Rust on items linking truck and trailer, court told

The occupants died on August 7, 2014, when a BP petrol tanker decoupled and hit two cars on the Wodonga-Yackandandah Road.

The Wodonga company that serviced the truck and trailer, Heavy Mechanics Pty Ltd, has pleaded not guilty to a charge of failing to ensure people were not exposed to risks to their health and safety.

Jurors in the Wodonga County Court on Wednesday held items which had connected the truck and trailer, including a nut found on the side of the road after the crash.

The prosecution says the failed nut is central to the case.

IN OTHER NEWS:

Detective Sergeant Darryl Out attended the scene and said the nut was clearly rusted.

Heavy Mechanics director Keith Haire agreed that during services he would regularly decouple the trailer, perform a visual inspection, physically check for movement and run his hands over parts to see if they were loose.

He said there were no signs of movement that would warrant the coupling being disassembled and no damage seen.

A tow eye shaft - sections of which were pulled apart for testing - were also examined by the 12 jurors along with an A-frame that was part of the trailer.

Detective Sergeant Out said there were also areas of rust on the tow eye.

He said the trailer had an automatic failure mechanism which would have applied brakes after decoupling in "a matter of seconds".

Skid marks could be seen where the tyres locked, he said.

Retired Leading Senior Constable Ian Ellis said there were no faults found with the truck, but an issue with the trailer.

"The trailer was in good condition other than the towing hitch," he said.

He said the thread on the nut "should be much more substantial.".

"A lot of that's gone," Mr Ellis said.

Mr Haire gave evidence on the different types of services undertaken at the Kane Road business.

Mechanics worked on two different vehicles for BP.

Mr Haire said he hadn't sought information from tow eye manufacturer JOST regarding its servicing.

He said he would instead service it "using industry standards and experience".

Mr Haire said the nut was tight during the last service.

The trial will continue on Thursday.