ONE of the vehicles in a new Caledonian Sleeper train is reported to have emergency windows that cannot be opened.

Serco, which owns the franchise, has attributed the problem with the high-tech windows to a ‘circuit fault’, but added that ‘guest and staff safety is always our number one priority’.

The windows are designed to be a last-resort method of leaving the train in an emergency, if the compartment doors leading to the corridor cannot be opened, or if the corridor itself is blocked.

One internal source told The Scotsman: ‘It’s a bit alarming to know that should there be an emergency, escape would have been delayed because of locked exits, and, depending on the emergency, could pose a real risk.’

The Office of Rail and Road is aware, and a spokesman said: ‘Should evacuation be necessary, the primary route is via the doors. In an extreme situation, such as the vehicle being on its side, windows can be used.

‘Normally, windows are secured but not locked, and have sensors to notify the train manager if they are open.

‘On rare occasions, a false signal may be sent and the train manager is required to assesses the situation and may need to lock the window. Windows are secured to prevent an open window fouling the path of trains on adjacent lines.’

The RMT said it was consulting with its local reps in Scotland over the implications of the fault.

Caledonian Sleeper has had an uncertain few months since its new CAF Mk5 coaches entered service on 28 April last year. Faults have included wheel flats and an overrun at Edinburgh of 650m because a brake valve was closed. There have also been problems with internal plumbing, while on at least one occasion passengers had to leave the train in the middle of the night and use other services to continue their journeys.

The launch of Highlander services was delayed by several months, and Transport Scotland last year threatened to fine Serco for franchise breaches,

Complaints about the service have tripled. It was revealed last week that the number of complaints rose by 221 per cent between July and September last year, which is the peak summer season for tourist travel to Scotland, with 394 complaints for each 100,000 journeys. This was the highest figure for any franchised train operator.

Caledonian Sleeper managing director Ryan Flaherty said: ‘We recognise during the period where our new trains were introduced there was some disruption. We have taken this feedback on board and are already seeing an improvement … with less disruption as a result, and are now on track to return to our normal level of high satisfaction.’

Responding to the latest relevations about the emergency windows, he said: ‘Clear processes and standards exists to assess and manage any risks so the safety of our guests and staff is not compromised. The emergency windows have been designed, approved and risk assessed and if there is a fault with a window they can be locked until the problem is resolved.

‘As you would expect, guest and staff safety is always our number one priority and the new Caledonian Sleeper fleet is fully compliant with all mandated safety standards. We would never run a service unless it is compliant.’