HELENSBURGH'S MSP has urged Scotland's transport secretary to tackle capacity issues on the town's rail service.

Jackie Baillie pressed Michael Matheson on the issue at the Scottish Parliament following repeated examples of trains on the Helensburgh-Edinburgh line being operated with three carriages, rather than the six usually provided by ScotRail.

In an exchange prompted by a question from Green MSP Mark Ruskell on how commuters' views shape ScotRail timetable changes, Ms Baillie referred to promises made to provide six-coach trains on the Balloch-Airdrie route when the timetable last changed in December, in addition to the six-coach trains usually scheduled to operate to and from Helensburgh Central.

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Ms Baillie said: "As part of the timetable changes, my area was promised that there would be six-carriage trains, particularly at rush hour.

"However, in the months since, commuters have experienced short-form services, with three carriages appearing instead of six and passengers crammed in like sardines.

"I know that there is no limit on the number of passengers that ScotRail tries to squeeze on to its trains, but is there anything in the ScotRail contract about the capacity of the service?"

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Mr Matheson replied: "The member will be aware that we are making significant investment in upgrading the rolling stock in the ScotRail franchise, as a result of which 70 new Hitachi trains are being introduced on to the network to provide an overall 23 per cent increase in seating capacity.

"Part of the challenge on some routes has been the late delivery and supply of those trains and, indeed, the refurbished high-speed trains, and that is having an impact on cascading the rest of the rolling stock across the network.

"Once the additional rolling stock is in place, we will be able to maximise the use of the rolling stock to address those areas where I recognise there is congestion and overcrowding on some trains.

"The situation is unacceptable, and it is addressed in the franchise.

"However, in order to address those matters, we need to get the additional rolling stock in place, and that will be taken forward in the months ahead when Hitachi supplies the rest of the trains, which were due to have been provided by now."

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The new Hitachi trains Mr Matheson mentioned in his answer will not, however, see service on either the Helensburgh or Balloch routes; their introduction on a variety of other routes in central Scotland and Strathclyde will allow older trains to be scrapped or transferred to other operators.