Accident Details
On August 9, 2022, at approximately 1231 Pacific daylight time, a Piper PA-32-300, registration N841AD, was substantially damaged during a forced landing near Corona, California. The pilot and passenger were not injured. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a personal flight.
The flight departed Corona Municipal Airport (AJO) about 1115 for a local flight. According to the pilot, while returning to AJO and entering the downwind leg, he adjusted engine power to level off and reduce airspeed. The engine did not respond, and cycling the throttle several times produced no change. Unable to maintain altitude, the pilot elected to make a forced landing onto the eastbound lanes of US Highway 91. During the landing flare, to avoid impacting a car, the pilot intentionally stalled the airplane. The airplane landed hard, rotated right (clockwise), and struck a freeway barrier. Both occupants exited, and a postaccident fire ensued.
The pilot reported that he normally turns the auxiliary fuel pump selector switch to the on position before entering the downwind leg when completing a pre-landing checklist. He stated that he did not think he turned on the fuel boost pump switch because he was responding to the loss of engine power and searching for a suitable emergency landing area.
Post-Accident Examination
Postaccident examination revealed that the cockpit and fuselage were largely destroyed by thermal and impact damage. Throttle and mixture control continuity was established from the cockpit to the fuel servo, with full range of motion when actuated by hand. Visual inspection of the fuel system showed continuity from the wing roots to the fuel injectors, though various breaks were observed in both wings' fuel lines, consistent with cuts by recovery personnel and/or impact damage. A torsional twist (kink) was found in the steel braided fuel supply output line from the engine-driven fuel pump to the fuel servo. No visible impact damage to the airframe could account for this twist. The position of the auxiliary fuel pump switch could not be determined due to fire damage.
Further examination of the engine-driven fuel pump showed evidence of a preexisting fuel leak at the case split and corrosion in the input drive seal area. The pump was tested on a stand and maintained/exceeded output fuel pressure at idle and high speeds. However, when the kinked output fuel line was installed and the B-nuts were progressively torqued with a hand tool, the pump pressure decreased until it could no longer maintain adequate output pressure.
The aircraft was equipped with a J.P. Instruments EDM-830 engine monitor, which was recovered and sent to the NTSB Vehicle Recorder Laboratory. Despite heat and fire damage to the exterior, the non-volatile memory chip was removed, installed on a functional lab surrogate unit, and data were downloaded normally. Recorded data from 17:25:00 to 19:30:00 showed changes in engine rpm, fuel flow, manifold pressure, horsepower, oil pressure, and oil temperature consistent with takeoff, climbs, and descent power settings. At about 19:22, reductions in manifold pressure, engine rpm, and fuel flow were observed. At 19:23:36, fuel flow indicated 24.4 gallons per hour, manifold pressure 26.4, and engine rpm 2502. Subsequent data showed manifold pressure increasing to 30.1, engine rpm dropping to 80, and fuel flow varying from 0 to 3.2 gallons per hour.
A review of maintenance records revealed that the fuel servo was replaced on February 20, 2019, but no subsequent maintenance on the engine-driven fuel pump or kinked fuel line was documented.