February 1997: At least 11 people die after a collision caused by human error and a signalling failure north of Aswan.

BBC: Egypt's history of train disasters

The theft of cables used for signalling, compounded by human error, caused the crash, said the head of South Africa's rail authority.

BBC: South Africa commuter trains collide near Pretoria

Mr Foster added statistics had found that about 95% of all road collisions were caused by human error which suggested they could and must be prevented.

BBC: Slight fall in road fatalites

Most ground accidents are caused by human error.

WSJ: Honeywell Tests Autopilots for the Tarmac

The railway companies complain that only 3% of crashes are caused by the sort of human error that PTC is designed to avert and that claims that the system will improve efficiency on the network are unfounded.

ECONOMIST: American railways

"Saturday was caused by a software problem, not a human error problem, " Wright said.

CNN: Software glitch delays London flights

The problems can be caused by power failures, inadvertent severing of telecommunications links, corrupted software, bad hardware or human error.

WSJ: Delays Hit 1,300 American Airlines Flights