Class 159

The Class 159 is a class of diesel multiple unit, originally built in 1989–1992 by British Rail Engineering Limited at their Derby Litchurch Lane Works as Class 158. Before entering traffic, the original 22 units were modified at Rosyth Dockyard to Class 159 to operate services from London Waterloo to Salisbury and Exeter St Davids, replacing various locomotive-hauled passenger trains. The units were originally branded by Network SouthEast as South Western Turbo.

A South Western Railway Class 159 in 2018

History & Design

In the late 1980s, the locomotive-hauled stock on Network SouthEast's West of England route, running from London Waterloo to Salisbury, Yeovil Junction, and Exeter St Davids, urgently needed replacement. The Class 50 locomotives were ill-suited for the stop-start nature of the route and frequently experienced breakdowns. Due to the extensive single-track sections west of Salisbury, following the Beeching cuts, a single breakdown could cause significant disruption. Various solutions were considered, including electrification, shortened HSTs, the construction of new locomotives and stock (a passenger version of the proposed Class 48), or the proposed Class 171 (intended to be part of the Networker family, an intercity version of the Class 165 – not to be confused with the later Class 171 Turbostars). A study determined that the best options were either electrification or new DMUs.

With the UK economy in decline in the early 1990s, it was discovered that Regional Railways had over-ordered Class 158s, coinciding with Network SouthEast's search for a similar number of new diesel trains. NSE agreed to take on the surplus Class 158s.

The initial 22 units were built as Class 158 units but were rebuilt by Babcock Rail in Rosyth Dockyard before entering service. This rebuild included the addition of first-class accommodation, retention toilets, and various other modifications. The rebuild was necessary because Network SouthEast and the newly privatised BREL could not agree on the terms for a variation order to the NSE specification.

The first unit (159004) was delivered to NSE on 6 January 1993.

The units converted to Class 159 specification during construction are numbered 159001–159022, with individual vehicles numbered 52873–52894 and 57873–57894 for driving motor vehicles, and 58718–58739 for intermediate motor vehicles. The entire class is maintained at a purpose-built depot in Salisbury.

In 2007, eight additional Class 159 units were created by rebuilding surplus Class 158 units displaced from TransPennine Express.

The units are equipped with BSI couplers, allowing them to work in multiple not only with other units from the same class but also with Class 170 and the classes of the Pacer and Sprinter families.

Operations

The units were allocated to the West of England sector of Network South East, operating services between London Waterloo and Exeter. They also served routes between Salisbury and Southampton, and on the Reading to Basingstoke line, replacing older DEMUs. Subsequently, they were transferred to the South West Trains shadow franchise in preparation for privatisation.

When British Rail was privatised, the West of England route was transferred in 1996 to the South West Trains franchise, awarded to the Stagecoach Group. Beginning in 2000, the units were progressively refurbished and repainted from Network SouthEast’s blue, red, and white livery to South West Trains’ express livery. Other post-privatisation updates included clearer LED destination displays, improved air-conditioning, and additional openable windows.

Currently, the Class 159s operate mainly on the London Waterloo to Salisbury/Exeter route in formations of six, eight, or nine coaches (comprising either 2 × Class 159, 2 × 159 plus 1 × 158, or 3 × 159 respectively), and between Salisbury and Exeter in three- or six-coach formations. Until the December 2009 timetable change, some trains continued beyond Exeter to Paignton, Plymouth, and Penzance, usually as three-coach units, though there were occasional six-coach formations on weekends. These services are now operated by the Great Western Railway, and the service to Bristol Temple Meads is also handled by Class 159s.

Since 2006, the original Class 159 fleet of 22 has been supplemented by eight three-coach 158s (renumbered into the 159/1 series) and 11 two-coach Class 158s. The move to standardise on 158s and 159s enabled the transfer of the nine Class 170 'Turbostar' units to other operators. Eight were allocated to First TransPennine Express, while the remaining unit was given to Southern for integration into the Class 171 Turbostars.

Refurbishment & Conversions

2000

South West Trains began a refurbishment programme for its 22 Class 159/0s in 2000. The seats were re-trimmed and interiors repainted. The units were repainted into SWT livery.

2008

The units received another refurbishment in 2008 at Wabtec Doncaster. CCTV and PIS (Passenger Information Systems) were installed, new seating was installed in first class and at the same time the units received a modified version of the SWT express livery (with orange doors as opposed to the red doors on Class 444 units) for compliance with disabled access regulations.

Conversions

Eight of TransPennine's surplus three-coach Class 158 units were refurbished to match SWT's existing Class 159 units at Wabtec Doncaster, and renumbered into Class 159 subclass /1. The first updated units were delivered to South West Trains in November 2006, and by May 2007 all of the new subclass were in service.

The refurbishment included making the first-class accommodation area larger and completely refitting it, brighter interior lighting with new diffusers and the plating-over of the disused toilet in the MSO vehicle. The Class 159/1s have been fitted with retention toilets. Additional alterations include the installation of a Passenger information system (PIS) and CCTV as is fitted on the 159/0s.

The converted units however retained their original Cummins NTA855-R1 engines, which produce 37 kW (50 hp) less power than the R3 variants fitted to the Class 159/0 fleet.