This is actually awesome.

Steam engines are indeed powerful. Some past designs were a bit on the dangerous side but modern technology should address most of those concerns. We lived close to the Union Pacific mainline running through Nebraska and my cousins in Texas called my brothers liars when they talked about the speed of the trains coming through shortly after WWII. When they came up to visit, their jobs dropped when my brother top ended his car on the highway alongside the track. The train left them in the dust. Of course the train wrecks were fairly frequent and quite spectacular and the carnage from teenagers trying to beat the train was heartbreaking. Ahh, the memories.

It's too bad the world went from steam to fossil fuels before going to electric and solar. We should have stuck with steam until we went solar the world would be a better place today if we had.

Very odd. I would have thought a cleaner fuel system would be desirable. Natural gas to heat the boiler? No idea if sufficient compressed NG could be carried but 9 tons of coal would suggest so. Steam was ever a low-maintenance power source.

It may be the most modern steam locomotive, and newly built, but it is old-fashioned. Modern things have better efficiency and burn less carbon. Seven billion people can't behave like a few million rich ones did a century ago without killing their planet.

@JimFox - A very natural progression you would have thought... There must be a legal/practical reason why this has not happened, now or in the past. It would certainly make the job of the 'stoker' a lot easier (and cleaner)! I can remember traveling up to London from Devon in about 1967 (aged 6) on a steam-pulled train and making the mistake of sticking my head out of the window at an inopportune moment only to get a face (and eyes) full of soot from the chuffing engine.
What is most noteworthy from this story, though, is that the fastest engine back then (the Mallard mentioned in the article) was just as fast as our fastest regular trains today (the InterCity 125s). Have we *really* not progressed here *at all*?! A very sad inditement of successive governmental failures if ever I saw one. Perhaps we could scrap HS2 (High Speed (rail) 2) and just jump on the Hyperloop!

StefanSchmidt April 14th, 2017 says: "This is actually awesome."
Exactly so! And, unlike all these super-clean modern high-efficiency devices, it's got SOUL!

This is a tremendous achievement- a wonderful piece of 'living history'.
@Martin Winlow, actually we have progressed massively since the days of the Mallard- yes, it did 126mph once- in highly favourable conditions- but at the expense of the track and it damaged the locomotive itself to some extent (all repairable thankfully). The modern HST (and others) can do 125mph day in, day out, can easily out-accelerate and out-brake a steam-hauled train, and in fact is capable of over 150mph flat out, if unrestricted. The A4 locomotive class (of which the Mallard is a member) could only operate up to 90mph in normal service.
The reason the HST (and others) are restricted to 125 is to do with the fact that our rail infrastructure is saturated, has to share track with slower local or freight trains, is mostly Victorian in origin, has sharp curves, etc. Huge improvements have been made to the rail network to allow faster running (often not apparent to most lay persons) but there is a limit to what can be squeezed out of our ageing network.
Hyperloop is a grand concept, but there will always be a need for heavy rail- so High Speed 2 is very much needed and will always be needed even if hyperloop proves to be viable (and unlike HS2 it has never been costed for building long distance in the UK).

@Martin Winlow- Last time I used the Inter City 125, it still took an HOUR to travel 40 miles Exeter-Plymouth. Problem is not the rolling stock but our rail infrastructure, much of it from the Brunel era! There can be no Bullet Trains in Uk without billions spent on complete track, signal & safety replacement. Not upgrade, replacement.

@LarryWolf- If we had stuck with steam then coal would have continued as fuel; possibly oil later, but not much cleaner- and it underwrites Islamic terror. Whilst it may seem pie-in-the -sky, it IS possible that trains & large vessels could be powered by Molten Salt Reactors; they can be small, modular and fail-safe, producing tiny quantities of actinides that can be sealed in glass for safety. One such produced power for 4 years at Oak Ridge National Laboratory under Alvin Weinberg's team in the early 60's but was shut down in favour of PWR's to produce plutonium for weapons...