The 42-year-old father was at the wheel of a black Nissan Skyline that veered out of control off a roundabout at the fork of Farmborough Road and Waples Road, about 7.50pm.

It t-boned a blue Hyundai i30 at speed, with the force of the impact pushing the side of the car almost into the centre console.

Mr Arnold’s 18-year-old son was travelling in the front passenger seat and, with another 18-year-old man in the back seat, walked away virtually unscathed. 

A fourth passenger, a 17-year-old boy, was trapped for almost three hours as rescuers removed multiple parts of the car in a bid to free him.

He was airlifted to St George Hospital in a serious but stable condition.

As at Friday evening, he remained at the hospital in a stable, according to the health service. 

The Mercury understands Mr Arnold, a father of three, was engaged to be married. 

On social media, friends have paid tribute to “a great bloke” and a “best mate” who was “one of a kind”. 

He appeared in the pages of the Mercury in December, when his seven-year-old daughter Summah Arnold helped to avert a drowning off the coast at North Wollongong. 

An off-duty paramedic was among those who came to his immediate aid on Thursday night. 

A witness to the aftermath of the crash, Haylie Staff, said nothing could be done to save his life. 

“The [Skyline] driver was already unconscious. His passenger was unconscious, but another gentleman here brought him around,” she said. 

“The bloke behind him in the back, got him out too. 

“But we couldn't do much for the driver. He passed away, pretty much straight away.” 

“I was trying to keep the one that’s trapped now, calm. He was very, very scared, screaming to hurry up and get him out.” 

The 55-year-old driver of the Hyundai i30 was treated at the scene, alongside his 15-year-old son.

Both were taken to Wollongong Hospital with non-life threatening injuries.

The aftermath of the crash was witnessed by a large number of residents. With debris and oil across the road, the street was closed for at least five hours as fire crews got to work.

Officers attached to Lake Illawarra Local Area Command established a crime scene and have begun an investigation into the circumstances surrounding the crash.

A report will be prepared for the information of the Coroner.