N6380A

HISTORY OF FLIGHTOn November 10, 2020, about 1540 Pacific standard time, a Piper PA-38-112, N6380A, was substantially damaged when it was involved in an accident near Grass Valley, California. The pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

Automatic dependent surveillance-broadcast (ADS-B) data obtained from the Federal Aviation Administration showed that the pilot departed Cameron Park Airport (O61), Cameron Park, California, and arrived at University Airport (EDU), Davis, California, about 1100, where he purchased 12 gallons of 100 low-lead aviation fuel.

The pilot departed EDU and flew to an area east of the airport, where he performed numerous maneuvers before proceeding to Yolo County Airport (DWA), Davis, California, before he returning to EDU about 1200.

The pilot departed EDU about 1419 and completed a touch-and-go landing at Oroville Municipal Airport (OVE), Oroville, California. The pilot proceeded southeast at a cruise altitude of 5,500 ft mean sea level. At 1533:49, the airplane passed Nevada County Airport (GOO), Grass Valley, California, about 2 minutes before completing a slight right turn to a southerly heading. About this time, the pilot reported a loss of engine power to air traffic control. The pilot conducted a 180° right turn to the north as the airplane began to descend, followed by a 180° left turn about 2 minutes later, at which point the ADS-B track data ended at 1539:22, approximately 0.3 nautical mile (nm) west of the accident site. Figure 1 shows the airplane’s flightpath on the day of the accident.

Figure 1. Pilot’s flightpath and legs in numerical order

A witness located about 0.1 nm southeast of the final ADS-B data point and 0.3 nm southwest of the accident site reported that he saw the airplane fly over him in a steep, controlled, left turn (see figure 2). He noted that he could not hear the engine and that the airplane sounded like a glider. The airplane then rolled into a level attitude on a northeasterly heading as it flew past the witness in a steady descent and disappeared behind trees. The witness heard the airplane impact the ground about 4 seconds later.

Figure 2. Airplane’s final track based on ADS-B data and witness statement

PERSONNEL INFORMATIONThe pilot’s father reported that the pilot had accumulated about 50 hours in a Diamond DA-20 and 80 hours in a T-6 Texan in United States Navy pilot training. The pilot obtained his instrument rating and commercial pilot certificate at a flight school in San Diego, California, then relocated to northern California about 8 months before the accident. He began accumulating time in the accident airplane, which was owned by his neighbor, with the goal of accruing 500 hours of flight time to transition into air charter operations. During this time, he completed a multiengine rating and began flying with a friend in two different twin-engine airplanes.

The pilot’s logbooks showed that he started flying the accident airplane on October 1, 2020.

AIRCRAFT INFORMATIONThe airplane owner stated that he agreed to loan his airplane to the accident pilot, who would pay for routine maintenance and fuel. The owner flew with the accident pilot for about 12 hours to fulfill insurance requirements, which they completed about 1 month before the accident. He estimated that the pilot flew the airplane for about 20 hours after they stopped flying together. According to the owner, he instructed the pilot not to run either fuel tank under 3 gallons and to assume a fuel burn of about 6 gallons per hour. The owner also advised the pilot to operate one fuel tank as his “margin” and the other as the main tank and to ensure that the fuel tank with the lower quantity was on the pilot’s side when flying alone to “maintain balance.” The owner added that he last flew the airplane on November 7 and recalled that, at the end of that flight, the right-wing tank contained about 6 to 7 gallons and the left-wing tank contained about 3 to 4 gallons of fuel. The owner stated that he advised the pilot to consider switching tanks a couple of times during previous flights.

The investigation found that the airplane was subsequently refueled with 25 gallons on November 9 and 12 gallons on the day of the accident.

AIRPORT INFORMATIONThe airplane owner stated that he agreed to loan his airplane to the accident pilot, who would pay for routine maintenance and fuel. The owner flew with the accident pilot for about 12 hours to fulfill insurance requirements, which they completed about 1 month before the accident. He estimated that the pilot flew the airplane for about 20 hours after they stopped flying together. According to the owner, he instructed the pilot not to run either fuel tank under 3 gallons and to assume a fuel burn of about 6 gallons per hour. The owner also advised the pilot to operate one fuel tank as his “margin” and the other as the main tank and to ensure that the fuel tank with the lower quantity was on the pilot’s side when flying alone to “maintain balance.” The owner added that he last flew the airplane on November 7 and recalled that, at the end of that flight, the right-wing tank contained about 6 to 7 gallons and the left-wing tank contained about 3 to 4 gallons of fuel. The owner stated that he advised the pilot to consider switching tanks a couple of times during previous flights.

The investigation found that the airplane was subsequently refueled with 25 gallons on November 9 and 12 gallons on the day of the accident.

WRECKAGE AND IMPACT INFORMATIONThe wreckage was in wooded terrain at an elevation of about 2,710 ft mean sea level. All major sections of the airplane were accounted for at the accident site. The initial impact point (IIP) was marked by a severed tree that displayed an impact mark about 15 ft from its base. The airplane came to rest 26 ft east of the IIP and was inverted and intact, oriented on a northwest heading.

Both propeller blades remained attached to the engine crankshaft and were each bent slightly toward their blade faces. The blades did not exhibit any nicks, gouges, or chordwise scratching. The fuel selector was found in the LEFT tank position at the accident site. An odor that resembled 100 low lead aviation fuel was observed below the right wing; no odor was observed below the left wing at the accident site. Additionally, no fuel drained from the left tank when the fuel cap was removed. About 5 gallons of fuel was drained from the right-wing during recovery of the airplane, with some evidence of fuel spillage at the accident site. Flight control continuity was traced from the cockpit flight controls to the aileron, elevator, and rudder control surfaces. The elevator trim wheel cable was wrapped twice around the trim wheel drum, consistent with partial nose-up trim, according to the manufacturer. The flap handle was in a position consistent with fully extended flaps.

Both fuel tanks and fuel system lines showed no indication of preimpact anomalies. The selector functioned normally throughout its LEFT, RIGHT, and OFF positions and the auxiliary fuel pump motor could be heard when connected to a battery. Water contamination was observed in the gascolator bowl; however, the left-wing fuel cap had been removed while the airplane was in storage for several months following its recovery from the accident site and the wing had been subjected to frequent rain.

Mechanical continuity was established throughout the rotating group, valve train, and accessory section as the crankshaft was manually rotated with a drive tool. The magnetos produced spark at all four plug leads and most of the spark plugs displayed signatures consistent with normal wear, except for three spark plugs that had some evidence of oil. Examination of the interior components using a lighted borescope revealed no indications of catastrophic engine failure.

ADDITIONAL INFORMATIONPA-38 Fuel System

The airplane was equipped with two fuel tanks: one in each wing. Fuel was directed through a fuel selector located in the center of the engine control quadrant and fuel quantity indicators for the right and left tanks were located on either side of the selector. The fuel selector was equipped with a knob to select the right tank, left tank, and off positions. The fuel was drawn by an electric fuel pump downstream of the fuel selector, which directed fuel to an enginedriven fuel pump then to the carburetor at the engine. The owner stated that the fuel quantity indicators provided an accurate representation of the fuel level. The fuel quantity indicators were not tested.

Fuel Computations

The airplane’s fuel quantity was computed from the last time the fuel levels were observed by the airplane owner 3 days before the accident. ADS-B data was gathered for each subsequent flight completed by the pilot, who was the only person to refuel the airplane after the owner’s observation. A cruise fuel consumption rate of 5 gallons per hour (GPH) was assumed for each flight and did not include the climb from EDU or the descent and climb from Oroville, which were about 1.4 gallons, 0.5 gallon, and 1.4 gallons respectively. Assuming an evenly distributed fuel consumption between tanks between November 7 and the day of the accident, the data showed that the airplane departed on the accident leg with 8-10 gallons in the left tank and 9-11 gallons in the right tank. The computations (without, climbs and descents) showed that about 3.43 gallons would have remained in the left tank and about 11 gallons in the right tank at the time of the power loss had the left tank been selected and the pilot had not switched tanks for the final 80-minute leg that began at EDU. Factoring in the pilot’s climb from EDU, descent to OVE and subsequent climb, the airplane would have had about 1.13 gallons remaining in the left tank at the time of the power loss.

Fuel computations using the owner’s suggested 6 GPH cr...