Not so fast

I've written before about the utter foolishness embedded in the whole concept of HS2: the conceit that the trains needed to be the fastest in the world. A decision made in May was taken to run the trains at lower speeds than their full capability - basically at conventional high speeds - to save time and also money on the ever escalating final cost, which the Independent has pointed out is now expected to be more than the cost of NASA's Artemis moon mission.

How did we get here?

The question of whether to run at lower speeds stemmed from a safety certification issue. Because the trains were due to run so fast they couldn't be tested on the current infrastructure so would have to have been sent abroad, or wait for the new line to be totally ready before the final certification process could be started. Without such certification the trains can't carry passengers. Cutting speed so the trains can be tested on current infrastructure brings forward the much delayed commissioning date (or rather stops it going back even further) and saves cost.

But why was HS2 designed for such high speeds?

David Cameron's government allowed themselves to be beguiled by the rail industry advisers who said that we would regret it if we chose to stick with the then current technology (indeed, quite old technology) of HS1, whose trains run at 300kph. The top speed on the rest of the UK rail network is 200kph. 

If you start out on a long infrastructure project with current technology then you risk being out of date by the time it is commissioned. So the vanity project's trains were specified to run at 360 kilometres per hour (224 mph in old money). This  would make them among the fastest in the world. There are trains now running in China and Indonesia at 350kph. So the advisors were right in a way - things have moved on.

 An HS2 train, from HS2 website

But what benefit would there be in such high speeds when we live in a relatively small country? And how much extra would it cost?

From HS2's very first gleam in the eye stage, I questioned whether there was any real benefit in ultra high speed. This didn't make me appear as much of an oddball in the rail industry as questioning the rationale for fast breeder reactors as I had when I was in the nuclear industry (see The Germans have a word for it, 27 March 2026). A lot of my much more knowledgable colleagues were saying the same. 

The business case for HS2 was substantially made by some simple (one might say simplistic) sums based on time saving. Having made, successfully but with some embarrassment because I thought it was tosh, a case to the company's board to upgrade our IT systems based on a notional saving of a few minutes per day multiplied by our number of staff, I felt this type of argument was a load of bull. However, I was certain that particular investment would pay off - and it did. We just needed a case the board could approve. In the case of HS2 I suspect the designers also knew that applying a financial benefit to a few minutes saved multiplied by the numbers of passengers was dodgy to say the least. Speaking purely personally I would have been inclined to take the benefit of a few minutes saved on my journeys to London for meetings either by having a few more minutes in bed or fitting in a nicer cup of coffee on arrival rather than on the train. 

The point that makes me weep is that the ultra high speed argument was so unnecessary. By the noughties there were more rail passengers journeys in the UK than ever. The previous high, in 1947 had been followed by a long decline until, co-incidentally or not, the graph started an inexorable recovery around the time of rail privatisation in 1996. It was clear that the network was coming under strain on grounds of capacity. A new direct north-south line would bring that extra capacity and it would also bring faster journeys by having fewer stations to stop at. With conventional high speed, the same as HS1, there would still be shorter intercity journeys. The marginal benefit from uber high speed was always minuscule.

Indeed, with a huge degree of brass neck, HS2 say on their website that the speed reduction from 360kph to 320kph will only mean a 3 minute longer journey to Birmingham from Old Oak Common in London. (I note they don't say Euston so I presume the decision on whether to take the line all the way into Euston, as planned but at significant cost has not been made yet. I guess that could always been done later).

As for cost an old colleague and friend of mine who worked in railway technology man and boy once explained to me in the very simple words a man who really knows his subject uses. You see Phil, he said, high speed hammers the hell out of track. This is because they have to use higher grade steels and check, inspect and maintain it a lot more. When I spoke to him recently he summed it up even more concisely: "cost = speed squared".

HS2 don't make any promises on their website how much time and cost will be "saved" by reducing the speed, only that it increases "the likelihood of opening as early as possible and at the lowest reasonable cost". But other sources refer to curbing "gold plating" from "over-engineered specifications and an excessive focus on achieving the absolute highest possible speeds" which reviews had identified as faults in the project's management. I'd say faults in the projects inception, approval and direction actually rather than the poor buggers who were tasked with delivering it.

There were plenty of people in the business who knew what would happen when HS2 set out on it's vanity project and my buddy was one of them. Unfortunately the dreamers were in charge and the politicians were seduced and didn't ask the right questions.

I still wouldn't like to put a probability on me being around to ride on HS2!

Not so fast! HS2 to save billions by slowing trains Sunday Times 22 March 2026

The HS2 website, https://www.hs2.org.uk/construction/trains-and-depots/ noted the decision to reduce spped had been made by May 2026

The Independent, 19 May 2026. HS2 cuts train speeds as project to cost more than NASA's Artemis moon mission, https://www.independent.co.uk/bulletin/news/hs2-slower-speeds-costs-heidi-alexander-b2979336.html