What happened
On July 29, 2024, a Raytheon Aircraft Company A36, registration N934PC, was involved in an accident at Naples Municipal Airport (APF) in Naples, Florida. The flight was being operated under 14 CFR Part 91 for personal use.
Prior to departure, the pilot performed a preflight inspection, and the engine appeared to operate normally. After taxiing to runway 5 and completing a runup—which showed a 75 rpm drop on each magneto—the pilot began the takeoff roll. During the climb, at approximately 150 feet above ground level, the engine began running rough and suffered a partial loss of power. The pilot responded by lowering the nose and performing a straight-ahead landing on the remaining runway with the landing gear retracted. The pilot was not injured, but the aircraft sustained substantial damage, including buckling to the fuselage and the wing root area.
The investigation
Mechanics examined the engine and found the crankshaft rotated freely with compression present in all six cylinders. The magnetos were correctly timed and produced spark, and the spark plugs showed normal wear, aside from slight oil residue on the lower plugs of cylinders No. 2 and No. 4. The fuel servo and gascolator screens were clear of debris.
Upon inspection of the fuel injectors, the No. 3 injector showed signs of partial obstruction. After cleaning and reinstalling the injectors, testing showed low fuel flow from the No. 3 injector at high power and from the No. 5 injector at low power. A second examination revealed that the No. 2 injector was nearly completely blocked by debris. Subsequent tests showed normal fuel flow through all injector lines when the injectors were removed. Fuel samples from the main tanks were clear, light blue, and free of debris.
Maintenance records indicated that the fuel injection system had been cleaned on July 27, 2024, two days before the accident. Additionally, the fuel flow transducer had been replaced on March 7, 2024.