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Post by silverdragon on Jan 28, 2015 8:37:19 GMT
From QI, the best way to survive a lift falling is to lie on top of a fat person.
Now we all know that lifts have built in quadruple safety systems, but if one should fall......
"apparently", only one lift has ever had all of its cables severed in an accident, and that was the engine of a B54 bomber that went through the "empire state" sometime during WW2?....
The brakes worked, the lift didnt fall, everyone survived (from the lift)
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Post by craighudson on Jan 28, 2015 9:07:48 GMT
From QI, the best way to survive a lift falling is to lie on top of a fat person. Best compared to what? Jumping up at the right moment? |
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Post by silverdragon on Jan 28, 2015 9:13:12 GMT
Hasnt that one (jumping) already been busted?...
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Post by craighudson on Jan 28, 2015 13:28:14 GMT
Yes
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Post by GTCGreg on Jan 28, 2015 16:04:15 GMT
I thought that in the elevator fall episode, they said the best position would be to lay flat on the floor. Guess a fat person for a little extra padding couldn't hurt.
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Post by the light works on Jan 28, 2015 16:26:06 GMT
I thought that in the elevator fall episode, they said the best position would be to lay flat on the floor. Guess a fat person for a little extra padding couldn't hurt. of course, persuading the fat person to lie down so you can use them for an airbag might hurt you worse than just lying on the floor. |
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Post by mrfatso on Jan 28, 2015 19:47:20 GMT
From QI, the best way to survive a lift falling is to lie on top of a fat person. Now we all know that lifts have built in quadruple safety systems, but if one should fall...... "apparently", only one lift has ever had all of its cables severed in an accident, and that was the engine of a B54 bomber that went through the "empire state" sometime during WW2?.... The brakes worked, the lift didnt fall, everyone survived (from the lift) IIRC it was a B-17 Flying Fortress that hit the Empire State. No I remember wrong it was a B-25 Mitchell, the same type of bomber as used on the Doolittle raid. |
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Post by silverdragon on Jan 29, 2015 9:19:52 GMT
From QI, the best way to survive a lift falling is to lie on top of a fat person. Now we all know that lifts have built in quadruple safety systems, but if one should fall...... "apparently", only one lift has ever had all of its cables severed in an accident, and that was the engine of a B54 bomber that went through the "empire state" sometime during WW2?.... The brakes worked, the lift didnt fall, everyone survived (from the lift) IIRC it was a B-17 Flying Fortress that hit the Empire State. No I remember wrong it was a B-25 Mitchell, the same type of bomber as used on the Doolittle raid. Just what the hell is a b54 bomber anyway?...my typo..... Just where did that come from?... phat fingers. {Edit... yes one did exist, Boeing B54.} |
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Post by OziRiS on Jan 30, 2015 20:57:44 GMT
Just what the hell is a b54 bomber anyway?...my typo..... Just where did that come from?... phat fingers. {Edit... yes one did exist, Boeing B54.} B-52's even uglier older brother? To win that title, it'd have to be REALLY ugly, since the B-52's nickname is "BUFF", which stands for "Big Ugly Fat F***er"  |
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Post by silverdragon on Jan 31, 2015 8:04:22 GMT
This is a photo of one... I think...  |
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Post by c64 on Feb 6, 2015 12:41:34 GMT
The greatest danger isn't a lift falling down, the greatest danger is a lift "falling up"!
In an older lift, all safety mechanisms are designed to prevent that the lift can crash down. But a lift has a counterweight which is heavier than the empty cabin to save energy. When the counterweight and an average filled cabin have an equal weight, all the energy which is required is for friction only, no energy to lift the passengers required.
If there is a malfunction where the lift speeds up going up and fails to stop at the top, the cabin will crash into the top of the shaft very violently. Then people are propelled upwards towards the ceiling of the cabin and then crash back to the floor. Worse, the cabin may break. Then the safeties may become destroyed or the cabin crack open sending the passengers on a free fall without the cabin or with only parts of the cabin.
There are lots of lifts still in service without the modern "crashing up" safeguards.
I am not aware of any fatal "crashing up" incidents but there are many cases with (mostly leg) injuries known.
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Post by silverdragon on Feb 7, 2015 8:19:18 GMT
Now there is one you dont hear very often.
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Post by c64 on Feb 7, 2015 8:42:13 GMT
Now there is one you dont hear very often. Why would they advertise the scary not obvious truth? So if you want to be on the safe side, never ride an old lift alone, make sure there are at least half as many people inside as the maximum rated load. I have serviced an "ancient" hydraulic warehouse lift for many years and had a lot of good chats with lift service technicians and governmental approved safety inspectors. It's funny that they all know all of those bad "lift movies", especially the German "Abwärts" (Going down) and the Dutch "De Lift". |
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Post by ponytail61 on Feb 8, 2015 2:43:43 GMT
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Post by c64 on Feb 8, 2015 10:12:05 GMT
"Crashing up" prevention is only mandatory for new installations since a few years ago. There are many lifts still in service which were built in the 60s. You just can't tell since the cabin interior, the buttons and the logic of the lift was modernized. For example, 10 years ago, the Hercules Skyscraper in Cologne had to be equipped with new lifts since the electromechanical safety circuits (which all lifts, even state of the art ones have to have) were worn and the spare parts were not made any more since the early 80s. This part of the circuits may not be simply replaced by a new one. Designing and certifying a new safety circuit system was much more expensive than just replacing everything. The old lift did have a computer controlled floor logic, stainless steel buttons and a modern cabin interior. There was no way to tell that the lift was built in 1973! |
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Post by silverdragon on Feb 8, 2015 10:16:30 GMT
I was working in a factory with a HUGE cargo lift.
"Someone" asks what happens if the lift cable breaks.
They were worried.....
We had all the scare stories running for about a month, and they would never EVER ride that elevator....
'Cause they were scared shirt-less that the cables would snap.
Finally, some kind sole took them to the very obvious front of the lift and pointed out the HUGE hydraulic system that worked the thing... it was a giant scissor lift, no cables at all.
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Post by c64 on Feb 8, 2015 10:30:05 GMT
I've watched the video again.
Now this is a major malfunction. This simply can't happen with a lift allowed in Germany (and most EU countries). There are magnetic sensors (magnet + reed contact) on the doors (or at least mechanical switches). There are always two in series. If one of the doors, no matter if floor door or cabin door is a crack open, the entire circuit is broken. This circuit energizes relays (several in series) which feed the brake magnet and cut the power to the motor.
So if a door isn't properly locked, the brake is engaged and the motor has no power and the motor is short circuited.
If the brake fails, there is still the short circuited motor braking real hard when the cabin does move.
Also there is a tachymeter circuit on the motor which senses when the motor is turning. This at least breaks another safety circuit which prevents that the cabin door could open. There is also a switch on the brake monitoring if the brake is mechanically engaged and also breaks this circuit. But this was seen in the video, the doors reopened with the cabin moving!
So either the lift was tampered with or it had very poor safety standards in the first place.
It does happen that a caretaker simply bypasses a safety sensor/switch since (here in Germany), 90% of all stuck cabins are caused by defective safety sensors.
The usual method to "unstuck" a cabin is to go into the machine room of the lift, shut down the power of the logic and motor and then release the brake with a special wrench and then crank the cabin up or down to the end of the shaft. Then unlock the door safety with a key and push the door open.
In case of the hydraulic lifts I used to work with, you simply bleed the hydraulic pressure with a safety valve after disabling the pump motor and then collect the passengers in the basement floor. It was illegal to watch the floor indicator sensors and stop the cabin at the nearest floor. You had to lower the cabin all the way, then the cabin was about 3ft lower than the basement door but safely resting on the bottom bumpers.
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Post by c64 on Feb 8, 2015 10:51:44 GMT
I was working in a factory with a HUGE cargo lift. "Someone" asks what happens if the lift cable breaks. They were worried..... We had all the scare stories running for about a month, and they would never EVER ride that elevator.... 'Cause they were scared shirt-less that the cables would snap. Finally, some kind sole took them to the very obvious front of the lift and pointed out the HUGE hydraulic system that worked the thing... it was a giant scissor lift, no cables at all. I've never seen one of those. Ours use coaxial cylinders. I've worked in a building which used to have the fastest (and 4th tallest) hydraulic lift in the world. The pump system is truly gigantic. But there was a problem. How do dosage the amount of hydraulic fluid this fast. Usually, it worked quite well, but if many people use the cabin all the way and often, the oil turned very hot and expanded. Then the cabin moved too far up, stopped, needed a moment to think and then descended very slowly to the proper position. This took a lot of time making the people very uncomfortable - especially since it was a glass lift shaft with glass cabin! Now the speed is ordinary and there is a huge bypass loop for the pump. When you ride the lift, you can hear hundreds of horsepower running in a circle. The one in the warehouse was small but powerful. The sync of the coaxial cylinders was broken. When I reactivated the lift for the first time after we had got the building, I had banned passenger usage of the lift and disabled the cabin buttons. You had to load the elevator, then use the stairs and call the cabin to your floor. Being lazy, I installed a key switch for the cabin buttons. So whenever I worked there with the caretaker one of us could ride the elevator knowing that competent help is outside in case of a problem. And we did enjoy our rides with that half broken lift! There were "studentic workers" from the local University helping out very often. Almost all of them begged for the key. And every time I gave them the key, told them to have fun and watched. I really enjoyed this. When the capacity of the lift is half used, the sync of the cylinders turned real bad. The inner (small) cylinder then moved without the other (larger) cylinder. When it was fully extended between two floors, the other cylinder unstuck making the inner one retreat fast until the larger one hits the cabin floor rather hard. The result is that the cabin stops hard, descends for half a second and then the entire cabin crashes to a halt with a very intense hammer sound. The pump senses the pressure surge and stops. Then the lift is in emergency mode and reactivated the pump after a few seconds on "slow". Inside the cabin, you can't hear the pump any more and you don't feel any movement. Until the doors suddenly open at your floor about 2 minutes later. Myth confirmed, people's faces really can "turn green"!  |
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Post by silverdragon on Feb 8, 2015 10:57:52 GMT
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Post by c64 on Feb 8, 2015 11:09:44 GMT
Well, now there is no reason why they can't install a lift in Mount Everest... |
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