British Rail Class 171

The Class 171 Turbostar is a type of diesel multiple unit (DMU) train built by Bombardier Transportation (previously ADtranz) at its Litchurch Lane Works in Derby, England, which is identical to the Class 170, except for the replacement of the BSI (Bergische Stahl Industrie) coupler with a Dellner coupling. This provision was made to allow emergency joining with Class 377 DC third-rail electric units. The vehicles work on the southern regions of the British railway system, operating services from London Bridge to Uckfield and from Brighton to Ashford International, these routes being unelectrified between Hurst Green and Uckfield and Ore and Ashford International, respectively.

Design


The Southern fleet is fitted with coupling devices (Dellner) different from other Turbostars, and is classified as Class 171 for this reason. The four-car units were built with the new couplers, but Class 170 two-car units were fitted at a later date, and reclassified as Class 171/7 after the modification. Three more two-car units were later acquired, but these were built from new with the new couplers.

Southern gained 170 392 from South West Trains. The coupler on this unit has also been changed to the Dellner type. The unit has been reclassified and renumbered from 170 392 to 171 730. This unit was first delivered carrying Southern livery and the number 170 727 (because SWT needed another 170 and it was cheaper to place another unit on the Southern order than place a new order). It never operated in this form and was transferred to South West Trains where it became 170 392.

These trains have electronic automated station announcements and onboard displays unlike their predecessors.

Seating
Class 171s have mainly standard-class seating plus either nine first-class seats on a two-car or 18 on a four-car; all first-class seats are reclining and have mains power sockets adjacent to the seats.

Standard-class seating includes five full-size folding seats in the area by the universal toilet on the DMOCL(W) vehicle. With these seats folded there is room for wheelchair users and bicycles. Each passenger door vestibule area also has two flip-down seats.

The fleet of sixteen units has a total of 2,890 passenger seats.

Operations
Southern (previously named South Central) acquired an initial fleet of six two-car Class 171/7 and six four-car Class 171/8 units, to replace its ageing Class 205 and Class 207 "Thumper" fleet.

The first units were introduced in 2003 on the Ashford to Hastings "Marshlink Line" (now running further to Brighton). Services on the Oxted to Uckfield branch of the Oxted Line were later also transferred to Turbostar operation. Services from London Bridge to Uckfield went over to Turbostar operation in late 2004.

The two-car Class 171/7 run the Brighton to Ashford International service via Lewes, Eastbourne and Hastings, whereas the four-car 171/8 (and remaining 171/7 two-cars) run the London Bridge to Uckfield via Oxted service. The four-car units occasionally appear on the Marshlink Line during special events such as the Rye bonfire celebrations.

Fleet details
Formation of 2-Car Class 171/7: DMOCL(W) + DMOSL Formation of 4-Car Class 171/8: DMOCL(W) + MOS + MOS + DMOCL