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Comment by tialaramex | Hacker News Reader

It's futile to actually have road-legal cars that go this fast because you can't do very much useful with the speed.

This is much too fast for the human operator (driver) to safely react to things outside the cockpit, which is why for example Britain owns trains capable of 140mph in service but deliberately limits them to 125mph. Tests suggested drivers couldn't be relied on to reliably observe and react to a lineside signal (showing e.g. double amber, "Prepare to find the next signal at: Prepare to find the next signal at: Danger") passed at 140mph. The "obvious" upgrade is to put the signals inside the cab with the driver, and that's how high speed trains work. But a car doesn't have in-cab signals either, and it has a LOT more external signals to respond to, including several signs we see in that video.

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This is why the TGV has no signals. Instead it uses a radio communication system. If no radio signal is received within a time frame, the train will warn the driver, and eventually stop. If a train has to perform an emergency stop, all other trains behind it are informed via the same system. If the driver does not react, the train will stop itself.

There is a reason why the TGV has seen no accidents since its launch in 1981.

As for a car, yeah, it's mostly a gimmick. Still incredible engineering, though.

The most important reason why the TGV has not had any accidents is actually a really simple one: it only runs on very high quality rails with large turn radii and excellent maintenance of the railbed.

And even that is not entirely true. The TGV can only run this fast because it runs on tracks where only the TGV is allowed.

The rail bed is even not that great, that's why only some ICEs are allowed on TGV routes, because they need a special deflector which is more robust to tolerate the stones which are thrown up in the air when the train drives over it.

I think they took this in consideration when they designed the latest iteration of the ICE.

I'm not sure that's entirely correct.

If https://en.wikipedia.org/wiki/High-speed_rail_in_France is to be believed, the high speed lines for TGV are primarily but not exclusively used for TGV:

"LGVs are reserved primarily for TGVs. One reason for this is that line capacity is sharply reduced when trains of differing speeds are mixed, ..." "Some stretches of less-used LGV are routinely mixed-traffic, such as the Tours branch ..." "Outside France, LGV-type lines often carry non-TGV intercity traffic, often as a requirement of the initial funding commitments."

I'm also not so sure about the quality of the rail bed:

"Track alignment is more precise than on normal railway lines, and ballast is in a deeper-than-normal profile, resulting in increased load-bearing capacity and track stability. "

While it may be safe, no accidents since launch might be a bit of an overstatement: https://en.m.wikipedia.org/wiki/List_of_TGV_accidents

OK, you're right. I should have clarified my statement; there have been no serious incidents on LGV tracks while in service. Level crossing accidents and collisions take place outside the LGV tracks, when the TGV run on standard railway tracks. Only one high speed derailment caused fatalities, and that was during a test run.

Thanks I'd never seen this. So there have been quite a few incidents, but the takeway at the top seems to be there has been no fatality “at high-speed”. I guess that's something to be proud of, but that's still far from a perfect track record.

Pretty much all modern cars will go faster than is useful and/or safe. Only a small set of public roads allow cars to go their top speed. I have a 1991 Corvette that will go 153 mph, and I've only done it twice. It scares the crap out of me. Top speed is a cool thing to boast about, but most people won't ever see it, and a few stupid people will hurt themselves with it. That's okay on the balance, because millionaires are spending their money and supporting the economy. Buying one of these cars probably funds an engineer's salary and likely a few others supplying materials to Bugatti.

Also Bugatti is part of the VW Group - so it's possible that some day the engineering may trickle down to all of the other brands in the group (such as the humble Skodas I've been driving for the last few years).

perhaps chassis and suspension may benefit but with rapid electrification impending in the future, even that is of dubious value.

A Bugatti is like a piece of jewelry in my opinion - beautiful but of no practical value.

Electric cars still have chassis and suspension?

No, electric cars are completely different from regular cars. You really have to approach their design from a software-oriented perspective.

> "some day the engineering may trickle down"

Do we also have trickle-down engineering now? Is economics not enough for that?

If you haven't pushed it on a race track with long straights, you have to try. I don't know how 1991 Corvette feels at high speeds but in newer sports cars, the long straight will seem like the time to relax a little, even in the 150s.

  a few stupid people will hurt themselves with it. That's okay on the balance, because millionaires are spending their money and supporting the economy.

I fail to see how that is ok.

> a few stupid people will hurt themselves and some randomly selected passers-by with it

I fail to see how that is ok.

A little bit of chlorine in the gene pool is often beneficial for mankind.

Adults should be free to engage in dangerous activities. The unfortunate problems are 1) they can and do hurt other people and 2) they hurt themselves and subsequently become vegetables and wards of the state.

That's why we have laws against (some) dangerous behavior. It's all a balancing act between individual freedom and society.

As a society we generally seem to be OK with allowing a few people to be hurt or killed in exchange for a type of entertainment. For example if you are a race car driver, you are certainly increasing your risk of dying, and increasing the risk of killing spectators or other people on the racetrack, but we accept that because it is entertaining. Now I think it is a problem if people are driving a Bugatti recklessly on the roads and endangering others who are just driving around, but I think you are just as dangerous in one of the many cars which can go almost 200 mph as you are in a car that can go 300mph, since it is pretty difficult to approach 200mph on a public road.

bugatti tends to only make <50 of each of its models, and many of them are driven rarely if ever. it's not "ok", but there are much more pressing concerns in the world of road safety. I've never even seen a bugatti in person.

To be honest, I'd be scared too in a 1991 Corvette. I wasn't even aware they could do this.

Today's cars do feel very different and much safer.

Living in a country where going 124mph+ is nothing special helps too.

> It's futile to actually have road-legal cars that go this fast

Bugattis are high-end collector's cars. The average Bugatti owner owns 84 cars, 3 jets, and a yacht:

https://jalopnik.com/the-average-bugatti-owner-has-three-jet...

You buy a Bugatti simply so you can say you have one.

No one decides to marry their spouse based on how punctual they are. Cars like these (and just sports cars in general) are things you buy with your heart

Not like you'd get anywhere any faster when there's traffic around. Punctuality is a sign of planning, and that's a desirable trait, so I don't know about no one.

People who are punctual tend to be reliable in general, so maybe it's not a bad idea?

> No one decides to marry their spouse based on how punctual they are.

Not their first spouse at least.

> No one decides to marry their spouse based on how punctual they are

Anecdote to the contrary: I've broken off a relationship with someone who was habitually very late, for that reason (and the denial that it was a problem).

One of the things that I really like about my current partner is that they are habitually very punctual, or early.

It is not futile. You can drive to a race track and have fun without having to rely on a trailer and another car.

Mmmmhmmm, don't really see it as an issue here given that not many folks are going to be buying a £2.5m hypercar to drive at three times the speedlimit to work on a Monday morning.

True, but that just makes the whole exercise even more pointless.

There's really no point in building a car that can go above 150km/h, but perhaps some of the aerodynamics can translate into more fuel efficient car.

I'm also slightly annoyed by the usage of the word "barrier". There's physical or perceived 300mph barrier. People have built cars that will go a super sonic speeds, so there was never any doubt that it would be possible. Admittedly it is a little funny that the Bugatti is faster than a Formula 1 car.

A lot of things humans do are pointless, but all the same we do them. Doesn't stop it being fun does it?

0-180 in the same time and hitting a speed limiter is going to be just as much fun for everyone. Unless you happen to have laid out a strip at Bonneville Salt flats. That seems poor justification.

I thought he meant that the design work was fun. The challenge. What is the point/justification of Olympic sports?

I'm talking about the challenge, building a car that can do 300mph and then also drive to the shops seems like a really difficult engineering task.

I know you are probably just speaking in jest but "faster" is all relative. If you put this Bugatti in an F1 race, it probably wouldn't win. They are both engineered to do their very specific things.

Just to put some numbers to that... at the Nordschliefe in 1974 Lauda dipped under 7 minutes. The original Veyron managed 7:40 in 2005. BMW engineers estimated their 2006 car could lap it in 5:15.

Basically, put a few corners in and I don't think it would even be close. There's quite a few cars that can claim a faster top speed than an F1 car though.

Going around 160km/h on highways in Europe is pretty common, also higher speeds for eg. in Germany

> Going around 160km/h on highways in Europe is pretty common

is it? That is 20-50km/h above the limit in all european countries other than Germany. There are people going that speed, but in my experience across a few countries 99% of the traffic does not go that much above the limit.

Sources:

https://ec.europa.eu/transport/road_safety/specialist/knowle.... https://autotraveler.ru/en/spravka/max-speed-limits-in-europ...

Have you ever been to Poland? The legal speed limit on the motorway is 140km/h, but 160km/h is more common, especially since there is effectively no fine for going that quickly, police are mostly interested in people going 200km/h+, because the fine for doing 160km/h would be like 100PLN(~$30/£20). I've driven my Mercedes-AMG some time ago through Germany and then through Poland, and yes, on the Autobahn I was able to hit 250-260km/h for maybe 4-5 minutes at the time(legally, which is amazing and I would 10/10 recommend to anyone who likes driving, scary as all hell though), but overal I can guarantee that my average speed was higher in Poland, the traffic is just moving a lot quicker and there's less roadworks compared to the autobahn.

From experience, in France there are stretches of motorway where you would simply fit in the fast lane traffic by going at 160km/h (and yes the speed limit is 130km/h and cars going that speed stay well on the right).

Last statistics I saw showed ~50% of all traffic (which includes vehicles with speed limiters) travel in excess of the 70mph motorway limit in the UK.

Personally, I tend to cruise at an indicated 100mph because above that enforcement ratchets up. Which is about 160kph. I certainly think it's fair to describe that as not uncommon. I do similar speeds in France and Germany and am rarely the fastest vehicle around.

> Personally, I tend to cruise at an indicated 100mph

In the UK? OK, at least it's clear what you think of the law.

Personally, I hope you get nailed for it. That sort of contempt for both the law and other road users ought to be penalised.

(Maybe you only cruise on empty motorways at 3 AM, and so that makes it acceptable...?)

When half of all traffic exceeds a limit I think it's in the wrong place.

As far as getting nailed goes, it would be a fixed penalty ticket, if anything. I don't agree that it's contempt for other road users, any more than it is to do that speed (or significantly more) on an autobahn.

In the US, I often drive in roads with a posted limit of 80mph going ~100mph, and even then I get passed sometimes. It's not inconsiderate to other road users if I make sure to pass and yield appropriately, though it's certainly a violation of the law.

And yeah, I think the law is stupid. I believe that we should eliminate speeding tickets and have police only enforce "reckless driving". Going the speed limit could be much more dangerous than exceeding it given traffic and road conditions. Going 2x the speed limit with no other cars in sight should be penalized much less than failing to signal when changing lanes while in traffic; the former only puts the driver and passengers at risk, while the latter risks all cars within a half mile or so if they cause a pileup.

Police seem to enforce the former far more than the latter because it's easier, not because it has the biggest impact.

That's basically how it works on the Isle of Mann.

I remember in my parents car a few years back, I was doing around an indicated 220km/h on a motorway in the UK. There was still things going faster than me.

This was on a relatively quiet, well sighted motorway in good conditions. But there were other people clearly in a hurry!

No it is not 130 is the general limit.

http://www.unecartedumonde.fr/wp-content/uploads/2014/05/car...

The speed limit is typically 130km/h, but depending on the country it may be pretty much ignored.

Useless does not equal pointless.

It sounds like you don't know about track days or drag strips. That's the way to enjoy a car that goes faster than 150km/h fully. A 300mph Bugatti is still way above any speed you'd reach, though.

Even in that case a much lighter (and cheaper!) car like an Atom or Caterham will be a lot more fun than one of these hulking great monstrosities. Often faster as well, depending on the track.

That's a matter of taste though - for some people, a smaller, lighter, weaker can is more "fun" than a car that is stupidly fast but only in a straight line. But then there are people who only care about that and that 0-60mph run is what does it for them, not tossing an MX-5 around on a twisty road.

Bugattis aren't meant for motorsport enthusiasts anyway. They are too expensive and complicated to be track day cars and an enthusiast would buy something more driver oriented rather than stats oriented.

You could definitely enjoy one on a track if you had one. But you would probably spend more time just enjoying the thought that you own it, keeping it safe, then you would take your actual track car to the track.

Yeah, I wrote the same thing in another response. But a few track days per year is a good way to have real fun in a supercar.

Launching an Atom or Caterham with big power is incredibly hard for most people, even for those who own them. Not really a drag strip car, more a club circuit vehicle.

> There's really no point in building a car that can go above 150km/h.

Even if you're "only" going to be driving at 160-180 km/h (as is common e.g. on the German autobahn) you want to be in a car that can do 220-240 km/h. You don't want to be 100% maxing the car out at your cruising speed.

It's a 300mph barrier for a road going car you could easily drive to your nearest supermarket if you so wanted.

I remember reading about a German chap who used a McLaren F1 for a commute on an unlimited section of the autobahn - his average speed was so high McLaren contacted him to check that everything was OK.

The F1, in pre-internet days, literally phoned home to McLaren with telemetry.

Edit: I think you had to physically plug it into a phone socket... in case anyone was being put off buying an F1 for security/privacy reasons. ;-)

Yeah the F1 had a modem that would phone home and give diagnostic and telemetry data.

I mean they obviously aren't doing this with the intention of having people actually take advantage of this speed on the road. The whole point is to build a vehicle which can go these kinds of speeds with the added constraint that you must be able to drive it on the road. Not everything people do or create has to be for purely practical purposes, that would be boring.

Correction: transmitting the track signal to the cab is how high-speed trains worked half a century ago. That's SOP on most modern trains by now, with high-speed rail using moving blocks now (no more physical signals at predefined distances, control system negotiates the safe distance for each train, based on realtime data).

I rented a car a couple of years ago that read speed signals and kept them in the dashboard for about 30 extra seconds. It was great usability. It only dealt with speed limitations and a couple of other signals, though - if it dealt correctly with “next exit” signs I would never buy a car without that system.

Bugatti and all supercar manufacturers are in the "futile" business.

> It's futile ....

But it is fun.

This got me thinking. Once I thought it was fun, but the more I look at it, the more I feel it is utterly pointless.

A racing car has a function: to get around a track faster than other cars (over a period of laps). To do this, it needs to be versatile: turning, braking, acceleration, fuel consumption, range of vision and suspension (among others) play a role. That's the true engineering challenge. It's why it has wheels, not wings. But to simply go fast, seems a bit pointless to me.

The pointlessness is kind of the point, along with a bit of juvenile thrill. These cars are a display of wealth and excess. You're telling the world you can afford this much power and don't need to worry about things like utility or efficiency, and maybe you'll just keep it in a garage or drive it around a track, but still you can have a car so powerful it's almost illegal and most people can't.

idk... I've always assumed that the pointlessness is in the playfulness: extending our boundaries, setting new rules. We value the daring, the boundless, the discoverers and the challengers. And I understand we connect a certain status to that and I also understand that certain people just want to be able to buy the status without putting in the time, knowledge and risk. But for me at least, this is so remote from and unconnected to the original challenge and thrill, that it becomes idiotic: pointless without even the playfulness.

Some people buy million dollar watches because they appreciate the craftsmanship and quality, some people buy them so you'll know just how much more valuable their time is than yours.

It's a status display in either case, given that one could adequately tell the time on a cheap digital Casio.

Yes, but there is an interesting difference between the two w.r.t. status.

Status is generally derived from the signaling of certain values. Wealth is one such value, but in general we assign status to a combination of values. Aesthetic + Wealth = Art. Strength + endurance = Athletics. Leadership + Vision + Knowledge + Intelligence = Innovation.

For me, at least, these super expensive cars have lost all signaling value, except 'wealth'. Because of that, I would almost call it tasteless, senseless and idiotic.

I think you're underestimating just how much engineering it actually takes to get a road-legal car to go this speed. Going fast in this case is just a different set of parameters to solve for, but no less of a challenge.

A car built for top speed is not the best choice on a race track but you don't need a purpose-built race car to have an occasional fun track day. Occasional because it's not cost-efficient to bring an unmodified sports car to a race track too often (brakes and tires will go quickly), as opposed to a dedicated track car, and at some point, even the fastest sports car will seem slow in turns and under braking. A car built for top speed should be exhilarating on a drag strip, though I doubt more than a few owners will go.

Fun is important because directing and motivating teams of humans is a difficult skill -- especially when you want to do things where the path forward is at all nebulous, like materials and design research.

Yes. Fun emerges due to sharing of similar goals. People have fun because they play the same game, enjoy the same movie or simply have the same freedoms. I agree that it helps direct and motivate us. (Thanks for that insight!)

I guess I just cannot share in the purpose of the team making this car go +300 mph. We already have the Thrust SSC (1228 km/h / 763 mph). So what does this prove? That if you want to take corners and need to see what happens behind you, you won't get to go that fast? Why not productionize the Thrust SSC then?

Max speed (to me) is just a senseless metric. It's a bit like clock speed of a CPU. Interesting metric, but only in relationship to other factors.

By that logic a top fuel dragster is pointless? For some racing is something that happens in a straight line, for others it involve turns - neither serves a purpose in the grand scheme of things and can be considered "pointless".

No, because a dragster has a specific function. It is a perfect counter-example to the senseless: 'look how fast our super-car can go.' There are many more values involved in dragster racing: knowledge, innovation, joy, creativity, competition, determinism, meaning, enthusiasm and playfulness. And it is all related to a singular goal: getting over the finish line faster than the competition.

But with such a super car, idk, I'm just left with an empty feeling: why? What is the point?

But all of them have various constraints, a formula so to speak, that they must adhere to. A specific function within that world of constraints.

The Bugatti is a street legal car designed to shatter speed records in a straight line. If that isn't specific function with a formula I don't know what qualifies. The street legal part of a super car is not inherently different than the 1.6L FI hybrid engine regulations of Formula 1, it's just a different set of constraints.

You do not create a winning street legal super car without knowledge, innovation, creativity, determinism, enthusiasm - and by proxy of those joy, competition, and playfulness.

I simply do not understand the gate keeping here. If it's not your thing, fair enough. But please do not invalidate the joy of others because it is real to them.

It's comparable to an mechanical watch. You can make a digital watch significantly better at time keeping and all the other functions, that is substantially cheaper both to produce and maintain. But if mechanical precision devices make your world go around, then I can appreciate that - I'm just not going to pay $10k yearly to maintain an elaborate mechanical wristwatch.

The speed is basically an excuse for an expensive car. Due to reasons (which I don't want to delve into) there are people who can and want to spend an absurd amount of money on a car, but if you just give them a perfectly fine people mover with more "gold and eagles" (sorry for the futurama reference), they'd feel ripped off. The car has to offer something that a less expensive car can't and that's where paper speed comes in. Even perfectly irrational purchases require some element of rationality.

PS: if you just want the joy of speed, the fix is not a faster car but a vehicle that allows you to experience the speed better, one that isolates you less from the road. A light roadster, a motorcycle, a roadbike (quite a few people actually "graduate" from a motorcycle to a roadbike because perceived speed is higher in lycra and with legs doubling as shock absorbers)

Even if it could be operated safely by a person, it still would have no practical value. This is not a transport feat, it's an engineering/brand feat.

I love engineering feats.

How is it not practical? We have race tracks in my area, so if I owned one of these, I'd get a ton of use out of it destroying other people on the track. That's pretty practical from my perspective.

It's not going to make my commute any faster, but that's not the only use for cars.

"destroying other people on the track." this isnt practical.

also, tracks have turns and this thing weights like 2 tons so good luck with that.

140mph -> 225 km/h 125mph -> 201 km/h When converted I understand the high speed you talk about. The TGV go at 300km/h.

It’s futile to have quad-core laptops bought by managers who barely run office apps. But the world of commerce runs on dreams.

Quad core is entry level now, when did you last buy a laptop :-)

Having a laptop with say a 16/32 Ryzen 3 (which believe is due fairly soon) would be pointless

> "Quad core is entry level now, when did you last buy a laptop :-)"

It may be entry level, but it's also overkill for what the vast majority of people need their laptop for.

But it does help drive demand for advanced in computing power, which helps drive prices down for the computing power engineers need.

Not sure Engineers are concerned with laptop power that's just a client.

There is no such thing as too much IPC, Primary memory, and Backing store - this has been true since WW2 when Colossus was state of the art.

There Is such a thing as to little budget :-(

But its mostly people using bloated software that need those fast computers...i just need a shell n ssh client...

I drive a nice looking car and get asked almost daily how fast it goes or how expensive it is or how much power it has. Bugatti is on point bringing out all the big numbers because that's what all the non-car-guys want to know! Who cares about practicality when you can be the guy that owns the car that makes all the dudes brag to their friends that they spotted a car that can go x miles per hour etc.

On the other hand, if I get asked those questions, I have to judge the person asking and do some calculus in my head to determine if I can get away with lying that it goes 200mph or costs 200k despite not even coming close to reaching those numbers. Or respond with another impressive factoid they can go home and brag about when I don't want to reveal my wealth or my lack of it. Bugatti owners don't have that problem!

You don't have to drive road legal cars 300mph on a street. That's why they have streetcar races at racetracks. Also, I'm very much doubting that any Bugatti owner bought because it's in any way a practical purchase.

> The "obvious" upgrade ...

What's stopping the trains from operating autonomously?

Drivers are still a lot better at spotting pedestrians on tracks than autonomous systems. Autonomous train systems already exists, but those are completely enclosed systems, like a city metro system. Not a system where speeds reach 200 km/h, or even 100 km/h.

Modern rail can (and does) run autonomously, at 160 km/h. How-e-ver, it can run autonomously about 90% of the time...and it's far, far more cost-efficient to keep a driver in the cab than to add reliability nines here: detecting and reacting to humans is far harder for machines than for humans (think Elaine Herzberg, but at 160 km/h).

The ability to spot pedestrians on tracks is something you want to avoid.

First you cannot break it anyway that fast. Second, rolling over suicidal pedestrians has a high psychotherapy cost. Driver-less trains not.

Unions, mostly. The tech is there, especially on a 100% grade separated line like the TGV - no road crossings, and the full length is either fenced, in tunnels, or on bridges.

That's true of attempts to remove the guard, but I don't think it's true of automating the driver.

Automatic train operation systems are expensive to design and maintain, and their advantage is mainly in precision: if you're trying to put 30 trains an hour down a segment of tube tunnel, it's very helpful if the system reacts immediately to red signals and brakes at a constant predictable rate.

For longer distance services, not only is the cost of fitting ATO equipment to the track much higher (as the routes are much longer), but the schedules don't need such precise operation. It is probably cheaper to retain drivers.

In practice, even most metro systems with automatic train control still have someone on the train: it's important in an emergency and if there are degraded conditions or unusual operating needs it's helpful to have someone trained to take over.

Japan and Australia both have some GoA 4 systems. There may be no employees of the operator on the train at all when it's operating. I'm sure there are or will be more of these systems (as you say, for metro services which can be grade separated and run with high service frequency) over time.

In a GoA (Grade of Automation) 4 system the intent is that if things go wrong the remote team operates the train. This obviously means it can't cope with power failure, but these are invariably electric trains so they aren't going anywhere without power anyway. A mechanical fault that renders the train unable to continue safely under its own local supervision would result in a remote operator controlling it though.

They do in a lot of metros, although it's often very hard to retro-fit. The DLR got it at build-time. [1]

One of the big issues is 'degraded working' where there's been some sort of failure (or perhaps adverse weather conditions) which means trains have to operate on vocal authority to proceed on sight. The problem then becomes as hard as driverless cars - you have to know when you've reached milepost 70 or the next set of points by sight and it's really bad if you miss them. Arrival to and dispatch from stations without platform-edge doors is also tricky and human staff are often required to manage the process.

[1] https://en.wikipedia.org/wiki/Docklands_Light_Railway

Very good point with the degraded working. In a train serving hundreds of passengers (or many dozens of truckloads), running on something that is literally as expensive to maintain as a whole rail network, the cost saved by cutting the driver is just not worth the extra hassle and delay in edge cases. Perhaps it is much more meaningful to think of that person as the engineer on duty than as a driver.

Autonomous rail has probably racked up billions of passenger-kilometres by now. The edge cases are pretty thin and it's unlikely that a human driver will have equivalent levels of accumulated experience.

The most reliable line in the MTA, for example, is the L train. It is also the closest to fully autonomous (due to union rules, there is a driver who turns it on and then "supervises" the train).

I use a driverless subway almost daily. And it's rare, but not not terribly rare to see the fallback driver panel in use. It works because a fallback driver can be deployed in minutes, which is very much not true with the distances spanned by heavy rail.

Regarding the L train, how much would service suffer if the "supervisor" wasn't there to clean up whatever is left by reliability nines? We may never know. And it is hardly surprising that a recently modernized line is beating the living history museum that is the rest of the MTA. It's quite a leap to go from modernization causing reliability to automation causing reliability.

Every improvement made of expensive cars luxury or sports ones were eventually adapted to cheaper cars.

The ABS is one of those examples https://en.wikipedia.org/wiki/Anti-lock_braking_system#Moder...

Will their owner often if ever use them at their full potential? Probably not but if they can afford it, who cares?

As long as the research can be funded through it.

Sometimes, things don't have to really make sense for people to love it.

I wonder how well their next model would sell if it was limited (with no option or upgrade to unlock it) to a maximum of 100mph. I imagine most buyers aren't buying to race it around a track.

A train going faster than 25mph or so is already too fast for the operator to react (braking distances are huge!), so I doubt that the top speed is limited for that reason.

The driver can't usefully brake in response to a person on the track, but they do need to be able to brake in response to a trackside signal. At 140mph, braking distances are greater than sighting distances - by the time you've seen a signal, it's too late to stop. That's catastrophic in a fixed-block signalling system, which can only detect the presence or absence of a train in a particular signalling block; if you end up with two trains in the same block, you've got to run the whole line at a crawl to restore safe separation distances between trains.

High speed trains universally use moving-block signalling with in-cab signal indication; rather than relying on fixed trackside signal lights, the signalling system constantly tracks the exact location of each train, creates a virtual signal block around that train and indicates signal aspects and line speeds to the driver on a display in the driving cab.

https://en.wikipedia.org/wiki/Railway_signalling#Fixed_block

Just a small nit: almost all high-speed systems still use fixed block signalling, but with in-cab signal indications as you say to give more warning time (and a constant reminder rather than having to spot a signal as it goes by in a flash). Moving block turns out to be much harder to implement than expected; it's included in the European Train Control System's level 3, but even most new installations are of level 2 (fixed block with in-cab signalling).

Just because the train can’t be stopped doesn’t mean there is no point. Much better to hit something at 50 rather than 70.

Do not underestimate E=mv^2 ; hitting something at half the speed means quarter of the energy. Case in point: at a speed of 135 km/h, driver sees a bridge falling across the tracks half a km ahead, engages brakes, hits bridge at 90 km/h. By reducing the speed by 1/3, the total energy of the impact was reduced over 50%. There were 6 dead in that crash; without braking, the entire train plus 400 pax would have been blown to bits. https://en.wikipedia.org/wiki/2008_Stud%C3%A9nka_train_wreck

The obvious upgrade is to have no operator at all. It boggles the mind that we're seriously talking about self-driving cars on shared roads, and at the same time don't have self-driving trains, and instead allow them to fly off the rails every year due to operator error.

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