IT was a grey, damp, April day in Baden-Wurttemberg which was to become a black one. Under leaden skies at Hockenheim, a Formula Two race was on the programme.

It was a brooding circuit, the track disappearing from spectators' view into the darkness of the forest where it was canopied by trees. In the rain, water dripped from the dense foliage, and mist would often hang in the air. Spray was a critical problem, and the circuit had a justified reputation for treachery. At 6770 metres, with few bends, drivers were on full throttle for more than a minute at a time.

Tailgating a rival whom you could barely see, at 170mph, while not wearing a seat belt, must have been terrifying even for a driver as sublimely skilled as Jim Clark.

The Loretto-educated Border farmer had two main sponsors: Ford and Lotus. Ford wanted Clark to drive their new V8 F3L at Brands Hatch, in a round of the World Sportscar Championship. It was a much more prestigious and important event than a round of the European F2 championship on a little-known German circuit which had yet to stage a Grand Prix. However, a contractual obligation involving Colin Chapman's Lotus team and Firestone decreed that the two-time World Formula One champion would compete at the Hockenheimring for the first time.

He spun in practice, and told compatriot Graham Hill that he considered the circuit dangerous, and that he hated it.

His prescience proved fatally accurate. The man whom some still regard as the greatest driver of all time lost control of his Lotus Cosworth on a seemingly innocuous right-hand curve. It somersaulted several times, plunged into the West Schwetzinger Hardt, and into a tree. Wreckage was strewn over 300 yards. The man whom Time magazine had described as "the most famous Scot since Robert Burns" died at the scene, the ninth of 27 men to die on the circuit.

He had been travelling at almost 170mph, and only a white-faced marshal, who narrowly escaped death having been standing some 10 yards from where the car left the track, saw it happen. He described the Lotus skidding from lock to lock with Clark wrestling for control. "It went skidding and somersaulting across the grass and hit a tree with a tremendous thump. The car seemed to be in a thousand pieces."

The eight-inch trunk ripped off the spaceframe, depositing the engine and gearbox ten yards from what was left of the vehicle which partially wrapped around the tree. The rear suspension was also ripped off. Clark's skull was fractured and his neck broken.

He had been having problems with his machine, lying only eighth when on his fifth lap. Drivers behind him ventured after the Lotus veered off, that it looked like "something mechanical."

Chris Lambert, who finished fourth and had been waved through by Clark, later commented: "He must have known there was something not right with the car. He wouldn’t normally do that."

Lambert himself died four months later at Zandfoort.

We are prompted to remember Clark because the Hockenheimring has been trumpeting that the German Grand Prix is to return there next year. They made no acknowledgement of the fact that it will be the fiftieth anniversary of Clark's death. We repeatedly asked the German organisers this week whether they had any plans to mark the occasion. They declined to reply, despite the fact that the track is happy to trade on his name.

"The Jim Clark Revival" a historic car meeting, is being advertised on their website. Weekend passes cost 45 euros. They do this annually, but thus far have not contribution to the £1.65m which enthusiasts have struggled to raise for a museum in Duns, in Clark's honour.

"They have not contributed, and we haven't asked them," said Doug Niven, the driver's cousin and a trustee of the Jim Clark Trust.

With crowdfunding, a recent lottery grant of £635,000, public donations, and substantial input from Borders Council, the existing museum in Duns will be upgraded, confirms Niven. "But it won't be completed until about a year after the fiftieth anniversary of Jim's death."

Clark took the world title in 1963 and 65. Only mechanical failure in the last race of the 1962 season and the final lap in 1964 denied him further titles. His 34.25% victory average (25 wins in 73 entries and 33 poles in 72 starts) is still the highest of any driver in the all-time top-10 of total wins. In his era there were far fewer GPs. Michael Schumacher drove 308 at an average of 29.55%, and Lewis Hamilton is on 29.90% after 204 races.

Clark was the first non-American to win the Indy 500, and was second twice. Lotus could win more money in this single race than the entire Grand Prix season, but Clark himself was unimpressed by Indianapolis: "It would be fine without the Americans."

Speculation on the cause of the fatal crash never subsides. Foresters' children running across the track is one possibility which was dismissed. The RAC investigation found no evidence of pre-impact structural failure.

The senior Farnborough engineer investigating military aircraft crashes found an odd-shaped cut in one tyre which would not re-inflate having come off the rim. But he concluded the tyre was still on the rime when the car left the track.

The Armco already in use at Monaco would almost certainly have saved Clark's life, and Jackie Stewart, his friend and Scottish rival opined that had Clark been wearing a full harness, he might have survived. The Dumbarton driver who thrice became world champion, and surpassed Clark's record 27 GP victories, became a committed campaigner for driver safety. Fourteen drivers have died in F1 races, practice, or qualifying, since Clark's death, but just one since Ayrton Senna at Imola in 1994.