kept outside at a tie down, where it had been kept since 2006. He also provided fuel receipts that showed the last record of fuel being added to the airplane was January 11, 2024. A review of the maintenance performed on the airplane revealed that the most recent annual inspection was completed on April 21, 2025, with an airframe total time of 6,611.0 hours and an engine time since major overhaul of 495.8. The most recent engine overhaul was completed by Lycoming Engines on February 3, 2005, more than 20 years before the date of the accident. The last entry in airframe logbook #4 was dated March 18, 2009. The remaining pages in the logbook were blank. The maintainer who completed the most recent annual inspection provided some loose maintenance entries. The first of those entries was dated March 20, 2023, and the last was the most recent annual inspection. When asked what work had been done during the recent maintenance the owner of the shop that performed the work stated “the fuel system was visually inspected for leaks in lines, fittings, carburetor and gascolator none were noted. Gascolator bowl was removed and the filter was checked, cleaned, and reinstalled, no water or debris noted at this time, and the system was not flushed at this time.” According to Lycoming Engines Service Instruction No. 1009BE: CALENDAR TIME PERIOD TBO All engine models are to be overhauled within twelve (12) calendar years of the date they first entered service or of last overhaul. This calendar year time period TBO is to mitigate engine deterioration that occurs with age, including corrosion of metallic components and degradation of non-metallic components such as gaskets, seals, flexible hoses and fuel pump diaphragms. The airplane was equipped with an Insight G4 engine monitor which was capable of recording data. This was sent to the NTSB vehicle recorders laboratory for data recovery. The data recovered included bus voltage, carburetor temperature, cylinder head temperature, exhaust gas temperature (EGT), fuel flow, fuel used, and outside air temperature. The data showed that during the takeoff roll and initial climb the fuel flow remained relatively constant at about 20 gallons per hour (gph) for about 30 seconds. It then tapered off to about 2 gph over about 30 seconds before rising again to 10 gph for about 5 seconds then dropping to 0 gph. The EGT readings were erratic throughout the accident flight recording.