Seven days . . . Had the points and the signals been designed so that the road could not be set for the commuter train's movement unless the signal for the express was red then the accident might have been avoided. Despite missing the red signal, the commuter train would have carried on along the same track, perhaps providing the driver with vital seconds in which to realise the error. In the days of semaphore signalling, practice which had been established over many years of experience ensured interlocking between points and signals. This was so designed that a signalman could not set up a conflicting movement such as appears to have been the case at Paddington. was working correctly and that the Great Western Trains IC 125 approaching London was running under green signals.
Reports suggest that the commuter train passed two yellow lights and then the red light.
It has been passed while at red on eight occasions in the last 6 years. They say that the signal is badly sited and not easily visible to drivers due to other equipment on the lineside. This comes amid a rising controversy over the implementation of an effective automatic train control system. This system warns a driver if a danger signal is overun and is able to stop the train if the driver doesn't take action. This system, known as TPWS has been developed by Railtrack and is able to stop a train that has passed a red signal.