Mystery continues to shroud the cause of a horror Northern Territory crash in which a family of six died in a 'fireball', with a coroner finding it could have been due to a catastrophic malfunction or a medical episode.
Coroner Elisabeth Armitage this week found that the crash occurred when a family's Pajero suddenly swerved into the path of an oncoming road train on a flat stretch of the Stuart Highway near Pine Creek in September last year.
However she said it remained undetermined why the car, being driven by a 34-year-old father, suddenly and violently strayed onto the wrong side of the road.
Ms Armitage said it may have been caused by the Pajero suffering sudden and catastrophic mechanical failure or due to the driver suffering a medical episode.
She said that the driver of the Kenworth prime mover, which had three trailers attached, was not at fault.
'The crash occurred as a result of the Pajero violently veering from its lane directly into the path of the oncoming road train,' Ms Armitage said.
'With no definitive evidence to support any particular theory, crash investigators could only speculate as to why this occurred.'
The coroner's report painted a grim picture of the scene after the man, woman and four children - aged nine, five, four and one - perished in a fireball and their 'charred' remains were found in the debris and roadside.
A family of six were killed after their Pajero swerved into the path of this road truck
The road train and the Pajero exploded into a fireball following the impact
The youngest child was thrown from the vehicle and it was unclear where they were seated in the car, the coroner said.
'An inspection of the metal seat belt clips remaining after the fire and the location of the body of one child would suggest that the driver and the front passenger were wearing seatbelts but the four children were not,' Ms Armitage said.
The male driver and his partner, who was the front-seat passenger, were seen drinking at a Katherine pub just under five hours before the accident.
The man was seen on CCTV drinking six beers and a premixed spirit, the coroner said in her report. However Ms Armitage said it was unlikely that drink-driving had contributed to the crash.
'Given his consumption of alcohol before departure, the driver of the Pajero may have been intoxicated and may have lost control of the vehicle through fatigue, inattention, loss of consciousness or a combination of these factors,' she said.
The Pajero (pictured) violently swerved onto the wrong side of the road, a coroner has said
A family of six died in the while two people inside the truck survived
'However, crash investigators considered this unlikely as empirical evidence suggests that in such circumstances a vehicle is more likely to drift from its lane rather than veer sharply as occurred in this crash.'
The man did not hold a driver's licence, having been disqualified in 2013 and it had not been renewed.
The 2009 Pajero crossed into the path of the road train 'without any warning' when the two vehicles were approximately 30-40m apart.
The truck driver locked his brakes but was unable to avoid the collision, which launched the Pajero into the air.
'The impact caused the Pajero to explode and burst into flames,' the coroner said.
The crash caused the truck to jack-knife and tip onto its side.
The crash was the deadliest the Northern Territory had seen in 16 years (the truck is pictured)
The truck had just refuelled and the driver and his co-driver, who was sleeping in the cabin, managed to crawl to safety as the truck erupted into flames.
The driver suffered multiple broken ribs and a punctured lung.
'Due to the extensive crash and fire damage sustained by the Pajero it was not possible for a comprehensive mechanical inspection to be carried out,' Ms Armitage said.
'There is no evidence to either suggest or discount that a mechanical fault contributed to or was the cause of the crash.'