London - If practice makes perfect, Harry Kartz should be a flawless driver.

After all, the 100-year-old Bomber Command veteran has been on the road since 1927.

But, as a TV documentary profiling Britain’s oldest motorists reveals, his skills may alarm some fellow drivers.

The great-grandfather from Solihull is shown forgetting his indicators, mounting the pavement – shouting “b***** the kerb” as he does so – and even drifting into the wrong lane during the programme.

Because compulsory tests were not introduced until 1935, he has never had to take a driving exam in 86 years on the road. Although drivers over 70 need to reapply for their licences every three years, their skills and their eyesight are not automatically reassessed and it is up to them to confirm they are still capable.

There are 209 motorists aged 100 and over still on Britain’s roads.

Asked if he would ever give up driving, Mr Kartz, a former chairman of Aston Villa football club, replied: “When I’ve got to the stage when I’m not ready [to react to] other people’s actions. I don’t want to drive like an old man.

“I’m not an old man. I’ve got my licence until 2016 – but I don’t think I’ve got a licence for myself until 2016, I think I shall be gone before then.”

Mr Kartz, whose wife Dorothy died in 2012 after 72 years of marriage, admits writing off three cars in his lifetime, but insists he is safer now than he has ever been. Although he has never had his driving formally assessed, he is often put through his paces by his son John, 69. He told the programme that “children of ageing drivers do have a responsibility to check everything is going well”, but gave his father the all clear, despite watching him mount the kerb and drift into the wrong lane. Mr Kartz is one of the motorists starring in ITV’s 100 Year Old Drivers.

Also featured is retired teacher Mary Walker, 100, who admitted flouting speed limits, saying: “It’s exhilarating, going fast. People that drive slowly, they frustrate you. How fast do I like to go? I don’t think I ought to answer that.”

Searson Thompson, 102, who lives in Aberdyfi, Wales, said he would be stranded without his car. “I drive because I’m completely self-sufficient,” he said. “If I were to stop driving now, I’d vegetate.”

The number of drivers keeping their licence past 70 is rising, up from 3.9 million in 2012 to 4.1 million this year. Those over 90 still driving has risen from 71 259 in 2012 to 77 423.

Though older drivers are viewed as more dangerous, this is not borne out by the figures. In 2012 one out of every 181 licence holders under 30 was the driver in an accident, compared to one out of every 526 motorists over 70.

The DVLA said: “All drivers over 70 have to renew their licence every three years and have to tell DVLA about any conditions which might affect their driving.”