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Re:I Got a 'Mild' Breakthrough Case by pandaman on Sunday September 12, 2021 @06:05PM (#28505470)
Why would you want to pull the handbrake in a turn while going 50 mph? And what is going to happen if you pull the handbrake at 50 mph other than the handbrake burning out? I have not had a car with a handbrake at all but I drove a few rentals with one and they drove normally even when I forgot to take them off the handbrake, the thing is just a lever with a wire, it cannot stop the car even on idle. Or do they use a rally car with a hydraulic handbrake that does something at that speed?
Re:I Got a 'Mild' Breakthrough Case by nradov on Sunday September 12, 2021 @06:54PM (#28505813)
The point of pulling the handbrake is to artificially trigger a slide in a controlled environment in order to verify that the student driver has the vehicle control skills necessary to recover. It's similar to what can happen driving on ice.
Re:I Got a 'Mild' Breakthrough Case by pandaman on Sunday September 12, 2021 @07:29PM (#28506119)
So the car is supposed to slide when you pull the handbrake? This will be hard to pull off in the US where most cars have an electronic parking brake and the ones that have the actual lever have it connected to a weak drum brake that cannot lock wheels when the engine is running.

Also, the whole test seems to be set up like a gold rush for lawyers - if you actually managed to slide the car and roll over at 50 mph you are almost certain to have some injuries not to mention the damage to the car. Who is liable for those, the government that ordered the driver to execute a dangerous maneuver in order to obtain a driving license? What if the driver dies from the injuries?

Re:I Got a 'Mild' Breakthrough Case by jjav on Monday September 13, 2021 @12:42AM (#28507922)
> So the car is supposed to slide when you pull the handbrake?

Yes, that's what will happen if you brake the rear wheels (what the handbrake does) in a turn.

The point isn't that you'd ever do that, of course, but to simulate the rear end of the car sliding which can happen if you hit ice, oil or even uneven water patches. Can you control that slide? It's really awesome if Denmark is including car control in the test. The US should do the same.

I strongly encourage you (everyone) to find a car control clinic in your area and participate. Even a single weekend will raise your car control skills significantly if you've never had any instruction before.

Newer cars have a lot of traction control magic that try to save you and often do, but there's still no substitute for the driver having skills as well.

Sure the DMV manual will tell you to steer into the skid, but there's no way to learn this muscle memory without practice and the most productive practice is with a good instructor.

(I used to instruct the BMW club car control clinics (open to all cars) before life got too busy, hopefully will take it up again in the future.)

> Also, the whole test seems to be set up like a gold rush for lawyers

OP said this was in Denmark, so presumably every little thing isn't a "gold rush for lawyers" unlike in the USA.

Re:I Got a 'Mild' Breakthrough Case by pandaman on Monday September 13, 2021 @12:55AM (#28507982)
Handbrakes do not always break rear wheels for one, some cars have front parking breaks. I am pretty sure you will be off the road if you locked your front wheels in a turn no matter how much muscle memory you have, you cannot steer with locked wheels.

And I have not seen a car where a handbrake could lock wheels even on idle, least on driving in gear at 50 mph. I don't doubt such breaks exist, rally cars supposed to have them, but on my car, for instance, all that is going to happen if I pull the handbrake flap in gear is nothing and if I hold it for 5 seconds it will do an emergency stop using its ESC,ABS and all kinds of smart technology (I think it's also supposed to move to the shoulder and turn on hazards but I never really tried it). It won't slide for sure. How am I supposed to pass a test like that? Rent a 500K rally car?

>OP said this was in Denmark, so presumably every little thing isn't a "gold rush for lawyers" unlike in the USA

People can just kill themselves on orders from government in Denmark? Sounds like the country not to take as an example to me.

Re:I Got a 'Mild' Breakthrough Case by oynqr on Monday September 13, 2021 @01:57AM (#28508244)
Even if you could not lock the rear wheels on a regular manual car with the handbrake, these cars are always modified for instructive use. Think additional mirrors/pedals for the passenger.

An upgraded handbrake doesn't seem far-fetched.

Re:I Got a 'Mild' Breakthrough Case by jjav on Monday September 13, 2021 @02:10AM (#28508299)
> Even if you could not lock the rear wheels on a regular manual car with the handbrake

Mind you, you don't need to lock the rear wheels to induce oversteer (rear sliding out).

All you need to do is to make the rear wheel braking force be higher than the front wheel braking force while turning. Which in this case, since there is zero braking force on the front wheels, doesn't take much at all. A very quick pull on the handbrake will do it.

If you ever drive a race car with an adjustable brake bias control (changes percentage of braking force front/rear) it's easy to experience it doesn't take much rear bias to induce a spin if braking in a turn, even though none of the wheels ever lock.

Re:I Got a 'Mild' Breakthrough Case by pandaman on Monday September 13, 2021 @08:50AM (#28510849)
So every time I drove off with the engaged parking brake I had my car sliding in the turns? Great news: I appear to have so much muscle memory that I was able to drive without even noticing that.
Re:I Got a 'Mild' Breakthrough Case by pandaman on Monday September 13, 2021 @08:28AM (#28510606)
So you use an instructor car's to pass the driving test in Denmark? It's not how the things in the US work. People cry bloody murder if a state requires to show ID to vote because of unmanageable costs of getting a 20ish dollar/5ish years ID, imagine you had to rent a specially modified car to get a DL or not being able to get a job/buy food?
Re:I Got a 'Mild' Breakthrough Case by jjav on Monday September 13, 2021 @01:47AM (#28508202)
> Handbrakes do not always break rear wheels for one, some cars have front parking breaks.

Which one specifically? I've never encountered one and a brief web search didn't find any. I'm sure it can exist, but seems exceedingly rare at best.

I mean this in the most encouraging way possible: your comments (this and previous) suggest you have zero experience with car control. I greatly encourage you to find and participate in a few car control clinics to see how cars actually behave on the edge of adhesion and beyond. It's a great learning experience and also just fun. Most importantly, if you ever do hit ice/oil/etc, it might just save you from a crash.

> People can just kill themselves on orders from government in Denmark?

No need to be silly. Surely these tests are done in a suitable location, and there's zero risk from a bit of a slide or spin. Again, something you could experience and learn in a car control class so it stops becoming scary.

Re:I Got a 'Mild' Breakthrough Case by herbstein on Monday September 13, 2021 @06:07PM (#28517517)
Coming back in late here.

> No need to be silly. Surely these tests are done in a suitable location

My tests were done in the middle of a former cold war airstrip. This link should show the complex in a satellite view: https://www.google.com/maps/place/K%C3%B8reteknisk+Anl%C3%A6...

Notice the darker patch of tarmac. That is extra-slippery when wet and has a sprinkler system on the grass next to it.

Re:I Got a 'Mild' Breakthrough Case by pandaman on Monday September 13, 2021 @08:23AM (#28510562)
Wiki article on the handbrake points at the brands, also ZF makes this https://press.zf.com/press/en/media/media_15682.html not for the parts collectors I imagine. It is hard to check parking brake locations on the cars via internet though.

And thanks for your concern about my car control, you don't seem to be talking about the things I mentioned though: the lack of parking brakes on many cars and the lack of parking brake capable to lock wheels on many more. I am not going to go to your clinic anyways so if you don't want to talk on the topic I will bow out.

Besides, you just informed me that spinning out is completely safe and won't harm me so why again I need to train for that?

Re:I Got a 'Mild' Breakthrough Case by jjav on Monday September 13, 2021 @04:31PM (#28516486)
So there's about 4 cars with front parking brake based on wikipedia, all of them very old and esoteric. They are so rare they can be ignored as outliers. If you show up at the driving test in one of those I guess you'll have to rent another car.

> Besides, you just informed me that spinning out is completely safe and won't harm me so why again I need to train for that?

You're not discussing in good faith so I won't continue.

Spinning out in a training facility (generally a large parking lot) is perfectly safe, it's a training area. Spinning out in traffic on a windy road, not so much. That's why you should train first in a safe space with instructors, before driving on public roads.

Re:I Got a 'Mild' Breakthrough Case by pandaman on Monday September 13, 2021 @05:55PM (#28517381)
4 car brands, each brand makes multiple car models, Citoën is by no means a rare make. I've seen them even in the US and in Europe (where Denmark is with its test) it's one of the popular brands

Spinning out at 50 mph is not safe anywhere as you can easily rollover, I pity people who go into your clinic as you don't seem to have a slightest clue.