Break Failure/Cut Breaks(Hypothetical)

[Rater202]

In movies, whenever someone's breaks fail or they find out their breaks have been cut mid-drive, it always seems like the car keeps going at the same speed, or speeds up, even when it's not going down a slope, and only stops when the car hits something.

And I always wonder why they don't take their foot off the gas pedal. It always seems like as soon as they realize that the breaks aren't working, they lfoor it.

But I know diddly squat about cars, so...

In real life, you'd take your foot off the accelerator and try to steer the vehicle away from anything you don't want to hit. Right?

Is there some science or engineering reason why a car with cut breaks would keep going in a straight line at top speed till it hit something? Or is this just Hollywood depicting people as morons for the sake of drama.

[Telok]

Hollywood.

IRL what you do will depend on the age of the car and if it's manual or automatic transmission. Manual trans can downshift to use engine braking or just go into neutral and use the hand brake. Older automatics can shift into neutral and apply the hand brake as well. Some of the more modern cars I've driven seem to try to mostly maintain speed and only gradually slow down with no pressure on the accelerator. I have no idea how the computers are set to respond to no accelerator + brake + not slowing down fast enough. Not sure if you can still shift into neutral at speed either. In theory the hand brake should still be fully manual, but I've run across a couple Fords that would drive fine (just not accelerate as fast) with the hand brake fully engaged.

[Peelee]

Hollywood.

IRL what you do will depend on the age of the car and if it's manual or automatic transmission. Manual trans can downshift to use engine braking or just go into neutral and use the hand brake. Older automatics can shift into neutral and apply the hand brake as well. Some of the more modern cars I've driven seem to try to mostly maintain speed and only gradually slow down with no pressure on the accelerator. I have no idea how the computers are set to respond to no accelerator + brake + not slowing down fast enough. Not sure if you can still shift into neutral at speed either. In theory the hand brake should still be fully manual, but I've run across a couple Fords that would drive fine (just not accelerate as fast) with the hand brake fully engaged.

Older automatics can also downshift, IIRC. It's only the newer ones that just have a single D.

Probably using "downshift" incorrectly here, but the D3 and D2 gears are what I'm referring to.

ETA: Also, for the OP, even at neutral, it would take a while to slow down - longer than most shots of cars in movies or TV shows typically have before they crash or whatever else happens. It's not a "making people look like idiots" thing at all

[warty goblin]

Having once ended up driving a pickup without brakes (down a very steep and twisty gravel road) you pretty much just don't accelerate and steer as normal. Stopping at the bottom was a bit of an adventure, but there was a tiny amount of brake left if you grabbed the wheel with both hands, lifted yourself out of the seat, braced your shoulders against the seat, and stomped all the way down. So that was fun.

[DeadMech]

Having once ended up driving a pickup without brakes (down a very steep and twisty gravel road) you pretty much just don't accelerate and steer as normal. Stopping at the bottom was a bit of an adventure, but there was a tiny amount of brake left if you grabbed the wheel with both hands, lifted yourself out of the seat, braced your shoulders against the seat, and stomped all the way down. So that was fun.

I had something similar. Was travelling down main street in my old car just about to turn off into a gas station. Suddenly the engine died. Turns out power brakes and steering make controlling a vehicle just slightly easier. Cause suddenly I too was standing as far as my seatbelt allowed and wrenching the wheel as hard as I could so that I wouldn't continue straight into their sign advertising the price. Luckily no pedestrians or other vehicles were in my way.

[Telok]

ETA: Also, for the OP, even at neutral, it would take a while to slow down - longer than most shots of cars in movies or TV shows typically have before they crash or whatever else happens. It's not a "making people look like idiots" thing at all

Momentum is physics is a bitch. You can cheat but don't get caught.

Yeah, those nice efficent greased bearings to cut down on friction so the wheels can roll makes hoping to use to use wind resistance and rolling friction to slow down... not a good plan. It's been years, but I still miss my old manual go-cart with it's hard pull "thou shall not anything" hand brake.

I should look up the specs on our current car.

[Radar]

Hollywood.

IRL what you do will depend on the age of the car and if it's manual or automatic transmission. Manual trans can downshift to use engine braking or just go into neutral and use the hand brake. Older automatics can shift into neutral and apply the hand brake as well. Some of the more modern cars I've driven seem to try to mostly maintain speed and only gradually slow down with no pressure on the accelerator. I have no idea how the computers are set to respond to no accelerator + brake + not slowing down fast enough. Not sure if you can still shift into neutral at speed either. In theory the hand brake should still be fully manual, but I've run across a couple Fords that would drive fine (just not accelerate as fast) with the hand brake fully engaged.

Just one more reason to stick to manual transmission. Without brakes, using the engine braking is the most important technique. Hand brake might be stronger, but it is not designed to be used at speed, so it has a tendency to overheat and break. So if possible, slow down with the engine and apply hand brake in emergency or when you are reasonably slow.

[Peelee]

Just one more reason to stick to manual transmission.

I'll accept the risk of less control if someone cuts my brakes so long as I don't have to learn how to drive stick. I can't even bring myself to learn how to use Dvorak, which would significantly improve my life, so learning to drive standard ain't in the cards.

[Grey_Wolf_c]

I'll accept the risk of less control if someone cuts my brakes so long as I don't have to learn how to drive stick. I can't even bring myself to learn how to use Dvorak, which would significantly improve my life, so learning to drive standard ain't in the cards.

Nice thing about electric cars: they don't use, or need, gears. So the discussion over which approach is "better" might soon(ish) be as obsolete as blowing up fossil fuels 2000 times per minute to power our vehicles.

GW

[Peelee]

Nice thing about electric cars: they don't use, or need, gears. So the discussion over which approach is "better" might soon(ish) be as obsolete as blowing up fossil fuels 2000 times per minute to power our vehicles.

GW

As if I needed another reason to want one.

[JeenLeen]

Here's a story about a possible solution. Automatic transmission car.
Short version: shift it to neutral or turn on the emergency break.

I had a scary thing happen once. Driving a car, and the breaks stopped working. I think maybe even it acted like I was keeping my foot on the gas when I wasn't--like, taking my foot off the gas didn't make the car start slowly decreasing in speed. Not accelerating, but it stayed steady, as if the cruise control was on. (But I never used cruise control back then, so quite sure it wasn't.)
I kept relatively cool. Fortunately, I was on the interstate during a low-traffic hour, so no need to worry about running stop signs or red lights. Eventually I stopped it by (I forget which) turning on the emergency break OR shifting the car to neutral. I think it was the latter, since the damage to the car was minimal. Once in neutral, I was able to stop.

To my surprise, my mechanic couldn't find anything wrong with it. I wound up selling it about a year later to someone, and he totaled it (for unrelated reasons) a week or two later. I think, later, I heard about a recall on that vehicle about the issue, but it was long after I had sold the car. (And I think I only paid like $2000 for it used anyhow, so, like, bad in that it was a life-threatening hazard that might've happened again at any time, but meh in that it didn't happen again.)

[warty goblin]

I'll accept the risk of less control if someone cuts my brakes so long as I don't have to learn how to drive stick. I can't even bring myself to learn how to use Dvorak, which would significantly improve my life, so learning to drive standard ain't in the cards.

Stick has some advantages besides brake problems. Because you have manual control, you can for instance use very carefully timed shifts to rock a car out of a snowbank. Also dead useful for pulling or hauling things, since you can keep the engine in a low gear for more torque. It's not really very hard to learn either, unless you're doing something like the above, you accelerate until the engine is doing about 3, 3.5 thousand RPM, take your foot off the gas, step on the clutch, shift to the next gear, then disengage the clutch while reengaging the gas. Only tricky part is that pretty much every manual transmission is a bit different, so you gotta learn every car's quirks. Generally once you know one stick, this takes all of ten minutes.


Now for a really fun manual transmission experience, there was our old Case tractor. I remember driving that thing when I was ten or so, and it took literally all my weight and strength to get the clutch pushed all the way in. Fortunately with tractors you pretty much just pick the fastest gear the terrain can handle/has enough power left over for whatever you're doing, fine tune with the throttle a bit, and leave it there.

[veti]

I had my brakes fail on a motorway once. Fortunately it was in a traffic jam, so I was only going dead slow anyway, so the handbrake was enough to keep me safe. But it gave me some nasty minutes, while I looked for a chance to get to a mechanic.

In an automatic - yeah, it would definitely be much worse. Thinking about it, I'd probably try engaging the cruise control, then rapidly reducing the set speed on that, but that assumes plenty of time to deal with it.

[Storm_Of_Snow]

I guess the absolute last option is switching off the ignition - and I mean the last option because the wheels will lock and (depending on the car) the steering lock will engage, although you might be able to disengage that again without restarting the engine.

Stick has some advantages besides brake problems. Because you have manual control, you can for instance use very carefully timed shifts to rock a car out of a snowbank. Also dead useful for pulling or hauling things, since you can keep the engine in a low gear for more torque. It's not really very hard to learn either, unless you're doing something like the above, you accelerate until the engine is doing about 3, 3.5 thousand RPM, take your foot off the gas, step on the clutch, shift to the next gear, then disengage the clutch while reengaging the gas. Only tricky part is that pretty much every manual transmission is a bit different, so you gotta learn every car's quirks. Generally once you know one stick, this takes all of ten minutes.

Or low revs in a higher gear for fuel efficiency, especially if you're in steady flowing traffic and don't plan on accelerating any time soon. And being able to select the gears yourself rather than relying on the car to pick the best one can help with conditions like snow and ice.

Now for a really fun manual transmission experience, there was our old Case tractor. I remember driving that thing when I was ten or so, and it took literally all my weight and strength to get the clutch pushed all the way in. Fortunately with tractors you pretty much just pick the fastest gear the terrain can handle/has enough power left over for whatever you're doing, fine tune with the throttle a bit, and leave it there.

Double-declutching on old/crash box transmissions (or if the synchromesh fails) - clutch down, come out of gear, clutch up, use accelerator to set the revs for the next gear, clutch down, into the new gear, clutch up again, and hope all the moving bits are still where they should be rather than in pieces at the bottom of the gearbox.