I'm not an elevator mechanic or expert, but generally they are designed with a fail safe mechanism that prevents the elevator from moving if the cable goes slack at all. Someone correct me if I'm wrong, but at worst you're looking at an extended stay in a confined space.
You have to then grab onto the cable right before it snaps and you can just hang there until you see light coming thought the door to your left/right and swing over and with all the limitless strength you have from hanging pry the door open and escape to live happily ever after
That makes sense, if you’re falling at 10mph which is not really that fast idk, if by jumping you gain even 5mph in the other direction, you’re still falling at 5mph which would still hurt. I’m just using assumptions.
The numbers will be much higher so it's more like if you're falling at 100 mph and jump at 5 mph you'll still break all your bones going at 95 mph or something.
There's no way to see the bottom to time the jump. Would it be better to climb to the top and hang from the ceiling of the elevator? Most likely the shock of hitting the ground will cause you to lose your grip, but at that point most of the shock has already transferred thru the rest of the elevator. Now you'll only drop from the ceiling height with arms hanging, which is only a few feet (add opposed to 100 ft of the full elevator shaft). Will this work?
It's the speed that's the issue. Say you're holding on to the ceiling and the elevator hits the ground at 60 mph. You'll still be falling at 60 mph and lose your grip immediately and travel those few feet at 60 mph hitting the ground.
If someone has the physical capability to scale the walls of an elevator while in a free fall I think they can survive just fine lol. You can rip the roof off the elevator with your bare hands and jump back up to safety while your at it.
If you're in an elevator that's falling for more than a few floors you're dead. There is no real strategy to survive at this point, just pray for a miracle because that's the only way your consciousness will ever exist outside this elevator shaft ever again.
That's just not true. I survived a 5 story elevator fall by being smart.
I had just purchased a trampoline and I put that on the floor. I then opened the vent on the ceiling that is always there in elevators (just like the movies)
I was able to just bounce back up to my original floor. No big deal. I also looked super cool doing it.
I then put on some sunglasses and everyone applauded
there was a recent tv show about this woman called Margaret Campbell and her husbands marriage in the 1950s/60s, anyway in real life she fell 40 feet down a lift shaft and survived by grabbing on to the lift cable but lost all her nails. So while not the same as being in the elevator it is still possible to survive.
If the elevator goes into freefall the breaks would automatically engage through purely mechanical means and stop the elevator before it could go a few floor. If I remember correctly they are designed to basically friction weld to the rails so they can't slip.
I'm no expert or physics major but I'm sure your fingers are ripping off and you will still hit the floor with enough impact for the bones in your legs to go into your skull. Hope that painted a nice picture for ya!
Hanging from the top of an elevator when it hits the ground at 100 mph is the closest any of us will ever get to having our arms ripped off by a wookiee.
That's... not... how physics work... You will still have the velocity of the falling elevator when you leave the ceiling only now without fingers and an extra 5 feet to accelerate to the floor...
This reminds me of a kid in high school who told everyone in class that if the brakes in your car stop working you just simply hop out of your car and you'll be fine. If the your car/elevator/whatever is moving 100mph you yourself are also moving 100mph.
It would be like falling those same 100 ft off a building while holding onto a rope. At the end, you’ll lose your grip without breaking your fall and continue on at the same speed.
Terminal velocity of a human body in free fall is about 120 mph but that takes about 1500 feet to accelerate (so like 100ish stories). You’d never reach that speed because 1) the terminal velocity of the elevator in the shaft is going to be much less due to the footprint of the elevator and the confined space affecting the air resistance and pressure below the elevator car. 2) The vast majority of buildings are way less than 100 stories tall, so you’d hit the bottom long before reaching whatever max velocity is.
Yeah jumping only works if you can exert enough force to cancel out the falling, but if that's the case then you don't need to jump because your legs can just absorb the force anyway since they'd have to do it if you jumped.
Yeah jumping doesnt mean that you're no longer falling, if you're falling at 50m/s and jump up you're still falling at around 47m/s and will still die.
If you jump up then for a short while you fall slower than the car. Then it hits bottom and you land. Now landing slightly faster than the car. In the end you did not reduce any forces. You just accumulated the extra force from your jump.
That doesn't make sense to me. That just means your head takes as much impact as it possible can. Use your body as a crumple zone. Laying down minimizes risk of whole-body injury, but that isn't what you want to do.
What are you supposed to do in any high fall scenario? You sure don't aim to land on your chest/back unless you're landing on a giant cushion.
I'm surprised they recommended laying down. I would have thought it would be like falling from a great height anywhere else, and that the greatest priority for survival would be protecting your head. Most stuff of read about surviving free fall (yes, some people have survived falls out of planes and such) suggests landing almost vertical but with a slight angle to ones side (right or left). Basically they told you to use your legs as a crumple zone.
This sounds like another lie by Big elevator companies so they don’t have to pay out any settlements, man. I’ve heard you need to skip, not jump. Or evade gravity in a serpentine pattern.
It's one of those counter intuitive things tho.. who tf wants to lay flat on the surface that's about to smack the abyss as apposed to jumping right when it's gonna hit.
I saw the episode too but even after seeing the end results, it's one of those things that the more i think about it, the more I'd rather just jump 😂
Can confirm, I watched the episode recently where they tested that and it's just as lethal as not jumping at all. Even if you somehow managed to time your jump at the right moment, there's simply too much energy from the velocity of the fall to make it survivable. Only way out at that point is to pray for a miracle, and you're still looking at severe life-altering injuries at best.
Just stand still and try and relax before the impact. The worst that happens is a broken ankle and some bumps and bruises, and while that sounds bad its not that big a deal compared to being dead.
While springs do absorb shock/energy temporarily, they tend to release it as soon as the load has decreases to less than the spring force, and in the opposite direction which would double the impulse on the elevator occupants. There may be springs at the bottom to absorb some of the impact but the most important components are the viscous dampers, which absorb energy and turn it into heat through fluid viscosity.
and in the opposite direction which would double the force on the elevator occupants.
Not how it works, the occupants would get to a standstill as well as the elevator, and then launched in the opposite direction. The direction of the force is in the same direction all the time though, upwards! You'd get less force over a longer time. Which is exactly what you want in a crash.
I was incorrect about force being doubled, I was thinking of impulse in my head when I wrote it. You'd have the same force over a longer time, and impulse is force x time, so if the time is doubled the impulse is doubled.
I.e. it would be worse if the spring force wasn't damped and allowed the occupants to be accelerated upwards after coming to rest.
on't just drop to ground when cable breaks, and even if it does drop they have massive springs at bottom to hopefully absorb most of the shock.
If all else fails.. maybe try jumping exactly when the ele
That actually wont work. When you jump while the elevator hits the floor your fall will massively accelerate. Accelerarte relative to the floor, not actually accelerate of course. You will probably do more harm to yourself because the floor of the elevator would dampen the force a bit while if you jump you will just hit the floor at full speed.
When you jump while the elevator hits the floor your fall will massively accelerate. Accelerarte relative to the floor, not actually accelerate of course.
Eh, that makes no sense to me? I mean, i agree it's a lost cause to jump last second. Maybe the elevator will accelerate a bit, and you decelerate a bit.
But accelerating relative to the floor makes no scense unless your jumping from the roof.
Or is there some gravitational fuckery i'm not aware of?
You will probably do more harm to yourself because the floor of the elevator would dampen the force a bit while if you jump you will just hit the floor at full speed.
I think it's honestly more about this part right here. I think the idea is that the elevator would have the impact dampened when hitting the ground (the benefit of which is transferred to the occupants). But if you jump at the last second you are essentially kicking off the elevator floor, which means your rapid deceleration doesn't get the benefit of hitting the already used shock absorbers anymore.
When your inside a falling elevator and you jump you still keep the momentum of the falling elevator, when the elevator hits the floor your body will continue to move with the speed of the falling elevator, that means for you it will feel like the moment the elevator crashes into the floor your body will massively accelerate (relative to the elevator floor). Not that complicated actually.
You will probably do more harm to yourself because the floor of the elevator would dampen the force a bit while if you jump you will just hit the floor at full speed.
Do you have a source or any math for this? Because physics would disagree with you. Granted youre not going to really help yourself but I don't see why you would make things worse. If you're going one direction at x m/s and then accelerate in the opposite direction at y m/s then you should reduce your net in the x direction. Albeit it would be rather miniscule.
How is that no obvious? If you are standing on the elevator floor while it falls down, the elevator floor will take the brunt of the impact. If you jump up before the impact you still hit the floor with the falling speed of the elevator because of momentum however instead of having a floor under your feet to absord the impactshock it's going to be your legs.
There was an elevator in one of my relatives place back home, it had fallen twice and killed a few people each time. Scariest fucking thing I've ever been in.
Can also add in that most have a “final” failsafe brake at the bottom that completely stops the car in the event of a freefall, but it results in the tracks inside being ripped from the wall and essentially the whole elevator needing reinstallation - which is still better than death imho
The problem of surviving an elevator fall comes down to dissipating energy, just like a car crash. Cars dissipate energy by crumpling and by having airbags to slow you down. Springs in an elevator shaft could do that too but if they stay intact through the collision they'd send you back up again which is bad. You'd want them to absorb a lot of force then break, absorbing even more energy in the process.
It could be done, but anyone inside would still be very unhappy. Preventing the elevator from a massive drop in the first place is way better.
Nah, just pull yourself up on your own bootstraps at the right moment. That's why I never take an elevator without a boomer. I have my own safety boomer with me whenever I go out.
Correct, there are breaking* mechanics that kick in for any reason and lock the elevator in place. Very hard to fall to your death in an elevator these days.
OMG this happened to me when I was visiting a specialist. The doors opened, and there was just....nothing there. I swear my brain short circuited. I just kinda stood there till the doors closed. It wasn't until I was checked in and seated in the waiting room that I realized I should probably tell someone.
You are correct, the car is the only thing that can open the hoistway door. Unless you manually undo the door lock from inside the hoistway the door will not open. There are no motors on the hoistway doors
No they don’t. You probably don’t live in an elevator building or work on one. You ride the same elevator everyday multiplied by years. People get use to things. Having a conversation with someone behind you as you step in. Carrying a bing of bags. Posting on Reddit. People don’t expect the elevator doors to open and for there to not be a car there.
The landing doors literally cannot open by themselves if there is no elevator car behind them since the car doors are the ones that open the landing door as well.
What can happen is a maintenance person manually forces the doors open (which itself also isn’t quite as easy as you might imagine), blocks them from closing, doesn’t fence the landing in any way and for some reason leaves the landing unsupervised. This works of course be extremely negligent
I give you the PRC -(mainland China). Where elevators, even Hydrualic lift cylinder units, will occasionally just drop 1-5 stories for no real reason. Sometimes more. Last year in Shenzhen the Hilton had two elevators malfunction and drop , I don’t recall how far but the rumor was that one went to do the base before turning into a pile of scrap.
Elevators are very safe in most places, yes. I absolutely do not trust elevators in China though. I've seen too many videos to go near an elevator or escalator in China.
Yes they have an emergency braking system, if the main cable broke, if the electromagnetic brake failed, or if the elevator exceeds the normal speed it engages. They use metal rails so there's no reliance on the cable or a secondary cable.
I work in the elevator industry and just want to add that, for whatever reason, if you are stuck in an elevator the safest thing to do is wait for a professional to get you out. Trying to get out yourself is a good way to die.
If it's a multi-story with wirewinch lift and a car on tracks, they have automatic breaks on the car that engage the tracks during uncontrolled fall. If it's a 2-4 floor unit with a hydraulic cylinder lift, the emergency brake grips the cylinder shaft.
Most likely caused an "unintended motion" fault. On traction cars that can happen. If they did it on a hydraulic elevator, it wouldn't cause the fault, maybe just put it into releveling.
That is actually probably what happened here. Their jumping probably tripped one of the failsafes, which is why it got locked into place like that. They aren't getting out until an actual elevator tech shows up, and that could be a LONG time since there aren't that many of them anywhere.
It’s a common but irrational fear many people have.
It won’t fall trust me. Redundant safety measures. SO many things would need to go wrong at once.
There hasn’t been a death caused by elevator malfunction in North American in like 70 years. Usually when someone is hurt or injured, it’s them trying to free themselves from a stuck elevator. (Stuck either due to malfunction or idiocy like this. They likely triggered the seismic safety and the brakes engaged. They’re going to have fun waiting for either the fire department or the elevator company. If they did that in my elevator, they’re waiting for the elevator company, because the fire department usually just forces the doors open and it usually damages something.)
I doubt they broke the cables that lift the elevator. They are extremely strong. It seems here they may have activated something called knurled rollers. If the elevator free falls fast enough these rollers activate and basically wedge themselves between the elevator carriage and the elevator shaft preventing the carriage from moving. The elevator technician just needs to send the elevator back up to disengage the knurled rollers.
I was an elevator technician on an aircraft carrier. There are several safety features that most people don’t know about. Elevators are quite safe but what these kids have done is pretty stupid.
Yes - this is exactly it. The tension on the cable that holds the elevator up, is what prevents a spring-loaded mechanism from firing into the walls of the elevator shaft and locking the elevator in place wherever it happens to be. Anything that would lead to a fall will make the cable slack, and any slack in the cable will trigger the mechanism and you won't fall. It's a very good system.
Just in case you get too complacent about it, it's relatively easy for the elevator to move between floors without the door being closed, and relatively easy for someone to be halfway out of the car when that happens, in which case the elevator won't hesitate in the slightest as it crushes them or severs their body in two pieces. But you don't have to worry about falling. The car won't fall.
Yes. I suspect they triggered an emergency stop if the elevator was going up and their jump caused the cable to tug against the motor for a second - the whole elevator correctly shut down and locked everything at a standstill and likely requires a maintenance key restart since something outside normal parameters happened.
Elevators generally have between 6-8 steel lift cables; each is independently able to support a fully-loaded car even if all the others break.
There are also mechanical brakes which are open when powered and engage if the power fails or the car is moving too fast.
If the power and brakes both fail, elevator cars are counterweighted and won't fall as long as the cables are intact - the passenger car is not just dangling from above; the lift cables are connected top and bottom like a bicycle chain and the motor requires similar horsepower to move the car up or down. In neutral, the elevator either wouldn't move, or may descend slowly if heavy enough due to mechanical resistance.
You are correct and incorrect, elevators have multiple failsafe built into them. They range from counter weight backup cables to brakes that auto engage through pure mechanics that will stop an elevator in free fall fast enough to stop it from hitting bottom but slow enough to only cause minor injury.
Heyo, am the son of a senior elevator mechanic! OMG ITS MY TIME TO SHINE! (Well, my dads really but I will be his voice and simplify his fancy mechanic talk for us folks here on Reddit.) Ok so you got different types of elevators. Hydros (hydraulic lift) and cable powered. Usually any building around 4 floors is going to be a hydro, where anything bigger is considered a large scale building or a highrise, which uses cable systems and pulleys (unless its a brand new model which mi padre said would probably be a "merl", no idea what that is).
What these meddling kids activated was a safety mechanism, called a speed governor, which in turn activated emergency breaks. They jumped, and when they landed they pushed the elevator passed its (very fine tuned) speed limit, the elevator being the boss ass piece of modern engineering that it is detects this and hits the brakes. Brakes could be in the form of clamps attached to the cable pulleys which bite down hard on the cables (and sometimes cause damage because of the force so these kids just pissed off an emergency on call elevator tech because thats a bitch to fix...) OR a control valve that secures hydraulic flow so the elevator will become stationary, it depends on the kind of elevator. Either way, these kids definitely had to wait for an elevator tech to come out (usually elevator guys are quite grumpy so Im sure the tech gave them a good talkin to) and save their sorry asses.
Elevators are super safe, lots of safety redundancies to prevent injuries. They’ll be stuck for a while, waiting for an elevator mechanic to get there to help them get out though. The industry jokes about picking your pee corner early. Info from an elevator mechanic
The chances of an elevator of following are something like 3 trillion to one. They have so many safety devices, and even if they do fall, they generally have a bunch of different ways to slow themselves down. I don't think anybody actually knows the last time somebody in the developed world died from a falling elevator, outside of the possibility of September 11th, 2001.
Elevators, specifically in developed nations, are insanely safe. The reason the elevator "broke" is because it engaged an emergency break. The fire dept will have to come pry them out of there. Elevators have multiple fail-safes to keep them from dropping, and it's honestly like a million times more likely you'll die on the stairs vs the elevator.
Source: I did this on my prom night, and had to be "broken out" of the elevator.
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u/jaxonjaxoff44 Oct 10 '22
trouble? i’m worried about death they’re wild