Two experts from the University of Bologna made a microscopic examination of the fracture in the steering column on the car that the former world champion was driving when he died during the San Marino Grand Prix in May.
They concluded that the break was probably not caused by the car's impact on the concrete wall at the end of the Tamburello curve, but by a quality flaw, or possibly the use of too thin a metal.
Another French paper, Infomatin, quoted the Williams chief designer, Adrian Newey, as saying that the steering of Senna's car had been changed just before the Imola race because the Brazilian had complained he could not see his control panel.
'We reduced the diameter of the column,' he said. 'In Senna's accident, this trunk broke. But the telemetry data doesn't tell us if the break happened before or after he hit the wall.'
A 10 per cent possibility was that the bottom of the car had scraped the track because tyre pressure was too low.
A spokesman for Williams said: 'Current media reports regarding the possible cause of Ayrton Senna's accident are not based on the official findings of the technical experts investigating the matter. They have not yet reached any conclusions and therefore any speculation is unfounded.'
The Italian Grand Prix, called off on safety grounds, yesterday looked back on for 11 September when the government approved a revised plan, widely criticised by environmentalists in its original form, to make the Monza circuit safer by cutting down trees and widening run-off areas.Reuse content