Train à Grande Vitesse

For a train blog that’s in existence for quite a number of years that’s had posts on equipment ranging from the humble neighborhood LRV to the latest and greatest post futuristic looking Japanese very-high-speed electric multiple units, the omittance of possibly one of the most famous trainset in the Western World is, at least in my mind, quite unacceptable. It is not that I don’t have anything to say about the TGV, or literally, the High Speed Train, the problem is quite the contrary. There is so much to say about this topic, I don’t know where to begin or end. In no way, the few words I am about to scribble down here will do this great engineering achievement by GEC-Alsthom (now Alstom) the justice it deserves. Hopefully though, it will provide somewhat of a understandable overview of some of the interesting facts that sum up this Concord of the land is all about.

This is the beautiful high-speed train we are talking about here

I will note that this post is dedicated to what I call the first generation of the TGV, ones with power cars having the more angular nose designs than the later models, say the TGV Duplex.

I did mention some time ago, with the post about the TGV 001, that at the beginning, the TGV was meant to be powered by gas turbines rather than overhead catenaries. However after a certain oil crisis, electricity proved to be a more sustainable source of power in the long run, although it came with a higher price tag on initial infrastructure spending (just think of all the poles, arms, linkages, and copper wires). In my brief readings online (sources unverified by me), the T in TGV, rather than the word train, meant très (means “very” in French, remember, this was the 60s, sustained speeds of over 125 mph on land was considered very fast), or turbine.

The early TGVs are under refurbishment and will soon all wear this beautiful new Carmillon livery

To design and manufacture a high speed train, even in the modern day, is no small feat. At the time when trains still mostly had locomotives and screw couplers, there were quite a number of issues to address.

First and foremost, the amount and efficiency of traction power to propel such rail vehicle up to a satisfactory speed coupled with some sort of high performance running gears that would keep this said vehicle on the track all the time. Then there was the free slack between cars caused by the gaps between couplers, solutions already existed at the time and this should be a non-issue, but there were other factors to consider, to which the style of coupling could be a contributing factor. All this I’ve babbled on about is only a small subset of problems the rolling stock engineers need to solve. There is another, entirely different but also very important set of factors which I am not mentioning too much about here, namely, track, and signal (however, for starters, you can read all about them here on Wikipedia).

Eventually, the first production electric TGV, known as the TGV Sud-Est, took the form of a 10 car articulated EMU (loosely speaking, and read on for why) and entered service in 1981 on the LGV Sud-Est between Paris and Lyon. The TGV Sud-Est indeed looked like a conventional push-pull trainset with locomotives on either end, but one fact that was hard not to omit was that the third truck counting from either end, i.e. on the first passenger coach, was also powered. Combined, the 12 axles provided 9,100 tractive horsepower to propel the TGV at a maximum speed of 162 mph in service initially and 186 mph today. Trailing passenger cars shared Jacobs trucks between them, making a slackless and more rigid coupling. They also reduced tendency to jackknife and helped cars to stay upright in case of a derailment.

This picture of the Jacobs truck is really from the KTX-I, which is also a TGV

Several iterations of the TGV share similar physical appearance (later models had better aerodynamics, note above the windshield) and most have been strict push-pull trainsets except the EuroStar British Rail Class 373. On 18 May 1990, a modified TGV Atlantique no 325 set the world speed record at the time of 515.3 km/h or 320 mph on the LGV Atlantique.

TGV Atlantique, note the subtle difference in physical appearance

What achievements by these trains