The rail exception that proves the rule

S03E03: The 12 stages of train approval

Since the first edition of Midnight Weekly went out, we’ve run various series of articles allowing you to find out more about how we’re going about creating our ‘hotel on rails’ company (and you’ve lapped them up). So by popular demand, here’s another season; this is the third of four instalments.

Following our beginners’ guides to buying trains and designing trains, this new season aims to help you better understand railway regulation in Europe, and thus everything Midnight Trains is having to reckon with before we can welcome you on board our trains from early 2024. Having told you about the huge regulatory changes that have taken place in the rail industry over the past decades, now we’ll be tackling the specifics of the trains themselves. In a sector where responsibilities are pretty fragmented, there are multiple manufacturers and with the growing need for interoperability, what rules must new trains respect and how do you ensure they remain compatible with the existing infrastructure?

Let’s start with the rules of creation. There are a few train parts that have remained similar since the very beginning of the rails: train coupling hasn’t evolved much at all, for example. Gauge width, rather fortunately, hasn’t either. Since 1922, the International Union of Railways was founded, and has played a huge role in the standardisation of train parts.

Now Europe has picked up the baton. The rules of creation and approval of train parts are becoming ever-more similar, many of them being described by Continent-wide texts (notably the Technical Specification of Interoperability Locomotive and Passengers, or STI Loc & Pas): from the performance level of the brakes to the notes of overhead warnings, everything has been thought out. Equipment that meets the STI is able to go everywhere, excepting a few country-specific rules. And it should be notest that the European Railway Agency also tries to make sure that those rules are fair and don’t impact on market openness.

The approval process then plays a central part. During the production of train parts, the manufacturer is responsible for making sure it conforms to the STI. It chooses a certification organisation – a so-called ‘notified body’ – which will ensure not only that all applicable rules are respected from the start, but will also verify the actual compatibility of it all, too. Certain components will have already been tested, but in most cases, a whole series of trials will be required.

For example, you would verify the shuntage of track circuits and the impact of possible disturbing currents generated by the movement of vehicles. In France, these tests are often carried out in Plouaret in Brittany, where the salinity is at its highest. The pantographs are also checked both while trains are running and not, to ensure they don’t damage the overhead lines. The brakes are often checked, too (often just after the engine has started, to get the best sense of whether they’re working properly). The process of restarting while on a slope can also be tested: one of the best testing sites is the incredibly steep climb of the Capvern in the Pyrénées.

A few special dedicated circuits exist for some of these tests (to avoid them taking over lines where commercial services run). The Velim test ring (Czech Republic) has no doubt seen some of the most action across its 15 kilometres, whose curvature allows trains to reach up to 230 kilometres per hour. In Petit Forêt, not far from Valenciennes, a more modest installation exists, as well as a climatic chamber allowing you to check things function well under different temperatures.

Clearly, the particularities of each railway network have to be taken into account, too. Not only do certain infrastructures have different sizes – French models tend to have narrower chassis than German ones, for example – but obstacles and time limitations may also exist. The operators must therefore check the compatibility of their trains with the Registre de l’Infrastructure Ferroviaire (RINF), which applies across Europe.

It might make you laugh, but if you live in France, you may remember the very haphazard introduction of Regio2N in France – two-floor TERs – in 2015. The reason for its ills? An innovative set-up with both shorter and wider chassis, sometimes incompatible with the platforms (no longer of the desired geometrical norms), often due to wear and tear. It caused a lot of damage to the reputation of SNCF as a whole.

Next week, in our next episode, we’ll be tackling the timetabling of trains: how exactly you might go about scheduling arrivals and departures.

Midnight Trains Logo