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Short Form Update 11th Oct 2019

A message from the Customer Service Director

Dear Customers,

The availability of our fleet continues to be an area of focus for Chiltern Railways. We have seen improvements in the situation over the past two months, but there still remains work to do to offer you the reliable and comfortable service you deserve. 
Since the previous update the Engineering team have continued to work hard to address the ongoing fleet short form issues. A number of activities have been completed which have started to demonstrate an improved fleet availability position and this will continue to increase the number of trains we can reliably provide for service. We have: 

  • Reviewed the required scheduled maintenance to allow a greater throughput of trains at the depots 
  • Had an increased numbers of Engineering staff available to rectify defects and undertake scheduled maintenance 
  • Worked closely with our suppliers to improve the delivery of key materials and to de-risk further material shortages 
  • Worked closely with train owners to develop toilet repair processes and improve material supplies 
  • Introduced alternative tyre turning facilities at external sites 

We now more regularly output the correct number of certain train types, but we are still reliant on the completion of several activities before we can confidently output the correct amount of all trains. These are: 

  •  The completion of repairs to a long term stopped train following a derailment – Expected completion date 13th November 
  • The completion of the modifications to our Silver Set trains in order that they comply with accessibility regulations – Expected completion by December 

The completion of these two activities will effectively allow the release of two additional trains, which will allow a more consistent train service delivery. 

Please accept our apologies for the lack of capacity over recent months, we will continue to keep you updated on the situation as we work to resolve it.


Alan Riley

Customer Services Director, Chiltern Railways



22nd August 2019


Dear Customers,

Please accept my apologies for the ongoing disruption caused by trains needing maintenance. I know how frustrating it is when your train turns up and it’s shorter than normal. We recognise that this has caused uncomfortable journeys for customers who have been unable to get seats or not board their service at all. Clearly, this isn’t the service you have come to expect from Chiltern with our industry leading performance and passenger satisfaction scores. Here I have tried to explain why your trains have recently been shorter than normal.

What has gone wrong?

Recently we have been unable to provide the required number of carriages each day to run trains of the lengths intended in our timetable. When this happens, we are forced to make decisions on which services will be shorter than planned in order to minimise disruption for the whole route. This has led to overcrowding on certain services and uncertainty for our customers as to what kind of journey they can expect.

A train that is shorter than usual is called a “short form”. Our commuter trains are made up of one or two shorter trains coupled together to make one long train. If we are unable to couple together the usual amount of trains, we end up with a shorter train than usual. Unfortunately, this means there are fewer seats than usual, which makes peak time trains overcrowded – we are very sorry for the inconvenience this causes.

What causes a short form?

A short form is usually because a train or carriage is out of action. This might be due to a fault or due to damage, or it might be because the train is undergoing one of its routine service checks. There are very strict safety guidelines for train maintenance, which is one of the reasons why the UK’s railways are the safest in Europe.

Why has this happened?

There is no one cause of this situation, but rather several different factors which have come together in the last few months. Chiltern Railways has a variety of train types which have been acquired over the length of our 20-year franchise. Over the years we have provided new services and increased the lengths of trains in response to customer demand. This has put a strain on our fleet as only a very small number of carriages are able to be stopped at any one time for maintenance without impacting the service you receive.

Many of our trains are nearly 30 years old and we have had problems getting parts as suppliers reduce their support in manufacturing new components, particularly around ageing electronic control systems. Another factor is the large number of Wembley events which have reduced the time available for maintenance and repairs to take place and an unforeseen level of wheelset damage which requires the trains to be removed from service until the wheels can be changed or repaired.

Additionally, new legislation is due to come into effect at the end of the year regarding accessibility requirements for trains. This means that our Silver Sets are being sent away, one at a time, for modifications to comply with these standards and this has placed further demand on the fleet.  In addition, we have had a number of trains stopped for long term repairs after specific incidents including one train which was derailed and damaged at our depot.

What are we doing about it?

Our engineering and performance teams are working hard to stabilise the position and get back to the point where we can offer the full number of carriages to our customers. We now have a three-month action plan to define the steps we are going to take to address the situation and will be sharing these with the Chiltern Passenger Board. These include:

  • Starting a programme to overhaul the electrical power systems on our Class 165 trains which have proven unreliable in recent times, particularly during the hot weather.
  • Changing our approach to heavy maintenance to optimise the amount of time this takes on each train.
  • Reviewing our processes for how we maintain our trains' wheels in an effort to reduce the current high levels of damage seen.
  • A review of the required staffing levels at our depots and ensuring optimised working processes.
  • Working with our supply chain to build up stock levels of critical components
  • Continuing to seek out all suitable additional rolling stock.

How can I find out if my train is shorter than usual before I arrive at the station?

We publish information about which trains are shorter than normal on JourneyCheck. You can sign up for automatic alerts to your inbox via

What are our longer-term plans?

Whilst we would like to be in the position of leasing new trains this is unlikely to happen before the end of the current franchise in 2021. There is a national shortage of diesel rolling stock which would be appropriate to run on the Chiltern lines. Even when some does become available, there is a preference from the Rolling Stock Companies who own these trains to lease them to new franchises with longer contracts in place. Instead we are looking at a range of options including standardising the lengths of some types of trains to free up extra seats during the morning and evening peaks, and exploring the expansion of one of our depots to increase our maintenance capacity.

Please be reassured that we are working hard to get the fleet back to the position where we can consistently provide the number of seats required. Thank you for your patience and for bearing with us whilst we implement this plan.

Alan Riley

Customer Services Director, Chiltern Railways