A lorry driver died when his vehicle smashed into the back of another HGV on the A14 near the Catthorpe Interchange, despite the efforts of other motorists to rescue him, an inquest heard.
Wilfred Nightingale was 51 years old when he died on July 26 last year.
His inquest was held in Kettering last Thursday.
Witnesses described how Mr Nightingale, who was from Walsall, was in a row of traffic which was slowing because of heavy traffic as it approached the Catthorpe Interchange on the westbound carriageway.
Mr Nightingale’s lorry smashed into the back of another HGV, pushing that lorry into a car in front of it, which in turn also struck another car.
The force of the crash shunted the lorry in front of Mr Nightingale’s vehicle forward by between 30 and 40 metres.
A fire started underneath Mr Nightingale’s lorry, and his cab had been forced inside the trailer of the other lorry.
A number of motorists stopped at the scene to try to rescue Mr Nightingale from the cab, but were unable to open the doors.
In a statement read out at the inquest, Birmingham man Sean McGuigan said: “The cab was right inside the trailer of the lorry in front.
“I did not think the driver would have survived the crash. We could not open the passenger door or the driver’s door. One man got a Stihl saw from his vehicle and managed to cut through the lock.
“Someone got into the cab but said it was too late.
“Smoke was filling the cab the whole time we were cutting from a fire underneath the lorry and several people used fire extinguishers.
“It probably took between five and 10 minutes to get into the cab.”
Police accident investigator Martin Abbott said there was nothing wrong with either Mr Nightingale’s vehicle or the road condition which would have contributed to the accident.
He said: “Mr Nightingale may have failed to observe the matrix warning signs warning about queues or he could have been distracted by something else either inside or outside the cab.”
Pathologist Pippa Stocks said Mr Nightingale died of chest and abdomen injuries, and not from smoke inhalation as he had very little soot in his airways.
Coroner Anne Pember recorded a verdict of accidental death.