Publicly owned rail is popular. But is it making the trains run on time?

The early afternoon of Wednesday 6 August was an unremarkable one on the rail network. Then suddenly, shortly before 14:00, a power failure brought trains across the north-west of England to a halt.

Chaos ensued: passengers told the BBC they were stranded on platforms for hours, with some having to book hotels for the night.

This incident, stemming from a short power cut that affected Network Rail's operating centre in Manchester, was, in itself, unusual. But it added to a difficult summer for train passengers.