Experienced instructor Stephen Hoare, 37, and his tandem passenger Alex Welling, 32, died while skydiving at Goulburn airport, in southern NSW, on June 27, 2021.
SafeWork NSW has charged Goulburn Flight Training Centre and its sole director Attilio Giovanni Ferrara, also known as John Ferrara, with two counts each of breaching workplace safety duties.
Ferrara is facing a 10-day judge-alone hearing in the NSW District Court in Sydney.
A short GoPro video taken by a skydiver who was with the pair showed Mr Welling smiling excitedly as he moved towards the open door of the plane, strapped to Mr Hoare.
The men were captured sitting on the edge of the open door for a few seconds before they attempted to launch.
The vision showed a black strap getting caught on the exterior of the plane, leaving the men dangling upside-down mid-air.
One of the men can be heard swearing before the camera follows the course of the skydiver who went on to land safely.
The workplace watchdog's barrister Darien Nagle said a metal step had recently been added to the Cessna aircraft, owned by Ferrara's son's company, to assist with tandem skydives.
The trial would hear evidence the risks of snagging on the step had been identified in the flight training centre's own documents, Mr Nagle said.
He said there was no "buddy check" carried out on the men's equipment before the jump, which could have identified the loose webbing that became snagged.
"It was always known and obvious that these types of steps, along with webbing that hadn't been buddy-checked, could lead to catastrophic results," Mr Nagle told the court in his opening address.
The addition of steps on Cessna skydiving planes was common practice across the industry to help launch parachuters clear of the aircraft.
Similar metal steps were removed from other planes after the men's deaths.
"It is, of course, an absolute tragedy these types of safety measures have to be taken after an incident like this," Mr Nagle said.
The men's families left the courtroom while footage of the snagging incident was played.
Barrister Maurice Baroni, representing Ferrara and his company, indicated there would be parts of the evidence in dispute, including whether the flight centre was correctly identified as the corporate defendant.
Under cross-examination, SafeWork NSW inspector Narelle O'Brien acknowledged several of the company's employees referred to it as Adrenaline Skydive rather than Goulburn Flight Training Centre.
But she nominated the centre as the corporate defendant, based partly on documents that identified it as the entity that paid various skydiving instructors.
The trial continues before Judge Andrew Scotting.
