Brand new Caledonian Sleeper carriages are out for testing on the UK rail network for the first time ahead of their introduction later this year.

The overnight Caledonian Sleeper rail service will be transformed by the introduction of the new £100m fleet which will see Serco introduce 75 new carriages in a phased transition starting this autumn.

A total of four Mark 5 carriages are out for testing this week, running on the West Highland Line from Glasgow to Arrochar & Tarbet. Testing on the West Highland Line will continue over the coming weeks before moving onto the West Coast Main Line.

Magnus Conn, Serco’s New Trains Director for Caledonian Sleeper, said: “Taking some of the new carriages out on the network for testing marks an exciting phase in our development programme. The purpose is to monitor the interaction between vehicle and track, and to check ride comfort in a variety of suspension states and speeds

“As testing progresses onto the West Coast Main Line later this month, we will be conducting a variety of tests including running at up to 110mph.”