Calls for scepticism on self-driving cars amid bus firm roll-out

The National Transportation Safety Board said in a preliminary report released on Thursday that the Uber SUV being tested in Tempe detected the woman and eventually concluding "an emergency braking manoeuvrer was needed to mitigate a collision". But the system couldn't activate the brakes, the NTSB said. It could be decades before fully autonomous vehicles are on the roads (cars where drivers never have to touch the wheel), but the intervening period - in which human driver intervention is required as a backup - could prove more dangerous. "We need a healthy level of scepticism for the ability of humans and machines to function together", said Mr Crist. Drivers are at risk of becoming complacent, and the few extra seconds it could take for a human to intervene and recover a situation could be deadly. The report also warns that connected autonomous vehicles - which use the internet to monitor and communicate with surrounding cars - are at risk of being hacked.