Saturday, 12 April 2014

Track edition


Travelling on the train as I do from time to time the continuing controversy over the HS2 London-Manchester high speed service continues to intrigue me.
As I experienced this week the problems that can happen on a very busy stretch where I train has a breakdown or similar difficulty often has a knock on effect on other services such as delays or even cancellations.
On the other hand a report of MP's suggests the proposed new line and service should operate no faster than 185 MPH for environmental reasons (C02 emissions) rather than the original reducing considerably the 'improved' journey times for being say not more than twenty minutes and as some of these stations are not going to be the existing ones, passengers may need to pick up connecting services or taxis to traditional business destinations making any savings over the standard services pretty much academic being unlikely to encourage such users to switch.
One alternative might be to increase capacity on the existing networks by introducing and in some instances restoring twin track working in which was removed for cost reasons in the 70's and 80's and finishing of electrification allowing trains to operate to a maximum of 125 MPH which would still offer advantages over the road network.
This could benefit a wider geographic area and customer base.

1 comment:

mittfh said...

Interestingly, 186 mph (300 kph) is the line speed of High Speed 1 plus the main North-South High Speed line through France. Much of the justification for the higher line speed (initially 225 mph / 360 kph but with a maximum design speed of 250 mph / 400 kph - far higher than the 200 mph / 320 kph used on the highest speed lines elsewhere in Europe) was that business people would be unable to do any work on the train, thus it was imperative to get them to work asap.

Unfortunately, such a high line speed means the train would have to take a very direct route, with minimal curvature or gradients - hence Phase 1 will cut through 33 ancient woods (areas continuously wooded since 1600), 4 SSSIs, 400 houses and involve the construction of 22.5 miles (36.2 km) of tunnel and 40 miles (64 km) on viaduct or embankment.

While a lower design speed would delay the start of construction (currently scheduled to start in 2018 and last 6½ years, with the opening in 2025-6), by allowing more gradients and bends, the revised route could use less terraforming and avoid many of the more contentious sites thus potentially saving money on the construction costs.

Meanwhile, given the first phase of the route would take at least 12 years before opening, there have been some plans brought forward to upgrade existing lines - the Chiltern Line (London Marylebone to Birmingham Moor Street) has already been scheduled for electrification - although that project's been in the pipeline for decades given the bridges along the route were raised in the 1980s in anticipation (!)