Aviation safety investigations & reports

de Havilland Canada DHC-6 SERIES 320, VH-FNU

Investigation number:
Status: Completed
Investigation completed


The crew of the DHC-6-320 aircraft reported that during descent to Cairns they smelt smoke in the cockpit. They then noticed the battery load meter was at maximum discharge and the right generator light was illuminated. The left generator switch was moved to the OFF position, however, the generator remained on-line.

Subsequent in-flight inspection revealed that the smoke was coming from behind the right cabin roof panel; which had begun to melt and bubble. The pilot in command then contacted Cairns approach control reporting a fire in the cabin and the aircraft was cleared to track direct to Cairns. The co-pilot accessed the cabin fire extinguisher and extinguished the fire. At approximately 4NM from the airport, the co-pilot reported that the fire was an electrical fire and had been extinguished. After landing, the crew stopped the aircraft on the runway and shut down the right engine to allow the fire fighters access to the cabin. Following confirmation that the fire was extinguished the aircraft was taxied to the terminal.

Investigation by the owner's maintenance organisation found that the left reverse current relay had severe heat damage. Other components and wiring near the left reverse current relay were also heat damaged. The reverse current relay was disassembled by the maintenance organisation's engineers, but they were unable to determine the reason for the failure due to the severity of the heat damage.

The Bureau did not conduct an on-site investigation of this occurrence.

General details
Date: 20 May 2000   Investigation status: Completed  
Time: 1417 hours EST    
Location   (show map): 28 km E Cairns, Aero.    
State: Queensland   Occurrence type: Fire  
Release date: 24 August 2001   Occurrence category: Incident  
Report status: Final   Highest injury level: None  

Aircraft details

Aircraft details
Aircraft manufacturer de Havilland Canada  
Aircraft model DHC-6  
Aircraft registration VH-FNU  
Serial number 286  
Type of operation Aerial Work  
Damage to aircraft Minor  
Departure point Mackay, QLD  
Departure time 1119 hours EST  
Destination Cairns, QLD  
Crew details
Role Class of licence Hours on type Hours total
Pilot-in-Command ATPL 950.0 13000
Last update 13 May 2014