How many extra daily trains would be able to access London, if the GC "London Extension" still existed?

Question

How many extra daily trains would be able to access London, if the GC "London Extension" still existed?

Answer 1

If the 'London Extension' still existed then Network Rail would have a useful fourth connection between the Capital, the Midlands and the North with several expresses a day each way and an intensive local and suburban service, both of which Marylebone had before the line was truncated north of Aylesbury.

More than that, however, they would have had a ready-made line built to a standard capable of taking Continental trains from across the Channel, because by 1899 when the London Extension was built, trial bores for the Channel Tunnel had already begun and the Directors foresaw a time when cross-Channel trains from the Tunnel would be a reality.

By the time plans were in hand for the present Channel Tunnel however, the GCR Main Line had been been closed, just one victim of the 'Beeching Axe'.

Answer 2

Very difficult to answer this question.

With modern signalling, each track can accomodate a train every ninety seconds, which is 40 trains per hour.

But line-capacity is only part of the problem. Each stop made by a train reduces line capacity, and, even the most intense service can rarely achieve more than 30 trains per hour.

But capacity is radically reduced when it comes to terminals. If the terminal had just two platforms, it almost impossible to achieve 20 trains per hour. But whereas additional platforms increase the terminal-capacity, the additonal weaving movements at the approach junctions reduces the line-capacity.

Not simple.

Sorry

Answer 3

Very few I would guess, as Chiltern Railways runs a very intensive service on both the Met/GC Joint and on the GW/GC Joint. Of course, seeing as how they have extended services on the latter to Birmingham and beyond, they might  have run services to Rugby/Leicester/Nottingham on the former had it still existed...we can but dream and think what might have been...

Later: The answer mentioning terminal capacity is interesting. Chiltern Trains have had to extend Marylebone just to cope with its existing services.

Answer 4

An interesting question with no easy answer. The line would have been more easily adapted to 125MPH running then the West Coast Main Line, which has had a lot of money to achieve this. The London Extension was much better enginered then the WCML with less curves, howether Marlebone station is not the best placed station in London for comuteing as only 1 tube line conects to it. Marlebone station was also never built with as many platforms as were envisaged by the lines planners, the spare land has now been sold of to developers. What the London Extension would be usefull for is provideing extra fraight train routes as the WCML is often said to be approaching full capacity