Former F1 racing driver and engineer John Miles, aged 74

Former racing driver John Miles, right, who has died at the age of 74, was best known for his work with Lotus, both on and off the track.

He competed in a series of Formula One world championship races before quitting the team following the death of its leader in a crash in 1970.

A qualified mechanical engineer, he was later involved in the development of the Ford Focus car and wrote a column for the motoring magazine Autocar.

The son of the actor Sir Bernard Miles, John made his F1 debut on July 6 1969 in the Lotus 63 four-wheel drive F1 car, for which he was the official Team Lotus test driver.

His racing career had begun in earnest in 1963-64 when he was crowned overall champion in the Redex Sports Car Championship, driving a front engine Diva GT.

In 1966 he won the Autosport Championship in a Lotus Elan 26R, after finishing victorious in 15 of his 17 races.

He won four international F3 events in 1968, before taking the wheel of the Lotus 63 4WD after world champion Graham Hill and Jochen Rindt both refused to drive it, regarding it as a death trap.

Miles finished only once in five grands prix in 1969, but was promoted to number two Lotus F1 driver behind Rindt for the 1970 F1 season after Graham Hill broke his legs and did not return to the team.

The Austrian driver Rindt won five races to claim the 1970 F1 World Drivers Championship. However, the title was awarded posthumously after he was killed during practice for the Italian Grand Prix in September .

Miles left the team immediately after the accident and went on to sign for BRM in 1971, working mainly as a test driver.

He later made a name for himself working for Lotus’ road car division and wrote a column, Miles Behind The Wheel, for Autocar magazine.

He also continued to tutor and support young engineers and worked as an independent consultant until his death.

He died on Sunday after a stroke.