. Chunnel is already built, but did nobody think of asking about the future of LHR before the plans were drawn up? Did nobody think of making a 5km diversion in the line to the N.E. (as it crosses the Thames), just in case?
Silver,
Infra is built based on policy at the time, diverting HS1 east on the off-chance the govt would ressurrect a long-since dismissed idea would be ridiculous extra expense, and even with this new airport, Eurostar would not want to divert their services through it, as that would lose the very advantage they have of being quicker than flying in the first place!
HS1 opened in two phases - 2003, then 2007. The design phases was long before the 2003 White Paper, which proposed, and then dismissed an airport at Cliffe, very near to the Foster proposal.
.. CrossRail stops some 10km short of the Isle of Grain (the Silver-Foster proposal) - so are they planning for a possible extension of the CrossRail line, just in case? And if not, why not?
Crossrail doesn't even go as far as Reading, a major interchange point in all directions! Why would they build out to a fantasy airport project long before its proposed opening date?
and a couple of km short of the Chunnel link
It would appear logical to have a junction between Crossrail and HS1 at Ebbsfleet, but that station doesn't even link with the nearby conventional line just round the corner.
Which goes part of the way towards explaining why it, combined with Stratford Int, is such a White Elephant/
Meanwhile HS2 is going its merry own way and does not link with Heathrow, CrossRail, Chunnel, and nor with Silver-Boris !! Just what is the point of HS2??
Silver, I suggest you do a bit more reading on the HS2 plans before dismissing it completely.
HS2 and Crossrail will meet at Old Oak Common - and from there, HS2 passengers can transfer to LHR. However, there is no guarantee they will be able to make a single transfer to T5 - unless the LHR express also stops there, or is integrated into Crossrail. As with Ebbsfleet, a number of other lines pass by - North London, Central tube line, Bakerloo too - which would enable a sizeable London West interchange, but the beancounters have sadly left these out.
There is a thread about HS2 in Jetblast, where I have made many criticisms, including the suggestion that if they are serious about BI - or a second runway at STN as the cheapy option - Euston needs to rotate 90deg quicksmart!
Are the dimensions, guages and vo(l!)tages on these lines compatible?
No. Crossrail already provides relatively few continuation benefits outside the existing TfL zones, as mentioned above. One of the reasons it is so expensive is that it uses 6m diameter twin tunnels - and this is so that it can take overhead electrification - even though 3rd rail is used throughout the south east, and may well have resulted in a much lower build cost, although the trains would have cost more.
Traditional tube tunnels are much thinner at just 3.8m - could they have done a similar job - in effect an express service running past smaller stations, just like NYC?
HS1 & 2 are built to European loading guages, which make it possible to run double-decker trains.
Afaik, all are 25KV AC. High speed trains could not run through the Crossrail line - far too many stops, and different train layout - I presume Crossrail platforms will have anti-jump barriers too, like the Jubilee line xn.
However, if BI results in a substantial demand for trains to it from west of London, could a link be provided between the HS1 line and the (by then) electrified line to Reading and beyond? I don't know the technicalities of that, nor do I know if there will be any domestic link between HS1 & 2.