RED FACED engineers were last week left scratching their heads after a demonstration of a 'passively safe' road sign support left a car with a smashed windscreen and a ruptured radiator.
A demonstration of the Lattix aluminium pole at Santa Pod raceway, Northamptonshire, was meant to cause little damage to a Vauxhall Astra being driven into it at 100km/h.
Instead the car was a write off.
'Oh dear, that's not supposed to happen, ' said Mott MacDonald head of traffic management Andy Pledge as the car hit the aluminium pole with an almighty crash.
Three bolts at the pole's base were supposed to shear on impact, but one failed to do so.
But the demonstration still impressed Highways Agency offi ls because the stunt driver walked away from the test unharmed.
Earlier a remote controlled car was smashed into a conventional steel pole road sign support at the same speed. It fl ped over and suffered serious damage to its front end and windscreen.
'I know which car I would rather be in, ' said Highways Agency technical adviser for standards Jim Gallagher.
'It's not what I expected but he [the stunt driver] was going at 100km/h and walked away, so it's encouraging, ' he added.
The Lattix aluminium masts have so far been used for road signs on the A43 Towcester bypass and adopted by Cheshire County Council for signs throughout the county.
The posts were given an official thumbs up by the Highways Agency in November 2004 when it published its advice note on passively safe signposts.
Another advice note covering the use of passively safe lighting columns and traffic lights is due to be published this November.