HS2 Ltd's chief executive Mark Thurston has told a meeting of the All-Party Parliamentary Rail Group that train speeds and frequency on the new line could be changed to reduce costs, says the Evening Standard.
Its report says the options discussed included lowering train speeds by around 50kmph (30mph), reducing train numbers from 18 to 14 per hour and changing from slab to ballast track.
A low-speed high-speed train would be a perfect symbol of the dynamic new Brexit Britain.
More and more, politics today reminds me of the early 1970s, when prestige projects were promoted and then abandoned.
There was the third London airport at Maplin (announced 1971, abandoned 1974), the Channel Tunnel (started 1974, abandoned 1975) and Concorde, which was kept going, but proved hard to sell to anyone but Britain and France's national airlines.
HS2, you may recall, was approved by David Cameron, as a way of making good on his pledge not to build another runway at Heathrow.
Then came Theresa May, Brexit and the need for a new prestige project to show that Britain was open to the world. So a new runway was announced after all.
Ever since that, HS2 has been in danger of looking a bit of a white elephant.
I suspect it will be built from London to Birmingham, but it will be a long time before it gets any further than that.
However fast it runs.
There are two good technological reasons for slowing down HS2 train speeds.
ReplyDelete1) Slower trains mean you can have smaller radius curves, which gives you more flexibility over the route. Reducing the top speed from 225 mph to 195 mph means that you can reduce curve radius to 75% of what it would need to be at 225 mph. The time saving from the extra 30 mph is negligible.
2) The higher speed means that you have to have a stiffer trackbed (slab) to avoid the risk of Rayleigh waves causing train derailments. Keeping the speed down to no faster than HS1 means that we can use conventional track beds (ballast) where we already have experience.