Marples and Beeching

That would seem unlikely given Berne gauge wasn't agreed until 13 years after it was built!

 

Just not true I'm afraid. The myth seems to date back to a writer in the 1960s who has been widely repeated. The London extension was built to the then current GC gauge, which was one of the larger pre group gauges and a bit taller than current Network Rail basic gauges, but way smaller than the Berne gauge, which in any case wouldn't appear for at least another ten years. In the drawing below the gray shadow is Network Rail W6A. The original drawings all exist, and of course the current GC maintain a good number of the structures, so there is not a shadow of doubt.

 

Incorrect see https://railnews.mobi/news/2020/04/20-monday-essay-could-the-great.html which states
"GCR’s dimensions were smaller than those of the future Berne Gauge. The Berne loading gauge width is usually accepted to be 3.15m, while the Great Central was built to a width of 2.82m. The Berne Gauge maximum height was 4.28m, while the GCR equivalent was 4.09m".

 

The island platforms of the GCR line were built so that the track could be slewed further away from the platform to increase the loading gauge and even add in extra tracks. There is a very good video here which shows what is left of the line and the tremendous asset that was just squandered. With the exception of Nottingham Victoria is not as if much has even been done with the land since.

 

Indeed they were. But those clearances were with 1890s speeds in mind, not the vastly different speeds of HS trains, and the air pressures and drafts they generate.


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The main disadvantage of using the GC for HS2 is that it goes nowhere near Birmingham.

 

I'd have thought going nowhere near Birmingham should be considered a distinct advantage ...

Tom

 

The loading gauge is irrelevant, because the trains for HS2 will need to run on some sections of existing lines. And as for island platforms; if the GC had survived long enough to be converted to HS2 the smaller stations would have been closed anyway.

 

the smaller stations were closed in the early 60s anyway - Braunston and Willoughby (from memory) actually in the late 1950s!

 

That's actually incorrect on loading gauge - HS2 will be built to a continental loading gauge, although some (possibly all given recent paring back of the scheme) trains will be built to UK loading gauge. I believe this means that there will need to be separate "captive" and "interoperable" platforms to accommodate this.

As for the island platforms, that may be true of the likes of Finmere, but the point remains that HS running requires significantly greater separation between bystanders and trains than the GC pattern provided. For a thought experiment, imagine standing at Loughborough and the spacing that a non-stop HS2 train would require.

 

on the latter bit (specifically curvature) I don't think it does remain moot - either the government, HS2 or somebody else (there're so many documents on this subject that I forget which it was) specifically looked at the GC route to see if it could be the basis of HS2. AIUI, where it can, it does, but even in the wide open countryside around Helmdon/Culworth/Woodford the curves were too tight to take high speed running. Living where I do, you can see the bits of the formation that are being used, and where the old formation swings away/back underneath again.

It really isn't being built from scratch for fun (not saying you're saying it is but for the benefit of other readers) - HS2 really did look into whether they could plug and play on the old GC route and mostly they can't - and not just because it has been built on. Where it makes sense to use the GC, HS2 does - see Finmere.

 

And the main disadvantage of Maglev is that you can't have junctions (can you?). One of the stories of the planning of HS2 over the last twenty years is that it has gone from a free standing line, possibly competitive with the classic network, with minimal interfaces, and therefore ultra reliable and bespoke trains, across to a line with high connectivity to the classic system at Birmingham Int, Water Orton, Lichfield, Crewe, Trent, Manchester Airport etc. To get the frequency and traffic density you have to combine the traffics. Once you decide that, the GC route is really a non-starter.

 

But that only highlights the "chicken and egg" situation of the timetabling. How far did the timetable reflect the poor numbers of travellers or how far did it cause the poor number of travellers. Certainly it initially offered competition for the LMS on its Sheffield / Chesterfield / Nottingham / Leicester to London services but it also provided those centres to connections with Rugby, Banbury and the GWR main line - even to the South West by avoiding Birmingham with Oxford. In many ways the GC line could have provided the freight line that frees up both the Midland Main Line and West Coast Main Lines for passenger traffic but that option was denied once by-passes covered some lengths of the GC after its closure.

 

But what did it offer that the LMS routes did not, that would have justified retaining that main line route as well? How much did BR actually need that capacity?

I find it revealing that the esteemed Gerard Fiennes went into print over wishing the GCR closed - not a BR manager who just believed in closing things down.

 

Only once on board!

In view of info provided (cheers folks), I do accept whatever I recalled about the GC loading gauge is evidently complete crap wide of the mark. Whether that's just my memory playing tricks, believing a long forgotten dodgy source, or a little of each is immaterial, The comment concerning platform edges from @toplight (lovely video btw) seems indicative of some thought having been given to a possible increase in the operating envelope, but like the route itself, a sadly over optimistic provision.

 

Banbury is a good part of the way, with a continuation to Manchester .

if the GC still lived i would be wanting to close the route to regular traffic and engineer the whole lot to HS standard . Marylebone -Banbury-Manchester/Birmingham..

at least you would save the cost of maybe 3/4 of land acquisition and not annoy a lot of Tory voters

 

Looking over my back fence at Culworth Junction... you're aware Banbury wasn't on the route? It was at the end of a south facing spur from just south of Woodford Halse and sits 8.5 miles to the west of the GC mainline. So to take in Banbury would be challenging/expensive to say the least.

That's before we get into a high speed London - Manchester route that goes via Sheffield, and (presumably) sees 200MPH trains over the Woodhead route...

 

I'm not sure the GC was built with the radius curves required for HS2. I really doubt you would save that much doing that. As to your last 7 words, I'm not sure if that is a good or bad thing

 

It absolutely wasn't. Once more for the hard of reading. You can see which bits of the GC route south of Rugby were suitable for HS2 (never mind the bits that have been built over) because they're being used. The volume of (south of Rugby) new formation is indicative of which bits aren't.

 

The only bit of the GC formation being used for HS2 is from Calvert up to Mixbury, isn't it? Not very much at all!