Three-times Formula One world champion, racing team manager and airline businessman Niki Lauda has died at the age of 70, his family said in a statement.

The Austrian, who was considered one of the best racing car drivers of all time, had undergone lung transplant surgery in August to try to repair injuries suffered in a horrific fireball crash in 1976.

"With deep sadness, we announce that our beloved Niki has peacefully passed away with his family on Monday," Lauda's family said in the statement.

The transplant operation forced him to remain hospitalized for several months and in Jan. he had to be readmitted for 10 days because of influenza he contracted over Christmas in Ibiza, Spain, where the former racing driver had his second residence.

Andreas Nikolaus Lauda was born on Feb. 22, 1949, in Vienna into a wealthy family with links to industry.

His family disapproved of his racing ambitions, so Lauda took out a large bank loan and financed himself into Formula Two at the wheel of a March racing car. His ability soon saw him promoted to F1.

"His unique achievements as an athlete and entrepreneur are and will remain unforgettable, his tireless zest for action, his straightforwardness and his courage remain a role model and a benchmark for all of us, he was a loving and caring husband, father and grandfather away from the public, and he will be missed," his family's statement added.

Lauda had already had two kidney transplants in 1997 and 2015, the second being an organ donation from his wife Birgit.

Lauda's F1 career began in 1971 and he won his first World Championship, the sport’s highest level of international competition, in 1974 driving for Ferrari.

F1 at that time was almost certainly the most dangerous sport in the world, claiming the lives of drivers at almost every major race.

“F1 is simply about controlling these cars and testing your limits,” Lauda told the United Kingdom's The Telegraph newspaper in 2015. “This is why people race — to feel the speed, the car and the control. If in my time you pushed too far, you would have killed yourself. You had to balance on that thin line to stay alive.”

At the 1976 German Grand Prix on the Nurburgring race track, he was involved in an accident when his Ferrari veered off the track, smashed into the embankment and burst into flames, with Lauda trapped in the burning wreckage.

Fellow drivers Arturo Merzario, Brett Lunger, Guy Edwards and Harald Ertl arrived at the scene moments later, but Lauda suffered severe burns to his head, lungs and bloodstream before Merzario was able to yank him from the blazing car.

The helmet Lauda had been wearing had slid off in the impact and exposed his head to the conflagration.

“Such were his injuries, which included facial burns and flame inhalation, that he was given the last rites,” F1 said in a statement. “At one stage he was not expected to survive. But by his own admission, he began an incredible fight back to life when he heard the priest administering those rites.”

Six weeks later, still wearing bandages and in pain, he was racing again and managed to come second in the championship just one point behind the winner, James Hunt of the UK. Lauda had missed just two races that season.

In Sept. 1979 Lauda informed Bernie Ecclestone, his Brabham team principal, that he was going to retire and he left to found Lauda Air, his own charter airline in Austria.

But he returned in 1982, joining the McLaren team with which he won his last world championship two years later. The following year he withdrew from F1 as a race driver.

Lauda continued his involvement in motorsport filling management positions, first as an adviser to Ferrari (1992-1997) and then for Jaguar and Mercedes.

He is credited with having persuaded current World Champion Lewis Hamilton to join the German team.

Lauda is survived by his second wife Birgit and their twin children Max and Mia. He also had two adult sons from his first marriage, Lukas and Mathias. Mathias is also a race car driver and his brother Lukas is his manager.