CEN25LA225

According to the flight instructor, while on final approach to the runway the engine experienced a loss of power, and he executed a forced landing to a wooded area near the airport perimeter. The airplane impacted trees which resulted in substantial damage to both wings, the fuselage, and the stabilator. Postaccident examination of the airplane’s exhaust system revealed that a steel baffle of the muffler flame tube assembly had failed and blocked at least 95% of the single exhaust outlet port (tailpipe). Deformation damage was noted to the remaining flame tube and the steel baffle which indicated that the failure had been present for an unknown period of time before eventually blocking the exhaust path. There were no other mechanical malfunctions or failures that would have precluded normal operation.

On June 26, 2025, about 1130 central daylight time, a Tecnam P2010 airplane, N258CM, was substantially damaged when it was involved in an accident near Temple, Texas. The flight instructor and student pilot were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 instructional flight. The flight instructor reported that he had completed a preflight inspection, engine run-up, and two touch-and-go landings with no anomalies noted. During the third traffic pattern, while on the downwind leg, the flight instructor switched the fuel selector from the left tank to the right tank. He then verified that the electric fuel pump was on, and the engine instruments were indicating normal. While configured for landing on final approach, the flight instructor noticed an uncommanded change in manifold pressure. He took over the flight controls from the student pilot and moved the throttle lever full forward with no change to the manifold pressure. The flight instructor reported that there were no associated warning or caution crew alerting system (CAS) messages. The flight instructor switched the fuel selector to the left tank in an attempt to restore engine power; however, there was no change. Unable to make the runway, the flight instructor executed a forced landing into a wooded area near the airport perimeter. During the forced landing, the airplane impacted trees which resulted in substantial damage to both wings, the fuselage, and the stabilator. A postaccident examination of the engine revealed a blockage of at least 95% of the single exhaust outlet port as seen in figure 1. A functional engine test run was performed with the blockage present. The engine started without hesitation; however, the engine ran rough with fluctuating rpm. Following the functional engine test, the tailpipe was cut, and the blockage was removed. The piece that was removed was consistent with the steel baffle plate from the exhaust muffler flame tube assembly inside the muffler. A second functional engine test run of the engine was conducted with the blockage removed. The engine started without hesitation and ran at various rpms with no anomalies. Figure 1. Engine exhaust port with blockage as found. Further examination of the muffler revealed that a majority of the perforated flame tube was not present. The remaining flame tube and the steel baffle plate exhibited mushroom deformation. The muffler was original to the engine and had been in service about 1,224 hours. On September 19, 2025, Tecnam published Service Bulletin (SB) 937-CS “P2010 Lycoming Exhaust Muffler Flame Tube Inspection,” which stated in part, “Following an occurrence report involving a Tecnam P2010 aircraft equipped with a Lycoming engine, Tecnam has identified a potential risk concerning the structural integrity of the flame tube located within the exhaust muffler. If not addressed, this condition could result in a partial or complete obstruction of the exhaust system,potentially leading to engine malfunction or stoppage”. On February 2, 2026, the European Union Aviation Safety Agency issued Airworthiness Directive (AD) 2026-0023 concerning the safety issue which required repetitive inspection or an acceptable method of compliance/terminating action. On March 31, 2026, the FAA issued AD 2026-07-05 concerning the safety issue which required repetitive inspection or an optional terminating action.