Three-times Formula One world champion Niki Lauda, regarded as one of the finest racers of all time and who later became a successful airline entrepreneur, has died at 70 after battling declining health.br br Austrian Lauda, won two world championships in 1975 and 1977 with Ferrari and a third in 1984 with McLaren.br br He had a near-fatal crash in 1976 when racing at the Nuerburgring but despite suffering horrific burns, he was soon back in his Ferrari with a modified helmet and went on to claim his second world title.