British Rail Class 332

The British Rail Class 332 is the type of electric multiple unit train used on the Heathrow Express between London Paddington station and Heathrow Airport. The fleet was built in 1997-1998 by Siemens and CAF at the latter’s factory in Zaragoza, Spain. There are 14 four/five carriage units.

The units are equipped with Automatic Train Protection (ATP), one of the few in the UK to do so. This is largely as a consequence of the Paddington-Heathrow route operating (for the most part) on the Great Western Main Line, which had been equipped with ATP in the early 1990s as part of an experimental trial of the system by British Rail.

The Class 332 units were the first electric trains to operate over the Great Western Main Line out of Paddington when the line was electrified as far as Airport Junction. Initially, all 14 units were constructed as four-car sets but, in 2002, five units were lengthened to five cars, allowing trains of up to nine car length to be operated.

The service frequency between London Paddington and Heathrow Airport, Terminal Five is four trains per an hour (4 TPH), which is one every 15 minutes. The Class 332 can either work on their own or in pairs when in service.

The units are divided into first class and standard class accommodation - the four car sets can accommodate up to 175 standard class passengers, with up to 239 accommodated in the five car sets. First class accommodation is located in one of the driving cars - these have two different layouts, with 332002 and 332004, together with all of the five car sets able to accommodate up to 26 first class passengers, while in the rest of the four car sets up to 14 first class passengers can be accommodated. This is due to the amount of bonded luggage space provided for first class passengers in different units.

One driving car in each set is usually given an all-over advertising livery; currently RBS is providing this advertising.

Class 332 units are capable of working in multiple only with each other and with the related Class 333 units operated by Northern Rail.