Banapa Avatea of Papakura held back two lanes of southbound peak-hour traffic with his car for 8km on State Highway 1 between Auckland and Hamilton yesterday morning to prevent other motorists being crushed by the out-of-control heavy vehicle, which was carrying a digger.
Then he and another motorist managed to halt the wildly veering truck as it crashed on the side of the road and Mr Avatea helped to revive the diabetic driver.
Mr Avatea, who is head of Huntly West School, said the drama began as he was making his daily commute to work - with his 5-year-old son Jordan in the back - about 7am.
"There was a truck in front of me and he appeared to be going quite slow. Cars were overtaking him but then I saw he was sliding to the right and collecting barriers.
"I thought to myself, 'That's not right', so I accelerated and came up beside him so I could look into the cab. I saw the driver was hunched over the wheel. It appeared he was either asleep or had a heart attack."
The truck, which was travelling about 20km/h, was smashing into barriers on either side of the road, "a bit like a pinball".
"I tried tooting but he wasn't responding. That's when I got in behind him and followed him down towards Rangiriri."
Mr Avatea called 111, turned on his hazard lights and headlights and drove in the middle of the two southbound lanes to prevent other cars passing.
"I stayed behind him and spoke to the dispatcher, I think for about 12 minutes, just letting her know where we were and what was happening and basically just trying to keep the traffic behind me," he said.
"There was heaps of traffic ... but I certainly wasn't worrying about the people behind me, I was thinking about the guy in the truck."
Eventually, as the truck neared Rangiriri, it crashed hard into a barrier and slowed down.
"I got out of my car and a man two or three cars back came out and we both opened the door to the cab. He applied his hand to the [foot] brake and I jumped into the cab and pulled up the handbrake and the truck was stopped."
Mr Avatea said the driver, who he suspected had been jolted awake by the impact, was "very dazed and a bit spacey". He initially suspected a heart attack but the man did not appear to be having chest pains.
Having done a first-aid course, Mr Avatea asked the driver if he was diabetic. "He said yes and then I looked in his bag, found that he had a banana and gave it to him because I wanted to get some sugars going. We gave him a muesli bar as well ... and found he had insulin."
Mr Avatea did not have to inject the man because a paramedic arrived.
Not seeking plaudits for his actions, Mr Avatea left without giving police his details and went to work.
He said he did not feel he had acted heroically. "The thing is, we were just worried about the man in that truck and we just really wanted to make sure he was okay.
"It's something we try to teach the kids in our school; to look after each other and to look after our community and that's all I was trying to do."
Waikato district road policing chief Inspector Freda Grace said Mr Avatea prevented a potential tragedy.
"When you consider the risks posed to other motorists, let alone to the roading contractors working on the road works at Rangiriri, we could very easily have been dealing with a tragedy," she said.
Police would look at ways of recognising the actions of Mr Avatea and the other motorist who intervened.
The truck driver, thought to be in his early 30s, has been working for Hiab Transport in Pukekohe for the past three years.
Director Craig Morris said the driver was initially taken to hospital.
"He was back here in my office about three hours after the accident. He was as good as gold."
He was now waiting for clearance to return to work. He remembered nothing other than hitting a barrier.
Mr Morris said the company had been aware of the man's medical condition, for which he was required to get a medical clearance every two years to hold a heavy traffic licence.
