"Preservation does not always mean forever. Railcar M51935 would not survive another ten years."
INTRODUCTION
Once upon a time, UK railway preservation was the constant. A reassuringly stable relief from the chaotically evolving national network. But particularly since privatisation, the weight of evolution has shifted.
The national scene does still evolve, with new trains and traction displacing old. But lifespans have become much longer than they were when diesel preservation began, and a secondhand market has developed, keeping older trains and traction in service way beyond their original projected shelf lives. Based on an average British Rail shelf life as understood in the 1970s, the Class 66s would have been running the gamut of farewell tours by now. Imagine that!