Were there any advantages over normal trains except cool factor?
Taking the french Aérotrain advantages:
- Higher speed (due to inexistant rail drag)
- More comfortable
- Less noise
- Faster braking
- Way cheaper rails and maintenance (just concrete rails that don’t get rolled on, no steel)
- Rails can be easily elevated, taking less space on the ground and avoiding intersections with roads as well as landlocking. Basically, you can cross fields without bothering farmers too much
The trouble is you have to replace existing infrastructure which means as soon as you start ripping up old rail lines you can no longer run traditional trains so the level of service is actually going to go down not up. Hence why it was abandoned.
Any revolutionary train technology is going to have to work on the existing infrastructure, or it’s not going to happen regardless of how revolutionary it might otherwise be.
Yea no i ddont think that a train with a turbine that uses kerosene is so great. With regeular trains you can recouparate while braking. Why would the aeotrain brake faster than a regular train?
You’re talking about a 70’s prototype, but that does not mean it would need a kerosene turbine if it was made nowadays. Actually, the Aérotrain S44 used a linear electric motor.
A train brakes by blocking the wheels on two relatively small rails, and the wheels can lose traction.
An aerotrain reverses its propulsion, using it as a brake. No slippage possible here.
It can also bite the rail, having a way bigger braking surface, as well as having an interface dedicated to braking directly on the rail instead of a brake on a wheel on a rail.
And in emergencies, you can even stop the suspension and let the aerotrain rest directly on the rail to brake. That’s a bit brutal and causes damages (at least back in the 70’s), but that stops the Aérotrain quite fast and is way better than derailing or hitting something.
Ok so first if all anlinear electric motor is really expensive all the things that you said that were good about the aérotrain then dont apply annymore.
The amount of thrust you have to generate to stop a decently sized train is huge, that kind of turbine would be super loud and blow tons of debris around. If you brake with biting the rail you will also have lots of wear.
I dont even get why you would need to brake that fast? With a vehicle that heavy you will never be able to brake so fast that you could stop if something happened a hundret meters in fro t of you. And even if you bite down on the rail to stop near instantly the kinetic energy of a few hundret tons moving at lets say 70km/h would just destroy the rail.
Yes: speed. But if you weigh advantages against disadvantages (by far the largest being the need for completely new infrastructure), hover trains simply lost.
And not only in the UK, btw. Similar projects had been scrapped all over the world, for the same reasons.
I’m not sure about energy consumption; the video makes it sound like they used a lot of electricity but then I suspect normal high speed trains do as well.
I’m also unsure about the hovering being achieved by fans and not magnetic levitation. The video does not go deep enough there: was the former supposed to be supplanted by the latter, in time? I’m not an expert, but using strong fans to lift a 22t car off the tracks feels inferior to me, if magnets could achieve the same, probably consuming less energy and being less error prone.
According to the Wikipedia page the train did use ducted fans to hover. The big benefit there is the tracks are extraordinarily cheap, it’s just some concrete poured into a rough shape.
True, maglev requires more specialised tracks. Still, a whole new infrastructure - instead they ended up building a train that can swing to better adapt to their sometimes Victorian tracks.
They allowed for >250km/h speeds. They were basically competing technology and were developed at the same time as modern high speed rail (and lost).
I imagine they’d have less wear and tear and would require less maitenence would they not? Potentially at least depending on how they hover.
Trains already don’t require much maintenance, they’re quite simple machines, which is one of their main benefits.
The magnet for them is easily damaged by weather and the bending in curves
Not really. Needs its own rails too so you can’t use other trains on it or it on other tracks. Regular high speed trains are capable of going faster than UK speed limits anyway so really it would be better to upgrade the existing infrastructure to allow higher speeds if speed was a concern.
A high speed train can also go onto non high speed lines, just at a lower speed. The reverse is also possible although generally you want to avoid blocking up the line too much with slower trains.
Build HS2 and then start HS3-12. Tell NIMBYs to go fuck themselves.
Speed, at the cost of an incompatible and more expensive infrastructure, and even “regular” raillines are now can be upgraded to 300km/h.
Except here in the UK where everything is old and the only option is to spend more money than the entire EU continent wide rail linkup project (Twice over I think now?) on 30 miles of track.
even “regular” raillines are now can be upgraded
I assume this is contingent on the existing line being fairly straight and direct? Where I live, the tracks are very meandering to navigate hills and valleys, and train staff told me the chance of an upgrade was basically zero.
Definitely impossible for most tracks. Possible for some, but at high costs. Germans have been upgrading some lines for decades now… The best (worst) example being the north-south towards Basel. For high speed the paths need to be further apart from eachother, there need to be better barriers between tracks and what’s around them, the curves indeed need to be wider, the ‘tilt’ in the track in curves might need to be adjusted too… All of which leads to necessity of many new bridges and tunnels where this upgrading is impossible due to surroundings. It costs many millions of € per km and many decades to accomplish. The French on the other hand mainly went for “build new lines”, it was clearly the better approach to get shit done fast (tho skipping many possible stops altogether on the new lines).
It’s possible to upgrade a line like that, but it will involve a lot of cutting through hills or building bridges over valleys
Isn’t that fundamentally just making a new line?
It could take the same route, just flattening out the hills and valleys.
If there are sharp corners that might not work, but even lower speed rail doesn’t really like sharp corners. They can be mitigated up to a certain point with banked curves.
Fucking tech bros. Hovertrains are stupid, inefficient and expensive
So just keep one running to look cool.
I love Cold War era “throwing technology at the wall to see what sticks” projects. So many ideas were tried and often the ideas themselves weren’t bad but something else was a limiting factor (e.g. our level of material science technology at the time). Even so, they’d often get a lot further than one could reasonably expect, which is rather cool.
Heath was prime minister for this with Thatcher in his cabinet, right? (albeit she was focused on stealing milk from kids at the time)
Neoliberals ruining our country’s potential for half a century now 🎉
I mean… this thing just ate energy. The prototype car was pulling 6.5kV off the conducting rails to keep the air jets running hard enough for the hovering, and it wasn’t even carrying a passenger load. If you add more weight you have to add more air thrust to keep hovering, which means bigger engines and more power, and the production model will need extras for redundancy because if the air cushion weakens while you’re doing 200+kph and the car just grazes the track you’re in big trouble. I seriously doubt this concept can scale up to a working transit system and be at all safe. The electricity input alone would be a hazard.
I’ll bet it sounded like a Harrier from the outside too.
Also what do you think the vortex is like above the air intakes? I’m imagining this thing cruising along sucking in birds and just flushing them straight down onto the track as it travels the countryside.
I was really skeptical about the air hovering, as opposed to magnetic. The video did not go deep enough there imho. They were planning to switch the project to maglev? Or did he just put that in as a historical comparison?
As a layman, it seems to me magnetic levitation would consume significantly less energy, and probably be less error prone.
It’s a shame that these cool things are probably too expensive. The Transrapid, a hover train from Germany, unfortunately also failed to catch on, but at least one commercial line was built in China connecting Shanghai Pudong International Airport with Longyang Road Station in the city, which is still in operation today.
It’s the same situation as maglev trains cool but impractical.
Didn’t everyone do that in the 70s? Maybe even the us did it (not sure).
France also did in the 60s I think. So yes everyone did.
Similar projects popped up across the globe at that time, and were scrapped for the same reasons: the need for a completely new infrastructure.
I also suspect hover trains weren’t consuming less energy than conventional. So the only advantage you get are higher speeds. The numbers simply didn’t add up.
