CEN19FA279

The single-engine airplane had undergone recent maintenance, including the installation of a field overhauled engine and a three-bladed propeller. The pilot and pilot-rated passenger were conducting a maintenance check flight. One witness reported that the airplane took off normally, but when it reached between about 200 to 300 ft above ground level, it stopped climbing. Another witness reported that he did not hear the engine but that he could not remember whether the propeller was turning. The accident engine was a modification to the airplane’s original configuration. Such a modification is typically recorded on a Federal Aviation Administration Form 337, “Major Repair and Alternation,” and adopted by a field approval. However, neither the form nor maintenance records regarding the installation of the modified engine were found during the investigation. A smart phone recorded two videos from inside the airplane. One of the videos captured the accident flight just after takeoff. Several seconds later, a decrease in engine sound was heard, followed by a momentary warning horn. One of the occupants then stated, “we’re stalling,” followed by the sound of the stall warning horn and impact with terrain. Examination of the airplane revealed substantial damage to the wings and fuselage. During examination of the engine, the air filter element was found displaced and lodged in the intake. The metal screen used to hold the filter element was found improperly installed. The evidence indicates that the improper installation of the metal screen allowed the filter element to become displaced and subsequently lodged in the intake, which blocked the intake air and resulted in a total loss of engine power.

The airplane was originally equipped with a Continental IO-520-A engine and a McCauley two-bladed propeller. The airplane was modified by the installation of a Continental IO-550-F engine and a McCauley three-bladed propeller. The engine and propeller modification is typically recorded on a Federal Aviation Administration (FAA) Form 337, “Major Repair and Alternation,” and adopted by a field approval. Neither the form nor maintenance records regarding the modification were found during the investigation. On August 20, 2019, about 1118 eastern daylight time, an Aero Commander (Meyers) 200D airplane, N200HS, was substantially damaged when it was involved in an accident at the Livingston County Spencer J Hardy Airport (OZW), Howell, Michigan. The pilot and pilot-rated passenger were fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The airplane had undergone recent maintenance, during which the passenger had installed a field overhauled engine and a three-bladed propeller. The pilot, who was seated in the left seat, and passenger, who was seated in the right seat, were conducting a postmaintenance check flight. The accident flight was the second flight of the day in the accident airplane. Before the first flight, the airplane was filled with 34.4 gallons of fuel. It could not be determined if any adjustments or maintenance items were accomplished on the airplane after the first flight and before the accident flight. One witness reported that the airplane took off normally from OZW, but when the airplane was between about 300 and 400 ft above ground level, it stopped climbing. One witness reported that it looked like the airplane tried to turn back to the runway before entering a rapid descent. Another witness reported that he did not hear the engine but that he could not remember whether the propeller was turning. A review of the airport security video that captured the airplane’s departure revealed that it began climbing but then stopped. The airplane then entered a slight descent before it disappeared out of the camera’s view. Another camera captured the airplane rapidly descending just before it impacted terrain. A smart phone recorded two videos from inside the airplane. One of the videos captured the accident flight starting just after takeoff. Several seconds later, a decrease in the engine sound was heard, followed by a momentary warning horn. One of the occupants then stated, “we’re stalling,” which was followed by the sound of the stall warning horn and impact with terrain. The Michigan Medicine Pathology and Clinical Laboratories, Ann Arbor, Michigan, under the authority of the Livingston Country Medical Examiner, conducted an autopsy on the pilot. The cause of death was determined to be "multiple traumatic injuries.” The FAA’s Forensic Sciences Laboratory, Oklahoma City, Oklahoma, conducted toxicological testing of specimens from the pilot. The tests were negative for ethanoland carbon monoxide and positive for doxylamine and dextromethorphan, which are over-the-counter medicines often used to treat cold or allergy symptoms. The airplane was equipped with a JPI engine monitor, and the data were downloaded. The airplane impacted terrain and came to rest about 600 ft beyond the departure end of runway 13. Examination of the airplane revealed that the forward cabin/cockpit area, fuselage, and both wings exhibited impact damage. All the major airplane components were located at the crash site. Two of the three propeller blades came to rest in the main wreckage path, and the third blade remained in the propeller hub and engine. No postcrash fire ensued. Control continuity was established from the cockpit to the elevator and rudder. Aileron continuity was continuous from the cockpit to the left and right aileron bellcranks. The landing gear and flap handles were in the “down” position, and damage to the wings near the landing gear struts was consistent with the gear being extended during the accident. The front seats were equipped with only a lap belt. Examination of the engine revealed that the air filter element was displaced and lodged in the intake tube (see figures 1 and 2). Figure 1: Engine intake Figure 2: Engine intake and air filter element The engine crankshaft was rotated by hand. Compression and suction were obtained for all cylinders at the top spark plug openings. Internal engine continuity was confirmed through the valve train and to the accessory section. When the engine was rotated, a snap/click sound was heard from two magneto impulse couplings, and spark was observed from each top ignition lead. The engine-driven fuel pump was intact, and the drive shaft rotated freely when operated by hand. The top set of sparkplugs exhibited dark-colored combustion deposits and normal electrodes. Cylinder Nos. 4 and 6 exhibited evidence of carbon fouling.