scope:

Introduction

In the latter half of the 1980s and then again in the late 1990s, a number of serious collisions between passenger trains and other passenger or freight trains occurred. All resulting in the loss of passengers lives. The immediate cause of all these accidents being signals irregularly passed at danger. In November 1988, the then British Railways Board took the decision to carry out network wide fitment of Automatic Train Protection (ATP), designed to absolutely prevent such collisions. Pilot schemes were completed on the Great Western and Chilterns lines.