Maximum attack - the day Rosberg averaged 160mph around Silverstone

“I got carried away, and that shouldn’t be the case if you want to survive. But it only happened that one time…”

Keke Rosberg was a driver with a reputation for laying it all on the line, but in an extraordinary qualifying session for the 1985 British Grand Prix at Silverstone he pushed himself further than he’d ever been before - all in the pursuit of previously unattainable speed.

It all began at a pre-meeting tyre test at the fearsomely quick Northamptonshire track, which saw drivers lapping at an average speed just below 160mph - a mark that had never been surpassed in F1 history, but one that could surely be attained in full qualifying trim with the stickiest of tyres and turbo engines cranked to the max.

Sure enough, when running got underway on the Friday of the Grand Prix some weeks later the drivers began to get agonisingly close the much vaunted velocity, with Rosberg, propelled by Honda’s brutal 1,000+ horsepower RA163-E turbo engine, leading the charge on 159.668mph in his Williams FW10.

But it wasn’t until final qualifying on the Saturday that things really heated up.

With rain clouds hovering menacingly above, McLaren’s Niki Lauda and Alain Prost, Brabham’s Nelson Piquet, Williams’ Nigel Mansell and Lotus’s Ayrton Senna and Elio de Angelis all headed out to test their mettle, but none of them could get close to the mark.

The stage was set for Rosberg.

The swashbuckling Finn was already on the limit as he gunned it through the Woodcote chicane - conceived in 1975 to reduce speeds but now being taken (somewhat ironically) in excess of 125mph - and raced across the start-finish line to begin his lap. There was to be no let-up in commitment.

“The crowd rose as he came through the bends and he looked just like he was low-flying,” Silverstone announcer Keith Douglas memorably recalled. “The car looked like an airplane, twitching as it cornered. Quite incredible! It was almost as if the car was off the ground. It lives in my memory as one of the most outstanding sights I’ve seen yet.”

Rain had begun to steadily fall as Rosberg hustled his bullish yellow, blue and white machine out of Abbey and back towards the beginning of the lap, but the future world champion - who rather inconceivably was also suffering from a slow puncture - pressed on regardless.

He eventually swept across the line in 1m 5.967s - an incredible average of 160.007mph (257.506km/h) for the 2.93 mile circuit and a new high water mark for Grand Prix machinery.

There was still plenty of time to go in the session, but with the track now more than a little greasy it appeared that Rosberg’s provisional pole position - and new lap record - would remain unchallenged.

However, as anyone who has been there knows too well, the weather at Silverstone can change in a heartbeat, and it wasn’t long before the sun reappeared and began rapidly drying the track. With scant minutes of the session remaining, Senna, Piquet, Mansell et al bolted on fresh rubber and returned to the track. Then, much to everyone’s surprise, so did Rosberg.

“It was just plain silly to go and play again when I was already half a second ahead on pole,” Rosberg would explain later. “But I just couldn’t resist it because I thought we could go a lot quicker - and we did...”

Just as he had on his first flyer, Rosberg approached his final lap with maximum attack, his car wriggling, sliding and spewing sparks as he wrung out every last drop of performance. He’d stop the clocks at 1m 5.591s for an average speed of 160.924mph.

“It was probably one of the few occasions when I felt I had lost my self-control,” said Rosberg on reflection. “I should have stayed in the garage and said: ‘I’ve got pole, thank you very much.’ But sheer enjoyment overtook professionalism…”

Despite his qualifying heroics, Rosberg’s weekend would ultimately end in disappointment as he retired from the race with exhaust problems while running in third. But thanks in part to circuit reconfigurations at Silverstone, it would be another 17 years before the Finn’s monumental average speed record was surpassed, by Juan Pablo Montoya during qualifying at Monza in 2002.

Appropriately enough the Colombian was also driving a Williams.