44 North
Senior Member
especially longer term as eventual extensions are unlikely to be tunnelled much if at all.
The OL is still quite expensive, but a northern extension could likely be done very, very affordably as it can be elevated.
Longer term is a point in favour of third rail. Think about it. When planning future extensions/branches in an urban realm we want a line that can be nimble - i.e allow for planning of grade changes and tight turns with ease. Flyunders and flyovers, short tunnels, deviations from road ROW to rail ROW to greenspace etc... pantos will make that more difficult. Why? Because the train's profile is that much bigger. Infrastructure has to be more expansive to allow this. This is one reason I've been an advocate of ~2.75m wide train for RL rolling stock, with a commensurate longer train to compensate for the narrowness. Now with pantos we're effectively getting bigger trains.