What happened
Following a missed approach at the Grand Canyon Airport, the crew diverted the aircraft type to Bullhead City Airport. During the flight, the pilots encountered light icing conditions, noting that approximately 1/8 inch of ice had gathered on the wings. To manage this, the crew utilized the deice boots to remove the accumulation.
As the aircraft was on a 3-mile final approach with the landing gear and flaps deployed, both engines experienced a flameout. The aircraft subsequently performed an off-airport landing, resulting in the total destruction of the aircraft type.
Findings
Investigation into the event revealed that while the pilots observed ice on the wings, they did not notice any ice buildup on the propeller spinners. Crucially, the crew failed to engage the engine override ignition systems as mandated by the flight manual. According to the manufacturer's procedures, these systems must be activated when flying through visible moisture at temperatures of +5 degrees Celsius (+41 degrees Fahrenheit) or lower to protect against engine flameouts caused by ice ingestion.