On July 18th, 2018 we learned about

Engineers’ brief attempts to speed up trains with airplane engines

When I first read my kids the story of “Thomas and the Jet Engine,” I treated it as nothing more than fan service for kids. Sure, the idea of their favorite train being temporarily boosted across the tracks by a jet engine was fun, but clearly ridiculous. And of course, I was wrong. Not only have there been real attempts to build trains powered like aircraft, but working prototypes powered by jet aircraft have been built in multiple countries. These experimental trains were designed to join the speed of air travel with the hauling capacity of trains, although none of them ever went into regular, if speedy, service.

Pushed and pulled by propellers

The very first attempt at a plane/train hybrid was the railplane. George Bennie created a vertically oriented track that was intended to be built above existing railways, saving space and simplifying logistics. At the front and back of the pill-shaped vehicle, electric motors drove large propellers so that the railplane could ‘fly’ down the track without worrying about actual flight. The test track was too short to confirm it, but Bennie estimated that the railplane could have traveled as fast as 120 miles-per-hour, beating even today’s travel times. Unfortunately, Bennie couldn’t get enough funding to continue developing his prop-propelled train, leaving us only with advertisements and some footage of the prototype.

Jet-powered propulsion

With airplanes shifting to jet engines in the 1950s, trains in the 1960s had some catching up to do. By 1966, multiple parties were looking to either retrofit or design jet-powered trains from scratch. In France, Jean Bertin started work on the Aérotrain, which was designed to hover on an air-cushion atop an elevated track. The hovering was intended to reduce friction, making it easier for the Aérotrain’s single jet engine to propel the train down the track. Multiple rounds of prototypes were developed, including an 80-passenger train that could reach 155 miles-per-hour under the power of two jet-engines. Like the railplane before it, the Aérotrain was eventually abandoned in 1977 due to funding problems, although you can still find sections of test track France and near Pueblo, Colorado.

In the United States, turbojet train development looked a bit more like a retrofit. Don Wetzel led an effort to make trains faster and cheaper, which translated to front-mounted jet engines on an otherwise traditional-looking commuter train. Early iterations used recycled General Electric jet engines, purchased from the Air Force. Like the Aérotrain, Wetzel’s jet-powered trains never progressed past test tracks and prototypes, although they did manage to hit an impressive 183 miles-per-hour before the project was shut down.

Even if commuters never got to enjoy jet-engine speeds on the rails, these efforts caught the attention of engineers in the Soviet Union. With long-distance travel served by rail, plus a Cold War competitive spirit, the Speed Wagon Laboratory started work on their own jet-train in the late 60s as well. Target speeds ranged from 155 to a theoretical 223 miles-per-hour, but the project was dropped in the 1970s, partially thanks to the expenses associated with all the jet fuel those speeds would require.

Rounding things out, Japan had their own attempt at jet-powered trains, starting around 1968. Engineer Hisanojo Ozawa offered a few twists on the “common” jet-train design, aiming for a train with three jet engines that ran on rollers instead of traditional, flanged train tracks. The project didn’t seem to progress past a working scale-model, although that model predicted speeds up to 733 miles-per-hour.

Floating but not based on flight

Like Thomas the Tank Engine’s accidental sprint across the Island of Sodor, the age of jet-powered trains was short-lived. Fuel and other expenses made this form of propulsion less attractive, and so high-speed train designs have moved on to other design concepts, mostly. While not explicitly modeled after air travel, maglev trains do hover over the ground to reduce friction, allowing them to reach speeds of up to 249 miles-per-hour. The form of propulsion is different, but the basic premise of track-based transportation still appears to be one of our most practical ways to cross long distances.

Source: Turbojet train, Wikipedia