Class 450

The Class 450 Desiro is a type of electric multiple unit built by Siemens Transportation between 2002 and 2006 in Germany. A total of 127 units were built, with the first entering service in October 2003.

A South Western Railway Class 450 at Barnes in 2023

Background

In April 2001, 785 vehicles were ordered by South West Trains in order to complete the replacement of its slam-door rolling stock, in accordance with its franchise commitment to do so by 2005, as the slam-door trains, many of which were more than 40 years old, did not meet modern health and safety requirements. Introduction to service was delayed by the required power supply upgrades capable of powering the new trains, which feature air conditioning, a feature not present in the slam-door trains they replaced. In the December 2004 timetable change, the Class 450 Desiro began serving most intended routes, although introduction was delayed until June 2005 in some areas. The units are leased by Angel Trains to South Western Railway.

68 new vehicles were ordered by South West Trains as a replacement to the growth order which was diverted to form the similar Class 350 range of electric multiple units.

Operations

Class 450 units operate on suburban, outer-suburban, and regional services originating from London Waterloo. They are deployed on all South Western Railway (SWR) lines with the exception of the non-electrified West of England Main Line and the Eastleigh to Romsey Line.

Occasionally, Class 450 units are used on the Portsmouth Direct Line for services between Waterloo and Portsmouth Harbour, substituting for the Class 444 units originally intended for these routes. This substitution has led to complaints from some passengers due to the Class 450's higher-density 2+3 seating arrangement, which is perceived as less comfortable.

Maintenance and Modifications

Both Class 444 and Class 450 fleets are serviced at the Northam Traincare Facility in Southampton. This facility is equipped to handle preventative and corrective maintenance, deep-cleaning, and overhauls for up to eight units simultaneously.

In March 2012, the Class 450 fleet, along with the Class 458 and 444 fleets, was upgraded with regenerative braking technology.

Class 450/2 and Further Orders

Initially, South West Trains (SWT) ordered 100 four-car Class 450/0 sets and 32 five-car sets intended as Class 450/2 for inner-suburban services. However, due to disagreements with the Strategic Rail Authority regarding infrastructure changes, the order for the 32 five-car sets was cancelled. The 160 vehicles were redistributed, with an additional 10 four-car sets added to the SWT order and the remaining 120 vehicles ordered as 30 four-car sets of the dual-voltage Class 350 for Silverlink and Central Trains.

Subsequently, SWT received an additional 17 four-car sets, bringing the total number of Class 450 units to 127. These units were delivered in 2006, shortly after the final delivery of the initial order. Unit 450101 was damaged in Belgium and required repairs at Siemens' Wildenrath facility, delaying its entry into the UK.

Class 450/5 Modifications

In January 2008, 28 Class 450/0 sets were reconfigured and renumbered as Class 450/5, designated for services between Waterloo and Windsor, the Hounslow Loop Line, and Waterloo and Weybridge. These units had their first-class seating removed and replaced with standard-class 2+3 seating. Additional seats were removed to increase standing capacity, and extra handrails were installed. The modified units, originally numbered 450043 to 450070, were renumbered to 450543 to 450570 and marked with "HC" (denoting 'High Capacity') on the front. The modifications were completed at the Bournemouth Traincare Depot.

Following the modifications of Class 458/5 for Windsor Lines, the Class 450/5 units had their first-class seating reinstated and began operating across the SWR routes. Although they retained their 4505xx numbers due to their distinct seating configuration, they were returned to their original numbers after completing their interior refurbishment in late 2019.

Refresh

As part of its franchise renewal in 2017, South Western Railway undertook a comprehensive refurbishment program for its Class 450 fleet. This refurbishment included deep cleaning of every unit, replacement of carpets and seat covers, and the installation of plug sockets in every two standard-class seats.

The refurbishment also involved modifications to the seating arrangements. The 24 first-class seats located in the center of one of the intermediate trailers were replaced with additional standard-class rows. New first-class areas, each featuring eight leather seats and tables with wireless charging facilities, were installed adjacent to each driver's cab.

Additionally, the subclass /5 high-capacity units underwent similar refurbishment and were returned to their original numbering. Consequently, all Class 450 units now share a unified layout.

Accidents & Incidents

On 6 November 2017, unit 450025 was derailed near Wimbledon. The incident resulted in four injuries and the evacuation of over 300 passengers. The derailment was caused by track spread—a widening of the gap between the rails—on a 120-meter stretch of track that had not been inspected or maintained for many years due to a misunderstanding between Network Rail and London Underground regarding maintenance responsibilities.

On 4 March 2024, unit 450092 was involved in a derailment between Woking and Surbiton stations after striking an obstruction on the track while traveling at 90 miles per hour (140 km/h). Fortunately, no injuries were reported, and the train was evacuated safely.