Roger Ford is very quick to leap to the defence of the good old ECML electrification at the expense of the nasty GWML project. Fair enough, so GWML is costing nearly four times more. Perhaps Series 1 is over-engineered.
I've spoken to Roger about the ECML and whilst I appreciate his viewpoints on the ECML electrification, I think he's downright wrong. He has long suggested "too much power is just enough" and I think we've been burned far too often by not taking a similar approach to our infrastructure, including electrification.
I personally think the ECML is something akin to cutting off one of your feet to save money on your shoe bills. It works fine until you fall over and break your glasses a couple of times a year.
There's plenty of evidence that the ECML wasn't just inexpensive, but corners were cut. There are plenty of structures on the ECML that could do with new foundations and are currently subject to increased monitoring, some of these have resulted in dewirements in the past, so I'm unconvinced by Roger's arguments that the foundations on the GWML are over engineered.
HSE and ORR wouldn't allow the same methods of installation either, so you can double or treble the costs involved in the actual electrification, there's additional bridge parapet raising works needed now, 1.5m is no longer sufficient and 1.8m is the new minimum height, that will cost more money. ECML installation was cheap because BR considered it acceptable to have a man up a ladder doing work on a headspan, and that there was sufficient time between trains to install a headspan. That's things that absolutely do not apply today.
There was absolutely no future proofing in the design - it can't take the next gauge of contact wire and catenary wire upwards without significant modification, and has absolutely no capability to cope with 140mph running with multiple pantographs, something that wasn't an unrealistic possibility when the project was approved. There's also a greater difficulty in changing layouts and altering junctions because of the way contact/catenary wires are suspended from the headspans.
The GWML, when it's done, will have been done properly, it will cope with faster trains, more trains working in multiple and won't cause total chaos in the event of a single track dewirement. When it's done and we're doing the post-mortem, people will wonder quite why we were so reluctant to spend money and do things properly. As we do today with the ECML every time the line is closed to electric traction and we've got VTEC controllers lining up Class 67 locos for drags.
mr_jrt said:
...just to interject here - it's my understanding that the OHLE on the ECML is perfectly capable of handling 140mph as would have been provided by the 225s, as they only would have had a single pantograph. You need a higher tension wire for dual pantograph operation as required by units such as the IEPs, so not such the face-palm cutback as it may outwardly seem.
I don't know if it's perfectly capable - it's capable but at what cost to reliability and at what level of damage in the event of a 140mph dewirement, we don't know for certain.
Inevitably 140mph running would cause more damage during dewirements and I'd expect, given additional forces involved on contact wire and catenary wire, would increase the failure rate, particularly at locations where 140mph line speeds apply in both directions.
To support multiple pantograph operation at 140mph, you need a thicker contact wire to support higher tension, higher tension is needed to better resist oscillations in the contact wire forming, and thicker contact cable at higher tension is needed to support a higher pantograph uplift force so the pantograph at the rear of a formation can maintain more satisfactory contact with the contact wire, reducing arcing and damage to the pan carbon, which in turn increases the risk of contact wire damage and dewirements.
Higher tensions will also reduce lateral deflection in high winds and keep the contact wire closer to the centre of the pantograph in such conditions, provided the registration is maintained correctly. That's an issue on sections of the ECML thanks to BR's cheap foundations.
