Accident Overview
On November 7, 2023, at 1510 eastern standard time, an Aero Commander 500B, registration N118PW, was substantially damaged during a forced landing near Jackson, Michigan. The pilot, who was the sole occupant, was uninjured. The flight was conducted as a positioning flight under Title 14 Code of Federal Regulations Part 91.
Sequence of Events
Approximately 30 minutes after departure, the pilot observed erratic and low fuel pressure on the right engine. In response, he descended the airplane from 7,000 ft to 5,500 ft, reduced engine power, and activated the fuel boost pump. Upon reaching 5,500 ft, fuel pressure returned to normal and the engine produced full power.
About 15 to 20 minutes later, similar symptoms recurred on the same engine. The pilot again reduced engine power, turned on the fuel boost pump, and descended to 3,500 ft, after which engine power and fuel pressure were restored.
Approximately 15 miles from the destination airport, fuel pressure to the right engine was lost, causing the engine to surge and produce partial power. Shortly thereafter, left engine fuel pressure was also lost, and both engines produced partial power, with manifold pressure between 12 and 15 inches and fuel pressure below 10 psi. The airplane could not sustain level flight, prompting the pilot to perform a forced landing in a field. During the landing, the airplane sustained substantial damage to the left wing.
Postaccident Examination
Initial examination revealed only residual fuel drained from the fuel system. No security seal was placed over the fuel tank filler ports, and the airplane remained unmonitored in the field until an engine run and subsequent examination on November 29, 2023.
The later examination of the fuel system, including airframe fuel filters and flow dividers, found no debris or contaminants. After leveling the airplane with jacks, approximately 27 gallons of 100 low lead aviation fuel were drained, which contained no contaminants. About 6 gallons of fuel were added, and both engines started and ran without anomalies that would preclude normal operation.
Testing of the fuel quantity sending unit (The Liquidometer Corp., part number EA515B-1404M) indicated full at varying levels down to empty actual fuel quantity.
Bench testing of the fuel boost pumps, fuel servos, and the fuel manifold valve assembly with attached lines and fuel nozzles revealed no anomalies.