| British Rail Class 717 Desiro City | |
|---|---|
 Great Northern Class 717 unit atPalmers Green | |
 The standard-class interior of a Class 717 unit | |
| In service | 28 September 2018 – present |
| Manufacturer | Siemens Mobility |
| Built at | Krefeld,Germany |
| Family name | Desiro City |
| Replaced | Class 313 |
| Constructed | 2018 |
| Number built | 25 |
| Formation | |
| Fleet numbers | 717001–717025 |
| Capacity | 362 seats |
| Owners | Rock Rail[1] |
| Operators | Great Northern |
| Depots | Hornsey (London) |
| Lines served | |
| Specifications | |
| Car body construction | Aluminium[2] |
| Train length | 121.7 m (399 ft 3 in) |
| Car length | 20.2 m (66 ft) |
| Width | 2.80 m (9 ft 2 in) |
| Floor height | 1.10 m (3 ft 7 in) |
| Doors | Double-leaf pocket sliding,each 1,500 mm (59 in) wide(2 per side per car) |
| Wheel diameter | 820–760 mm (32.28–29.92 in)(new–worn)[3] |
| Wheelbase |
|
| Maximum speed | 85 mph (137 km/h) |
| Weight | 204 t (201 LT; 225 ST) |
| Axle load |
|
| Traction system | SiemensIGBT |
| Power output | 1,200 kW (1,600 hp) at wheels |
| Acceleration | 0.85 m/s2 (1.9 mph/s) |
| Electric system(s) | |
| Current collector(s) |
|
| UIC classification |
|
| Bogies | Siemens SGP SF7000[4] |
| Minimum turning radius | 120 m (390 ft)[3] |
| Braking system(s) | Electro-pneumatic (disc)andregenerative |
| Safety system(s) | |
| Coupling system | Dellner |
| Track gauge | 1,435 mm (4 ft 8+1⁄2 in)standard gauge |
| Notes/references | |
| Sourced from[8] unless otherwise noted. | |
TheBritish Rail Class 717Desiro City[9] is anelectric multiple unit passenger train built bySiemens Mobility, currently operated byGovia Thameslink Railway on itsGreat Northern Hertford Loop and Welwyn stopping routes. Built to replaceClass 313 trains on services intoMoorgate, a total of 25 six-car units began entering regular service from March 2019.[10][11] The units are similar to theClass 700s (in use withThameslink) and theClass 707s (in use withSoutheastern).
Upon winning theThameslink, Southern and Great Northern franchise,Govia Thameslink Railway (GTR) announced that it would seek to procure new trains totalling 150 vehicles to replace the then-40-year-oldClass 313 units operating on services to and fromMoorgate.[12] In December 2015, GTR announced that it had selected Siemens to provide this new fleet, originally designated Class 713,[4] as a follow-on order from the mainClass 700 order, with entry into service expected from March 2019.[13]The order was finalised in February 2016.[14][15]
A significant difference between Class 717s and the earlier Class 700s is the provision of fold-down emergency doors at both ends of each train. These are required for emergency evacuation of passengers[9] while inside the deep-levelMoorgate tunnels.[16]
Siemens began testing the Class 717 units in Germany during June 2018.[17]
The first unit operated a single preview service in late September 2018, with gradual introduction from the spring of 2019.[18] The finalClass 313 service onGreat Northern ran in September 2019, completing the fleet replacement by Class 717 units.[19]
In September 2021, the installation ofEuropean Train Control System (ETCS) on the Class 717 fleet was successfully tested on theThameslink 'core' route betweenSt Pancras International andBlackfriars stations in central London.[20] The success of the test allowedGovia Thameslink Railway to work towards enabling the use of ETCS in passenger service on theNorthern City Line in November 2023, which will be followed by the decommissioning and removal of the existing conventional signalling system in 2024.[21] Further testing and implementation on other lines and routes is planned.[22]
In October 2022, testing started for the upgrade of the ETCS baseline from B3MR1 to B3R2, with dynamic testing planned for December 2023.
Class 717 trains generate electricity throughregenerative braking.[23] The trains are also 20% lighter than their predecessors, making them more energy efficient.[24]
| Class | Operator | Qty. | Year built | Cars per unit | Unit nos. |
|---|---|---|---|---|---|
| 717 | Great Northern | 25 | 2018 | 6 | 717001–717025 |
