WITH EVERY JULES VERNE NOVEL, James Bond film or World’s Fair came new, fantastical ways of getting around. They packed our near-future with science-fiction promises: walkways that did the walking for us, pod cars built for one, jet-powered backpacks that let humans fly. Today, although these things exist, they’re hardly commonplace. Why did these transportation moonshots fall by the wayside, and short of their pledges to revolutionise the world?

“I think we have a cultural affinity for technology that reflects optimism, but we all make poor forecasts,” says Jim Moore, director of the Transportation Engineering Program at the University of Southern California. He says that any tech that’s based on new standards for infrastructure, in particular, is risky. It requires sweeping changes, investments, and it penetrates the market slowly. That’s why monorails, despite their advantages over traditional rail locomotives, have largely been relegated to theme parks and Simpsons episodes.

“Public authority hates to be wrong in spectacular public ways, and thus opening itself to criticism on many fronts,” Moore says. While we’ve seen such feats as the Concorde and bullet trains come to fruition, transportation technologies can, overall, just be harder to get off the ground.

Here is a handful of examples that may not have made quite the seismic, Asimovian splash that was promised of them a century ago, despite the initial hype. But they can still be found today, if you know where to look.

Monorail

Then: There is likely no discarded transportation relic that sums up the past’s vision of the future better than the monorail. Inventors had been toying with the idea of an elevated, single rail line since the 1800s, and by 1956, Houston, Texas saw the first trial run of a monorail in the US, in all its shiny, glass-fibre glory. The otherworldly, curvy carriages that zoomed high above the ground popped up piecemeal around the world in places like Japan, but the turn of the century’s rise of the automobile proved too much for the sky high train of tomorrow.

Now: Today, monorails are chiefly the chariots of airport terminals and amusement parks. Disney World in Florida has a monorail system that shuttles Mickey lovers from car park to theme park — including a line that runs directly through the soaring lobby of Disney’s Contemporary Resort hotel.

It’s a shame that monorails haven’t reached the popularity expected of them in the ‘50s. They’re eco-friendly, quiet, and have strong safety records. There can be found in some cities around the world as a mass transit option, however. The 54-year-old Seattle Center Monorail, America’s first full-scale commercial monorail, runs every ten minutes and connects the neighbourhood around the Space Needle to the city centre. It debuted at the Seattle World’s Fair in 1962, and today, carries 2m passengers each year.

Moving walkways

Then: More than a century ago, moving sidewalks, also known as travelators, were another gushed-over transport tech that was supposed to change walking forever — by relieving us of the burden of it. The first moving walkway first appeared way back in 1893 at the World’s Columbian Exposition in Chicago, and showed up again seven years later at the world’s fair in Paris. These international exhibitions were famous for their charmingly far-fetched visions of the near future, and the idea of conveyor belt sidewalks was just one of many.

Now: Today, like monorails, sadly, they’re largely confined to airports for harried travelers clutching a boarding pass in one hand and an overpriced Egg McMuffin in another. In November, Boston’s Logan International Airport announced plans to build a 2,640 foot-long travelator that will link Terminal E with the Blue Line metro station.

Why do monorails and moving sidewalks crop up so often in airports, when ‘50s futurists had hopes of those technologies becoming transportation de rigueur? Moore says because airports, unlike big sprawling cities, are “controlled environments where expensive, high-maintenance technology can be deployed with relatively low risk, and where throughput is widely accepted by the public as a logical goal.” In other words, airports are ideal Petri dishes to test transportation technology, and besides — everyone wants to get in and out of those things as fast as humanly possible.

Pneumatic trains

Then: It sounds like an episode of Futurama, but some 150 years ago, some people wanted to develop pneumatic trains: underground cylindrical carriages, blasted by high-powered fans on either ends of long brick tunnels. It’s like being shuttled through one of those tubes at bank drive-throughs, like some kind of deposited cheque. In 1864, one such train was built underneath London’s Crystal Palace Park. Just a few years later, a wealthy American investor tried the same thing under New York City. Neither amounted to more than a short-lived novelty act.

Now: The closest thing we have to these odd tubular transport pods is the Hyperloop, a labour of love for Tesla Motors founder Elon Musk. The idea is that riders will cram inside a pressurised pod and be shot through a tube just six feet in diameter at over 1,200kph, making a journey from San Francisco to Los Angeles in 30 minutes. It sounds ridiculous — and dangerous — but design and testing are actually underway. In 2015, Musk’s aerospace outfit, SpaceX, sponsored a Hyperloop competition, seeking a design for the Hyperloop’s passenger pods. Entrants included 115 teams — all but one, an international group organized on Reddit, were comprised of university students. In January 2016, SpaceX invited 30 finalists to design working prototypes for evaluation on a one-mile Hyperloop test track in California.

Single-person car

Then: Following World War II, the microcar was born out of renewed innovation in the face of just-ended devastation, and amid a world of limited resources. The poster child for the breed is the Peel P50, a British-made three-wheeler — claimed to be the world’s smallest production car — that debuted inauspiciously in 1962. From its suitably tiny factory on the Isle of Man, the Peel Engineering Company produced only 50 examples of this 54in-long car, priced at £199 apiece. The company (better known for building the glass-fibre boats and fairings for racing motorbikes) quietly retired the P50 in 1965, but a memorable appearance on Top Gear Series 10 turned it into a 21st century object of desire, prompting a pair of businessmen, Gary Hillman and Faizal Khan, to revive the P50. The team introduced petrol and electric replica versions of the car, this time starting at a less-than-micro £10,000.

Now: These days, one-seaters are limited to go-karts, but occasionally a mainstream carmaker tries to run with the concept. Toyota — a car company famous for chasing charmingly bizarre transport technologies like handheld talking robots that sit in your cup holder — is working on one-person cars of its own, dubbing the trend “personal mobility” with its three-wheel i-Road electric vehicle. The company says the enclosed vehicle, which uses a clever articulated front suspension, is geared toward urban dwellers looking for speedier means of snaking through narrow alleyways and sinuous sidewalks.

Last July, after experimenting with concepts for other single-passenger vehicles that look more like wearable, wheeled robot suits, Toyota sent a fleet of i-Roads onto the streets of Tokyo as part of a one-year pilot program, as a follow-up to a similar run in October 2014 in Grenoble, France. Other companies have experimented with one-person cars, too, like Renault UK and Mazda with its bizarre car-in-a-suitcase. They’re still far from mainstream — but as city-wide bike and car-sharing services continue to take off, and as more cities install EV-juicing charging stations along their roads, a future filled with personal mini-cars may be closer than we think.

Jet pack

Then: They first appeared in pop culture in the form of comic books, but the idea for a computerized rucksack capable of transforming the wearer into a human rocket was pursued in earnest by the US military over 50 years ago. It even managed to build and demo one back in 1961. In 1965, Sean Connery donned a jetpack to escape gun-toting baddies in Thunderball, and in 1967, the public’s jetpack fetish came to a head when a pair of helmeted flyers buzzed the Los Angeles Memorial Coliseum during halftime of Super Bowl I — to the amazement of 60,000 spectators and a television audience of more than 50m.

Now: Jet packs still do technically exist, but they’re typically found in Hollywood stunts or eccentric tinkerers’ garages. Some jet packs use water to blast the wearer skyward. Technically, astronauts use “jet packs” in the form of propulsion units on the backs of their spacesuits to help spacewalkers drift in zero gravity with some semblance of control and direction.

Back in December 2014, a New Zealand company called Martin Jetpack announced its line of packs: carbon fibre and aluminium contraptions with petrol-powered fans for propulsion that can operate with or without a pilot. The company plans to commence deliveries if its first jetpacks late this year. The price? About £83,000.

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