Or taking into account limitations due to track layout, order a small number of 8 coach units primarily for routes from Victoria, then split the rest between 10 & 12 coach units.
Ordering the 10 coach units mainly for Charing Cross which has limitations on which platforms 12 coach units can use.
Majority of services from Cannon Street will be 12 coaches, if all the platforms can support such long trains.
The trouble with ordering several different cariage lengths is that it makes planning formations more difficult as you need the correct units in the correct places at the correct time.
I shall have a look at the sectional appendix to find out more and see what sort of formations would be the best overall options.
The following routes can run a 12 car 465 down them.
Class 465 12-car Networker trains MUST ONLY be formed of 3 x 4 car units coupled together, and MUST NOT include any Class 466 units.
The following routes are permitted for Class 465 Networker 12-car operations:
Charing Cross/Cannon Street and Sevenoaks, Dartford, Gravesend and Hayes
It looks like a fixed 12 car unit on SE metro could present quite a few issues, see below for where 12 car 465s can't run.
These routes cannot have a 12 car 465 down them
The following routes are not permitted for Class 465 Networker 12-car operations:
• All routes out of Victoria or Blackfriars
• Any station via Herne Hill or Catford
• Bromley North Branch
• New Beckenham spur to either Petts Wood Junction or Sevenoaks via Bromley South
• Woolwich Dockyard station platforms are not long enough to accommodate a 12-car formation and therefore no 12-car Networker
formations are permitted to call at this station in either direction
• Down Fast Platform 3 at Grove Park has no 12-car equipment, therefore no Class 465 12-car Networker formations are permitted to call at this platform.
The following sidings are not permitted for Class 465 Networker 12-car operations:
• Dartford Up and Down sidings (Note: With the exception of Number 1 road at Dartford Up sidings which can accommodate a 12-car train)
• Slade Green Up sidings
• Plumstead sidings (Note: Number 1 road at Plumstead can accommodate a 12-car train but a shunter is required)
• Shunting of 12-car trains BETWEEN the up and down sidings at Grove Park is not permitted due to signal sighting issues with L1299 signal (Country end of platform 3 at Hither Green station).
The following instructions apply to Class 465 Networker 12-car operations at Charing Cross Station:
• Platforms 1, 2 or 3 shall be used for the operation of Class 465 Networker 12-car formations. Kent / Sussex / Wessex Routes Sectional
• Platforms 4, 5 or 6 are not long enough for a Class 465 Networker 12-car formation to be accommodated. Therefore no Class 465 Networker 12-car formation in passenger service should be routed into platforms 4, 5, and 6 under normal timetable and train regulation conditions.
• All Class 465 Networker 12-car formations will normally be routed on the Up & Down Charing Cross Slow Lines from Ewer Street Junction. Drivers are required to contact the signaller if a route leading to Platforms 4, 5 or 6 is set for a Class 465 Networker 12-car formation;
• If during planned degraded and emergency working, a Class 465 Networker 12-car formation needs to be routed into these platforms, then the train must have the last 2 coaches locked out of passenger service at Waterloo East.
• If a Class 465 Networker 12-car train is inadvertently routed in Platforms 4, 5 or 6 at Charing Cross, due to infrastructure or train failure or due to the error of signaller or/and the driver, the driver must, on the train coming to a stand, not release the doors and carry out the following actions: a. An announcement must be made to all passengers that the train is not fully berthed in the platform and that there will be a delay in opening the doors. b. The driver, assisted if necessary by platform staff, must walk along the train and then open each coach individually by the external local door release. c. The passengers in the last two coaches must be verbally advised to walk through the train so they can safely alight from a coach berthed in the platform.
overall, a fixed new 240m 12 car unit would cause headaches.