The crazy story of the Aérotrain: what if the TGV had never existed?

Written by Sophie Renassia

Published on May 10, 2025

Imagine for a moment: Paris-Orléans in just 20 minutes, at 430 km/h thanks to a train levitating on an air cushion, never touching the rails... What if we told you that this revolutionary, faster, and wheel-less train had already been designed, and that it could have forever changed the future of transport? What if the TGV had never existed, to be replaced by this revolutionary train? Today, all that remains of this visionary dream is a long concrete ramp overtaken by ivy between Beauce and Sologne, alongside the A19. But why? How was such a spectacular breakthrough abandoned? Dive into one of the wildest (and least known) technological sagas of the 20th century: the Aérotrain.

The Wild Dream of a Visionary Engineer

1960: France Wants to Go (Much) Faster

What if the hum of the TGVs we know today was just a plan B? Between the late 1950s and the 1973 oil crisis, France cherished a very different fantasy: to travel from Paris to Orléans in twenty minutes, with the cars literally suspended on an air cushion. This dream had a name – the Aérotrain – and a father, Jean Bertin, a brilliant jack-of-all-trades who believed a wheel-less train was possible at a time when commercial speed topped out at 160 km/h.

To better understand, we must go back to the heart of the Trente Glorieuses (Thirty Glorious Years), when everything seemed possible. Highways stretched like new ribbons, oil flowed cheaply, and the airliner became a national symbol with the Caravelle. Yet, on the railways, progress was slow. The fastest express trains still took a full day to reach Marseille from Paris. This slowness annoyed the political powers who wanted to project French modernity to the farthest corners of the country. When de Gaulle, and then Pompidou, hammered home the term "grand projet" (major project), they were thinking of course of the Concorde and nuclear power plants, but also of a rail system finally worthy of France's industrial momentum.

Jean Bertin's Wild Idea: Railway Levitation

It was in this climate of technical euphoria that Jean Bertin, a former Airbus employee before its time and a graduate of the École Polytechnique, became convinced that the problem could be eliminated at its root: if friction slows down trains, let's eliminate friction. Inspired by both the English hovercraft and the gas dynamics in turbojets, he imagined as early as 1957 a cabin that no longer "rolls" but glides, carried by a curtain of compressed air. The track became an inverted T-shaped monorail, which allowed for less friction and therefore more speed. The engine blew under the chassis, and the cabin lifted a few millimeters. It was small, but enough to eliminate almost all mechanical resistance.

In 1963, with a model under his arm, he secured a meeting with Georges Pompidou, then Prime Minister. Pompidou was won over and signed a check for three million francs to build a first prototype of this "plane on rails." The machine reached 90 km/h in 1965, 200 km/h in the heart of Beauce the following year, and was already riding a wave of national optimism.

Records, Glitter, and Promises: The Aérotrain Gathers Pace

Dizzying Figures

In the late 1960s, the country lived in the era of Apollo 11 and the turbojet, and each new Aérotrain record made headlines. In 1969, on the Saran test track, prototype 02 was already hitting 422 km/h, not on rails but on that famous invisible cushion. Engineers spoke of a margin of 500 km/h, or even more if they switched to second-generation reactors.

The moment was euphoric: France promised the international press a twenty-minute Lyon–Grenoble shuttle for the 1968 Olympics. Was the deadline untenable? No matter, the idea was enough to sell glossy magazines.

From Beauce to the White House

The shockwave crossed the Atlantic: in 1971, Richard Nixon sent a special advisor to Gometz-la-Ville to ride aboard. Across the Rhine, the Deutsche Bundesbahn (DB) observed the machine with a mixture of envy and skepticism; the Japanese, for their part, took notes that would later influence the SCMaglev.

In Paris, the Ministry of Equipment funded the project; 45 million francs were allocated for a 26-meter train, two turning platforms, and eighteen kilometers of concrete beams. On March 5, 1974, the I80-HV tore through the air at 430.4 km/h. On paper, nothing could stop this land-based rocket.

When Politics and Oil Cut the Engine

Pompidou Passes Away, Giscard Changes the Game

On April 2, 1974, Georges Pompidou died at the Élysée Palace. His successor, Valéry Giscard d'Estaing, inherited a country suddenly hit by the first oil crisis. The days of open checkbooks were over: budgetary realism was the new mantra.

However, the Aérotrain depended on a fuel that was now volatile and entirely new tracks, while the SNCF's experimental TGV, though less fast, connected to catenaries and promised to eventually reuse part of the existing network. Giscard preferred to modernize what already existed: the TGV seemed cheaper and less fuel-intensive.

The Flaws That Became Deal-Breakers

With the economic crisis, each weakness of the Aérotrain magnified under scrutiny. The concrete beams upset local residents; the U-turns on platforms complicated operations; the train carried only about a hundred passengers, far fewer than the 500 of a TGV. Worse: the state calculated that doubling the speed compared to electric rail quadrupled the energy bill. In this anxious climate, the SNCF discreetly undermined its rival.

In summary: costly infrastructure (hundreds of kilometers of concrete beams were needed), limited capacity (80 seats compared to 500 for a TGV), complex maneuvers (U-turns on rotating platforms)... On July 17, 1974, the ax fell: the project was officially terminated, pack up the models. Jean Bertin fought for a few months, then saw his funding evaporate. He died on December 21, 1975, at the age of 58, leaving behind more than 3,000 patents and a bitter taste of missed opportunity...

A Concrete Relic in the Heart of Beauce

The Saran Test Ramp: A Ghost Classified as a Monument

Today, if you take the A19 towards Orléans, you can see it: an eighteen-kilometer white-gray viaduct, truncated, covered in ivy, and endlessly tagged with graffiti. Demolishing it would cost around 13 million euros, so the state preferred to classify it as "20th Century Heritage" in 2017. A few educational panels recall that here, in 1974, France flirted with Mach 0.35.

The (Futile) Attempts at Resurrection

Today, the site attracts many startups. In 2016, the company Spacetrain announced its intention to revive air cushions by replacing kerosene with hydrogen. The company occupied a hangar, presented an elegant carbon fiber demonstrator... but was convicted of fraud in 2023. Since then, the Aérotrain's rails continue to rust as much as they fascinate.

A Legacy That Still Hovers

From the Japanese Maglev to the American Hyperloop

Engineers never let a good idea die, and several countries seem to want to take up the French torch. In Japan, Japan Railways developed the SCMaglev from the 1970s: the same levitation logic, but via superconducting magnets cooled with liquid nitrogen. In 2015, the L0 test train set an incredible record at 603 km/h. Germany, for its part, tested the Transrapid between Berlin and Hamburg, but had to abandon it in 2006 after a fatal accident and a cost deemed prohibitive.

In 2013, Elon Musk published a white paper on the Hyperloop (spoiler: we'll tell you about it soon in another analysis!), a capsule propelled in a vacuum tube. The concept takes up Bertin's credo: eliminate friction, this time not only on the ground but also in the air. Several companies, including HyperloopTT and Hardt, continue to seek the solution, but no commercial line has yet seen the light of day.

The Big Question: Pay More to Go (Even) Faster?

Meanwhile, the French TGV still holds a rail record at 574.8 km/h (2007), but only operates at 320 km/h in regular service. Why? Because beyond that, the ticket price would soar as much as electricity consumption. Each additional km/h makes the curves explode: energy, CO₂, euros. The real equation is societal: speed, price, carbon footprint, local acceptability. Is the fantasy of saving ten minutes on a Paris–Lyon trip worth billions of euros and kilotons of CO₂? The answer is debated, but one thing remains certain: Jean Bertin's intuition still fuels research, from the choice of lightweight alloys to the aerodynamics of the latest generation of train noses.

To go further: High-Speed Rail: Is China Revolutionizing Rail Travel?

Jean Bertin aimed for the stars; his dream ended up in the graveyard of ideas that were too expensive. Yet, his Aérotrain paved the way (no pun intended) for all levitation utopias. So... What if Pompidou had lived? What if black gold hadn't skyrocketed? Would we be floating at 430 km/h today, rather than in a TGV? We can't rewrite history, but one thing is certain, the Aérotrain has left a lasting mark on high-speed transport technologies: lightness of materials with the use of aluminum, reduction of friction, and energy optimization... So many innovations signed by Jean Bertin, which still resonate today.

And if one day a wheel-less train finally sees the light of day in France, we will remember the Aérotrain and the fact that before the Hyperloop or the Maglev, France had already invented the train of the future...