What happened
On 16 April 2022, at approximately 0834 local time, the pilot of a B58 Baron, registration VH-NPT, was performing a straight-in approach to runway 12 at East Kimberley Regional Airport in Kununurra. During this approach, the pilot declared a PAN-PAN, reporting smoke and a suspected fire within the cockpit. As the aircraft crossed the Ord River, the pilot began to deviate from the runway centerline. The aircraft subsequently struck terrain on the eastern side of the river, roughly 800 m from the runway 12 threshold. The accident resulted in one fatality and one person with serious injuries.
The investigation
The ATSB examined the circumstances of the in-flight fire and the subsequent loss of aircraft control. The pilot noted that smoke and flames emerged from beneath the left side of the instrument panel, specifically below and forward of the circuit breaker panel. While the pilot attempted to use a portable fire extinguisher to suppress the flames, the fire returned aggressively once the extinguisher was removed.
Investigators looked into the acceleration of the fire, noting that the fire spread much faster than expected for the flame-resistant interior materials. The investigation focused on the fuel line serving the cabin heater, which passes through the area where the fire originated. A breach in this line could have allowed fuel to leak into the insulation, acting as an accelerant. While the pilot reported an electrical burning smell and issues with the landing gear system prior to the fire, the post-impact fire prevented a direct examination of the heater line's integrity.
Findings
- An electrical system fault likely acted as the ignition source for the fire.
- The fire was likely accelerated by fuel from the cabin heater supply line.
- The presence of smoke caused the pilot to lose visual reference to the instruments and the external environment, leading to the deviation from the runway centerline.
- The pilot sustained serious burns, and both the pilot and passenger suffered respiratory injuries due to fire exposure.
- The use of a 4-point harness for the pilot provided better impact attenuation, potentially reducing the severity of impact-related injuries.
- The passenger's survivability might have been improved had they been seated in a rearward-facing seat.