Driving fast on ice is a uniquely Finnish form of lunacy; it's no wonder they excel at rally driving, particularly in wintry conditions.
But even by those standard Janne Laitinen is a seriously disturbed individual; not only has he been a test driver for a leading Finnish brand of winter tyres for more than 25 years, he also goes out on the frozen sea in his Audi RS6 and sets world speed records for driving on ice.
On 9 March he went back to his favourite bit of flat ice, a 7.5km stretch of the Gulf of Bothnia near the Finnish city of Oulu, to challenge his own world ice-driving speed record of 331.61km/h, set with the same car in March 2011.
(Incidentally, he's also the holder of the world ice-driving speed record for electric cars at 252.06km/h, set in March 2012)
STREET-LEGAL AND COMMERCIALLY AVAILABLE
He was using a new type of ultra-low profile studded tyre developed by his employers - and that's important, because the Guinness Book of World Records stipulates that the tyres be street-legal and commercially available in the country where the record is set.
It also insists that the ice must be natural, and that it must not be roughened or treated with chemicals.
The car's speed is measured over a distance of one kilometre, with a flying start, and the official result, as with all speed records, is the average of one run in each direction, which must be completed within one hour.
Laitinen did indeed better his previous mark - only just - raising the bar to 335.713km/h. At that speed, pointed out his technical manager, Matti Morri, the car is covering 93 metres (very nearly the length of a football field) every second and each stud is hitting the ice 43 times a second - which puts huge strain on the tyre carcass.
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