CHERNOBYL AZ-5 why it exploded

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  • karl karlsson
    karl karlsson 5 months ago +219

    Interesting fact: Sweden was the first country to notice that something had gone terribly wrong when the workers at a Swedish nuclear power-plant couldn't go through their own detectors without having them going off, they thought there was something wrong with their detectors until they tracked the radiation to Chernobyl, and expected the worse, so they picked up the phone and called them and received an answer that everything was OK and nothing bad had happened, so then Sweden called the US and explained the situation.

    • Dr.Chopper
      Dr.Chopper 9 days ago

      @Chris Anderson thank you very much

    • Chris Anderson
      Chris Anderson 18 days ago +1

      sweden always doing the best

    • Teracy Asu
      Teracy Asu 26 days ago

      And this was just less than 3 months after the PM was assassinated (Olof Palme) such a traumatic year for Sweden

  • Wholesome Sandwich
    Wholesome Sandwich Year ago +1556

    how ironic, chernobyl exploded because of a safety test and pressing the emergency shutdown button

    • EQOAnostalgia
      EQOAnostalgia Month ago

      @Styropian One of the best "Acthually" posts i read all day!

    • Corey Love
      Corey Love Month ago

      Oh The Irony!

    • GlowBeard
      GlowBeard Month ago +2

      @Styropian you should be pissed that you're so confidently wrong. When a reactor is shutdown, the nuclear fission chain reaction is stopped. No more energy is provided by the fissioning of the fuel. Heat is still produced though, from the decay of the elements created from the fission. This is about 7% of the pre-shutdown power level, and decays exponentially. It's about 1% 5 minutes after shutdown. This can't be stopped, it will always happen. But this is not a chain reaction, the neutron population is too low. There will be a subcritical equalibrium neutron level reached, which is a product of the previous power history and core age, but it will be orders of magnitude lower than the population needed for a critical chain reaction.

    • lokisg3
      lokisg3 3 months ago +2

      @Styropian
      I'm going try to make a simple analogy if possible to understand. You are drive a car at high speed, then you notice that your break fail to slow down the car. The car still moving at same speed of motion, you though it be good idea remove the car key from ignition hoping the car stop itself before hitting a car in front of you.

    • Michele Bellotti
      Michele Bellotti 3 months ago

      @crunchymixtotally false and ridiculous

  • Mod
    Mod Year ago +925

    amazingly explained
    amazingly presented
    amazingly narrated
    amazingly animated

    • Krak Head
      Krak Head Month ago

      Edit: New Zealeand*

    • Krak Head
      Krak Head Month ago

      Too bad it's hard to understand his thick Irish accent. He should do subtitles so we can understand from whom aren't from New Zealand

    • Weasle
      Weasle 2 months ago

      @Professional Bandit The reason modern reactors don't need graphite and can get away with only heavy water is because they use proper enriched uranium, whereas Chernobyl used primarily U238

    • Professional Bandit
      Professional Bandit 2 months ago

      @Weasle Chernobyl used graphite as a moderator. Modern US reactors use heavy water as a moderator. Chernobyl only used water as coolant

  • Xavier Sands
    Xavier Sands 11 months ago +537

    “Fireman said they warmed their hands over the graphite on the ground” that gave me chills

    • Aluminium
      Aluminium 5 days ago

      @Mystxx And yet hundreds of thousands of people take the show as fact.

    • NWA
      NWA Month ago

      BatChest

    • Darkpaw1
      Darkpaw1 Month ago

      This screams "cook me daddy" all over it.

    • Xavier Sands
      Xavier Sands 2 months ago

      @Blank Dude pick a fight with someone else I can’t be bothered

  • Mikael Andersson
    Mikael Andersson Year ago +1668

    This is probably the best and most interesting video I've even seen on the Chernobyl accident. The focus on the reactor physics among with the 3D models made all the difference compared to other videos mostly focusing on the consequences. I've shared the link to this video to a large Facebook group with focus on nuclear energy, hope this gives you many more views. Greetings from a NPP worker in Sweden :)

    • Jan Nowak
      Jan Nowak 2 months ago

      Most boring I`d say...

    • Robert Colajezzi
      Robert Colajezzi 3 months ago

      @Mike Bell thank you for responding, like immediately after the explosions and a couple days after the incident how did power grids cope with the lost energy? Any power outages?

    • Mike Bell
      Mike Bell  3 months ago

      @Robert Colajezzi Reactor 3 was switched off after 24 hours. Reactors 1 and 2 ran for another 2 weeks. The 3 were started up after radiation cleaning 6 months later and the last reactor ran till 2000.

    • Robert Colajezzi
      Robert Colajezzi 3 months ago

      @Mike Bell what happened to the power grids and everything connected to reactor number 4 after the explosion, like power loss and if so how long?

    • R228 NIRAJ LAISHRAM
      R228 NIRAJ LAISHRAM 4 months ago

      🤣🤣🤣

  • Erik Žiak
    Erik Žiak Year ago +420

    Let one thing be clear: The reactor did not behave in a way that was not known. It was known. But it was the policy of secrecy, suppressing information and general paranoia in the Soviet Union, that led to this disaster. The operators were highly skilled and professional. There was no "pressure" present (as depicted in the HBO series). They were cautious and confident in what they were doing. The problem is, they were not told the full story, the truth about the RBMK reactor and its design. Until the disaster at Chernobyl NPP, safety concerns were only from the viewpoint of how to protect workers from the radiation of the reactor. After Chernobyl, the safety shifted in how to protect the reactor from operator error. This was a very valuable lesson learned. The automatic reactor control and safety systems had to be manually disabled by operators at Chernobyl in order to do the test. They worked against the safety protocols and were aware of it. If they knew the full truth about how the reactor behaves in those conditions, they would have never ever do what they did. This was not the first time that this test went wrong. The Leningrad incident ten years before Chernobyl made this clear. Lucky for them, at Leningrad, they performed the test with a "fresh" reactor, which was not operated for extended periods of time. At Chernobyl, the fuel rods were burned up much more. The operational reactivity margin was way lower, which resulted in even more control rods to be withdrawn, making the reactor extremely unstable. The lesson learned from Chernobyl: Protect the reactor from human error. Today it is impossible to manually withdraw more control rods than is safe. Also design changes were made to the control rods, removing the graphite displacers with steel ones. The efficiency dropped a little and the fuel enrichment had to be raised a bit to compensate for that. I cannot stress this enough: The reactor did not fail. It was the human operators who failed. The design of the reactor was known to have certain issues and the designers knew of them. But the operators were not told the full truth. Even worse, after the incident at Leningrad NPP, where a similar test resulted in an almost identical result, the full truth about the reactor was not told to the operators. Human error and a paranoid mindset made the Chernobyl accident happen. The technology did not fail in any way. It was a human mistake and error. The lesson from Chernobyl is clear: If you do something, you must know at each point in time what you are doing and understand what, how and why works. If critical information is being kept from you, you inevitably make a mistake, sooner or later. All the natural laws are known and the reactor was designed properly. There was absolutely no miscalculation or misunderstanding in the laws of nature. There was just human error. The operators are not to blame. The whole culture is to blame, if it is poisoned by unnecessary secrecy and paranoia. Also, we need to protect delicate technology from humans the same way we protect humans (and the whole environment) from dangerous things like radiation, chemicals, etc.

    • Spider-Assassin7
      Spider-Assassin7 26 days ago +1

      Ok, Brotherhood of Steel.

    • The Network
      The Network 2 months ago

      @Peter Freeman Since when was that side of politics come from a discussion of how censorship can lead to human error one way or another?

    • Taras Wertelecki
      Taras Wertelecki 2 months ago

      @MinaOlenElla I have been in a nuclear reactor building, twice. A double roof would not be a containment building. The first explosion launched the reactor top right though the roof a kilometer into the air. That was how powerful the initial steam explosion was, the second hydrogen explosion was even greater. That threw graphite and fuel fragments all over the plant. People died of Acute Radiation Syndrome because a piece of fuel or graphite landing near them delivered a beyond lethal dose of radiation. A containment building is designed to contain everything even if the fuel melts down and burns through the bottom of the reactor vessel. They are also built to survive magnitude 8 earth quakes, even the impact of a jetliner at 500 mph. There were shock mounts, much like the ones I have installed on ships, but far more massive for the pipes, pumps, valves, electrical systems, hydraulics, anything vital to the safety of the reactor and the outside world. They can be sealed off from the outside world, and so can the control room unlike the one at Chernobyl. And at that, I am not sure three or four feet of specially made and reinforced concrete and a thick steel inner liner could have contained a RMBK reactor going prompt critical then launching the reactor top right off the vessel. The Corium, or nuclear lava created during meltdown that followed might still have burned through the bottom of the building even if it was built to western standards. The Soviet authorities have gambled nothing would go wrong and cut corners, and Ukrainians, Belorussians and Russians paid the price in death and suffering when they were proven to be wrong. Dead wrong. That was just the beginning as radiation covered much of Europe and Asia. But the chances were a strong containment building would probably have made all the difference had the Soviets learned from the West and put these reactors in them. If the exploded reactor remains remained contained, far fewer people would have died, if any.

    • Erik Žiak
      Erik Žiak 2 months ago

      @Dave Banach The did not know.

  • Neal B
    Neal B Year ago +511

    There were people at Chernobyl who made really bad decisions that, combined with design flaws in the reactor, lead to the disaster. But there were far more heroes present who limited the disaster to only the one reactor and prevented it from spreading to the other reactors. If the fires raging in the turbine hall had engulfed the other three reactors, much of Europe would be uninhabitable today.

    • tariq ayers
      tariq ayers Month ago

      @cytrynowy_melon “tell me your stupid without telling me your stupid” 🤣😂. If all 4 reactors had exploded at least half of Europe would not only be uninhabitable but dead.

    • Ya boi [Cotten Candy gacha]
      Ya boi [Cotten Candy gacha] 4 months ago

      @cptnoremac you lost the arguement. You are just too stubborn to admit you are wrong. But it doesn't mean you then go and attack other commenters.

    • Taras Wertelecki
      Taras Wertelecki 5 months ago

      @Bill Smith Unless that is, one is at the site when it happened. Hard to believe firefighters who came to put out the fires had no idea they were walking into a lethally radioactive area that was also on fire.

    • Bill Smith
      Bill Smith 5 months ago +2

      I was a nuclear reactor operator for the United States Navy. All of this Doom and Gloom and worldwide extinction event talk is just a bunch of bunk. Could it have been much worse, yes. Couldn't have destroyed Europe or killed everybody in Europe or anything crazy like that, no. Nuclear fallout reduces exponentially the further you get from the source. That's why you can go there today and get within a few hundred yards of the reactor and be just fine. Only about 4,000 people died from the Chernobyl event, and more people died than that learning how to transport gasoline safely at the turn of the last century. The fear of radiation and nuclear meltdown is way overblown.

  • Richard Hudgins
    Richard Hudgins 4 months ago +41

    What is sad is that the engineers who built and operated the reactor were not stupid. They were, as most nuclear engineers generally are, brilliant people. The problem is that in a totalitarian regime such as the Soviet Union, bureaucracy and politics often overrule sound engineering. The saying, "When science meets politics, politics always wins", might apply here. A lot of group-think, a system that discouraged anyone speaking up, and pressure to just make things work resulted in a disaster that cost many brave men and women their lives. Thankfully the lessons learned have led to improvements around the world.

  • Lady Ivy Vine XIII
    Lady Ivy Vine XIII 10 months ago +25

    Such a tragic loss of life. We have to commend the operators who sacrificed their lives to keep the other 4 reactors from suffering the same fate. Chernobyl was a huge disaster, but it could have been so much worse.

    • Manny93
      Manny93 9 months ago

      Haha yea. There are some videos on YT showing people visiting the locations of the new reactor buildings

    • Lady Ivy Vine XIII
      Lady Ivy Vine XIII 9 months ago

      @Manny93 Ok, that's why I have heard of more than 4. I can understand why the other two were nixed.

    • Manny93
      Manny93 9 months ago

      Chernobyl only had 4 reactors at the time of the accident. But they were building unit 5 and 6 at the time who was never completed. The last reactor shut down early 2000

  • Grim 13
    Grim 13 11 months ago +33

    I come back to Chernobyl documentaries and such every couple of years, kind of a tradition if you will, and I must say what You've done here is amazing! You've managed to tell the story and effectively explain what happened in 13 minutes, and still do it better than most 30-60 minute lectures and make it more clear visually than 45-90 minute documentaries.
    Bravo, good Sir!

  • Erik Hendrickson
    Erik Hendrickson 5 months ago +8

    The amount of energy required to send the two MILLION pound reactor lid 100' in the air is absolutely terrifying!

  • Richard Palframan
    Richard Palframan 9 months ago +45

    This is one of the few accurate videos that explain the events of that night in simplistic terms without clouding the facts with 'untruths'. Good job Mike,

  • patentlyrubbish
    patentlyrubbish Year ago +25

    I think you're right to remind that this was designed in an earlier time, without much of the detailed knowledge and modelling that we now have, and that it is easy to criticise individuals who did not have the benefit of our hindsight. However, that said, it's pretty reasonable to criticise a system that allowed the reactor to start work before its safety testing was complete, placed very clear pressure on its engineers to complete the test regardless of whether the moment was suitable or not, and decided not to tell them about known flaws in its emergency shutdown systems. Just as this was a steam and gas explosion not a nuclear one, the root problem was a managerial failure not a technical one.

    • Taras Wertelecki
      Taras Wertelecki 5 months ago +2

      @Amy Weinholtz The U.S. also has done its share in that regard, and then some. And we also had nuclear accidents that have killed people horribly by radiation poisoning and acute radiation sickness.

    • Amy Weinholtz
      Amy Weinholtz 11 months ago +2

      No. Partly true but russia has often produced cheap, quick and nasty technology that kills people. In fact this was not the first russian nuclear accident.

    • vidgamarr
      vidgamarr 11 months ago +5

      Human Incompetence. The source of 99.8% of the world’s problems.

  • venator5
    venator5 Year ago +2868

    When the button supposed to kill the reactor takes the word literally.

  • Алексей Волков

    Спасибо за адекватную оценку произошедшего, грамотное объяснение физики реактора, а так же за отличную анимацию!

  • Jake Wallwork
    Jake Wallwork 9 months ago +10

    I just have to say, incredible work! The animations, the attention to detail, the 3d rendering, the information served. By far the most informative and polished animated info-videos I've seen! Fantastic work 👍🏻

  • wss wetghg
    wss wetghg Year ago +10

    Extremelly well done animation! A mistake not already mentioned is that there were no channel ruptures at Ignalina. Ignalina is where tip effect was discovered, not Leningrad.
    Also, you should have mentioned the spatial problem: core too big, essentially ~40 reactors under one cover. It only took a small fraction of the core to go supercritical for the disaster to happen.

    • Taras Wertelecki
      Taras Wertelecki 3 months ago

      Correct. The failure of several fuel channels was the cause of the first explosion that flung away the 1,000 ton reactor top. Steam pressure built up in a "hotspot" at the base of the core so rapidly in those fuel channels they ruptured and the steam escaped beneath the reactor lid. It soon built up rapidly enough to fling away the reactor lid and all the control rods right through the roof a kilometer into the air. When that happened, all the other fuel channels which were also at extreme pressure were suddenly open to the atmosphere, and the water in them flashed to steam too. That was followed by the second explosion which occurred when hydrogen, red hot graphite and oxygen from the air came into contact with one another.

  • Cameron Boberick
    Cameron Boberick Year ago +13

    This was the video I have been looking for, for years now! A well explained, detailed, animated account of what had happened. You put the perfect amount of technical information on how the RBMK reactors work, and how they’re flawed. Great job.

    • Mike Bell
      Mike Bell  Year ago +2

      I set out to achieve exactly what you describe. I'm glad you think so and the your comment is much appreciated.

  • drst00
    drst00 2 months ago +4

    Thank you for this video. After the HBO series came out I was intrigued and researched and read various independent sources. I reached the same conclusion which you emphasize in this video, and which was unfortunately misreported in the series
    It is not that the operators brought the the reactor to the point of explosion and the AZ-5 was "too late" to help. It's the fact that due to the design flaws, the AZ-5 itself is what blew it up.
    Yes, the conditions that led to this situation were due to a sequence of wrong decisions by the operators, however, as you said - they did not know about these flaws. The best phrase I've seen in this context goes something like: "The question of fault of the operating personnel should be addressed in a context of one's accountability while sitting on a keg of gunpowder, completely unaware".
    The designers of the reactor were fully aware of the flaws, thanks to those earlier smaller accidents you mentioned. But only after the big disaster they got around to fixing them, quickly and efficiently, across all remaining RBMK reactors, quietly and without ever admitting any responsibility. Shameful.

  • K Jamison
    K Jamison Year ago +231

    Western Nuclear advice: “If in doubt, ask!”
    Soviet Nuclear advice: “If in doubt, you are delirious. Take this man to the infirmary!”

    • lokisg3
      lokisg3 3 months ago

      @Brent Farvors
      Bro, they actually have the sea walls that time. They just never seen the tsunami that high before and placing the power generator in the basement of the plant is a bad idea. Another thing, melted corium will cool down in time, we call it an elephant foot and no, it still contain inside the reactor concrete base. How you know it still there? Well most electronic device died by high level of radiation each time they try to look into the core, is when they able to see what inside then we are in big trouble.

    • lokisg3
      lokisg3 3 months ago

      @Red Sun
      I think there is misconception thinking building a reactor next to the sea is bad but it actually a good thing. This is only way to avoid meltdown is pumping water and if need to, the sea provided all the water you need.
      The main issue is the water pumping station and emergency generator to pump water, they were build under the basement of the plant. Years before the accident, the atomic inspector did warn the plant managers about the risk putting generator under sea level even if nearly impossible to flood because there no record in history for tsunami to be that high happen before. So they just install a door to block it which later on we know it will not stop the tsunami from entering.
      What they never expected is the tsunami is far above the high of the sea wall, no history of this high have ever come this before. Any East coast of Japan with sea wall deem useless thus catching off guard to most Japanese living near the coast. Thus, the water start to spill over the sea wall and down into the basement.
      That the reason why the reactor when critical, it was generating a lot of heat without water and all the water from the sea still can't pump because the power generator is now half flooded.
      I can go on but maybe you should watch most video in TheXvid, they far expert than me.
      Another misconception is radiation, is atom on the move and water is very good at stopping it. Yes, I agree with you is not glamour's to dumb water just like that but they mostly treated water, barely even register radiation. Still, people forget that we dumbing thousand ton of plastic in the ocean and overfishing.
      The weird part is death toll from fukushima plant to people, so far I know is 1. Yes, confirm 1 death that involved to the accident at the plant, report on radiation sickness is mix but I last heard is around 8. For Tsunami in 2011, 18,000 people were kill and missing during that day.
      So I not sure why people remember fukushima but forget there a Tsunami in 2011.

    • PlayMates
      PlayMates 5 months ago

      @Watcher3223 true

    • Watcher3223
      Watcher3223 8 months ago +2

      @Dawn Donivan Well, to fair, Fukushima Daiichi survived the quakes.
      It was the tsunami that did it in.

    • Dawn Donivan
      Dawn Donivan 9 months ago

      @Red Sun I'm actually very surprised that the Japanese did this knowing how often they have earthquakes.

  • Russki Blusski
    Russki Blusski 10 months ago +17

    As someone who has done a lot of reading and digging on what was going on in that reactor that night. This so by far the best video I have seen on the subject.

  • berelinde
    berelinde 11 months ago +5

    Thank you for explaining this so clearly. No lie, I have been trying to get my head around it for 35 years, ever since the disaster. I understood that whole xenon poisoning thing and how a sudden spike in reactivity in the absence of control rods would lead to destruction, but I didn't understand why the graphite tipped control rods or the AZ-5 activation led to the sudden power spike. I'm going to watch this again so it really sinks in, but I think I finally get it now. (For the record, I'm not unintelligent. I'm a chemist, and I did well at university. It's just that nuclear physics is not the easiest subject, even when the listener basically knows how atoms work. it's that whole moderator/control/fast neutron/void coefficient thing that gets confusing. In short, all of it.)

    • Вован
      Вован 10 months ago +3

      Graphite is a moderator. When a graphite displacer moves down the channel, it displaces water from below. As it not as long as the core part of a channel itself, there's particular amount of water in the lower part of the core inside the control rod channels. Water isn't a good moderator, it consumes neutrons, slowing down the chain reaction. Graphite is the opposite. It doesn't consume neutrons (or not as much), and it slow fast neutrons down to the thermal velocity at which they could be consumed by an atom and cause it to split. So when the bad moderator is replaced with good moderator, you have a power spike in that region. And if you have the water inside the reactor close to the boiling point, it can boil because of that spike. Steam has less density and consumes less neutrons than water, so amount of steam inside the core affect reactivity. So on the power spike caused by water being replaced with graphite you have yet another spike, when water is replaced with steam.

  • Mark Young
    Mark Young 9 months ago +4

    Your modelling of the systems, animation is without doubt the best I’ve ever seen on this.
    More than all this all, thank you for showing care and understanding of this catastrophic event.
    I’ve have subscribed to your channel and look forward to more uploads.
    Well done!

    • Mike Bell
      Mike Bell  9 months ago +1

      Feedback is appreciated and thanks for the subscribe. Now i need to find more time for animating. 😁

  • Jan Andrea
    Jan Andrea 11 months ago +2

    This is spectacular animation, and really helped me visualize what happened. Thank you for all your hard work!

  • Frankie Rzucek Jr
    Frankie Rzucek Jr 29 days ago

    This was really fascinating, thank you for all the work you put into this. I always wondered what had really happened

  • 𝕲𝖔𝖉 𝖔𝖋 𝕿𝖍𝖚𝖓𝖉𝖊𝖗

    Great video. Always been fascinated with Chernobyl and 90% of the videos I've watched that don't address the lower portion of the reactor being the fuse, this video explains it the best. This was the mother of all pressure cooker explosions and not a nuclear bomb. It would have been exponentially worse (though impossible) for to it have detonated as a bomb. The other reactors would have blown as well. All the pressure went up, thankfully. Though the worst nuclear disaster in human history (so far) it could have been so much worse.
    Cheers, I enjoyed that.

    • Taras Wertelecki
      Taras Wertelecki 3 months ago

      If it was close to Kiev, it would have been far worse, with many dying of Acute Radiation Syndrome. Look how slow the authorities were to evacute the people living near the plant. How would three million people possibly be evacuated in time even here in the West, let alone Ukraine?

  • Rocket
    Rocket Year ago +4182

    When you complete the five year plan energy production in less than 15 seconds. Smart move

    • Bimba007
      Bimba007 11 days ago

      Che strana coincidenza l' arresto per colmare un deficit energetico a Kiev .... è ancora più strano il test eseguito dalla equipe non esperta..... toh quante coincidenze

    • duMaurier
      duMaurier Month ago

      hi China.

    • SleeplessThroughSleepingWorld
      SleeplessThroughSleepingWorld Month ago

      THE FUTURE CANCER IN YOU THINK THE SAME

    • Jet Fighter Pilot
      Jet Fighter Pilot Month ago

      Feels like starting and finishing a school project at 7am

  • jime6688
    jime6688 9 months ago +2

    Very informative, although as a layperson, a lot of this is still above me. I just Marvel that engineers and physicists are able to design and build such things. Failures happen, but when something like this works, it works extremely well and I just can’t get over the genius of nuclear power.

  • Drew B
    Drew B Month ago +1

    This is so well done. Thank you. I was 15 years old when this accident occurred and of course I did really understand the seriousness of what had occurred. I mean, I understood it was a terrible tragedy but I didn't understand what had occurred. Decades later, all I feel is profound respect for all of the men and women who sacrificed life and health in an attempt to mitigate further damage and who, ran towards the burning building.

  • Cappen Boidseye
    Cappen Boidseye Year ago +5

    Excellent explanation, without getting to deep into reactor physics, you did a grand job there!

  • MrJokkoma
    MrJokkoma Year ago +27

    You should take on more disasters that has happened in the past, best animation so far and I appreciate that you talk calm and collected.

  • Chris Anderson
    Chris Anderson 18 days ago

    This was very well done, and all the information I could ever want in a very well made animation. This is S+ Tier.

  • Somebody once
    Somebody once Year ago +34

    That piece that got blown up to the air and fell down back to the reactor wasn't a lid, it was the Elena - a bio-shield. Incredible animation and explanation tho, exceptional work my man!

    • CherryIsTrash
      CherryIsTrash 6 months ago

      @Somebody once Who cares

    • Melissa Wickersham
      Melissa Wickersham Year ago +1

      Technically, it’s both a lid and a shield.

    • Somebody once
      Somebody once Year ago

      @Deathjr112 and in fact, the RBMK reactors really have lids, it's the surface the workers can step on.

    • Somebody once
      Somebody once Year ago

      @Deathjr112 ohok, but anyways, calling it a reactor lid is wrong, because it's a Bio-Shield. It's like everyone calls an airplane engine a ''turbine'', but it's called ''engine'', turbine is just a piece that is assembled inside the engine, got it?

  • Major Calibere
    Major Calibere 5 months ago +5

    RBMK was a *criminally reckless* design, even for the 1960s, and no Physicist will say otherwise. No Western LWR is anywhere near this dangerous.

  • Skye Roy
    Skye Roy 5 months ago

    Thank you for showing a cutaway of the tank and how the control rods moved in and out. I was always confused as to what exactly it looked like and didn't understand the space that allowed for that to happen. Now I'm curious as to what's inside and at the bottom that moves the control rods themselves. Is it some kind of rollers?

  • Ian Anderson
    Ian Anderson Year ago +665

    The transitions from the the animation to the real reactor were amazing.

  • puncheex2
    puncheex2 Year ago +4

    Another excellently done animation, Mike. I have been told by operators that there are procedures for bringing a poisoned reactor back to working levels, but those are water reactors; increasing the power in the reactor does burn off the poison, and the operators have to be following the reactivity very closely to be inserting control rods as the poison is burned off, but it can be and apparently is done. That they should be trying it on third shift with the lack of attention and with safety equipment shut off in preparation for the test seems criminal. I was gratified to hear that you believe that the reactor did not suffer a criticality accident, that it was steam and hydrogen; there seems to be a lot of people who want some sort of criticality to be the explanation.

    • Taras Wertelecki
      Taras Wertelecki 5 months ago

      @Mike Bell Even if it was, it was a "fizzle," fortunately.

    • Mike Bell
      Mike Bell  Year ago +1

      Many comments in my previous video repeatedly insisting it was nuclear. In fact they know it was one, apparently there are mathematical calculations ... LOL

  • HyenaDog
    HyenaDog 7 months ago

    Love this video. Explains everything in a concise manner and I really love the 3D cutaway animations so we can get a sneak peek inside the reactor.

  • PlaneBox
    PlaneBox 9 months ago +2

    The Chernobyl accident in 1986 was the result of a flawed reactor design that was operated with inadequately trained personnel. The resulting steam explosion and fires released at least 5% of the radioactive reactor core into the environment, with the deposition of radioactive materials in many parts of Europe.

  • HiVizRiz
    HiVizRiz 5 months ago +1

    As a mechanical engineer working in the nuclear sector, I have to commend the quality of the building and mechanical equipment models in this video. Very well done sir!

  • SerMattzio
    SerMattzio Year ago

    Great video, well animated, you deserve more subs :)
    I'd actually love to see more videos like this describing disasters or scientific principles.

  • KanamixOtoah
    KanamixOtoah Year ago +5

    I've watched several videos about this, yours is the first that actually gives a decent visual and explanation for what exactly happened! Thank you!

  • artisanrox
    artisanrox Month ago +1

    I also want to comment how helpful the utterly seamless transitions from animation to the real thing were. Made everything so clear. Thanks for this educational experience of this horrific event.

  • Dr. James Olack
    Dr. James Olack 9 months ago +1

    Most thorough explanation of the Chernobyl incident I’ve ever come across. You guys deserve some kind of award for this exceptional, play by play description of one of the most serious nuclear disasters in history. Very well done Matt and Mike Bell. Bravo!!!
    Edit: Instant new sub here from Columbia, Missouri, USA 🇺🇸 And a big 👍 for everyone who played a part in this remarkable video!

    • Mike Bell
      Mike Bell  9 months ago

      Awesome. Thanks for the subscribe 😊

  • Nick be Gaming
    Nick be Gaming 5 months ago +2

    Thanks so much! You clearly know what you are talking about! I love learning about history so thanks so much! Good work!

  • Rafael 7
    Rafael 7 11 months ago +5

    Parabéns exelente documentário, obrigado por colocar opção de legenda em português e 🇧🇷🇧🇷🇧🇷🇧🇷👍🏾

  • jose carlos
    jose carlos 9 months ago +2

    Excellent video and explanation; however it leaves out the fact part of the test required the auxiliary water pumps/cooling system to be turned off...no water, what little was left in the fuel channels superheated and the rest is history.

  • Wilhelm Bittrich
    Wilhelm Bittrich Month ago

    This was a GREAT video! I've read a lot about the Chenobyl disaster, but the way this video explained it well with a combination of visuals that really makes you understand it a lot better. You've earned another subscriber.

  • SEGA-NES MAXIMUS
    SEGA-NES MAXIMUS Year ago +154

    This was amazing to watch!
    I’ve read up, and understand every part of why the reactor went into a meltdown phase, but your video was able to explain every detail, and every part of it all... in under 13 minutes!!
    That’s an amazing feat! Great job on this!

    • Alhambra Project
      Alhambra Project 5 months ago

      I have heard that the heat was so intense at the bottom that things melted and control rods could not move down

    • Cyberfunk
      Cyberfunk 11 months ago +1

      @Chenga Animates "so when it was lowered, it displaced the water at the bottom of the reactor, to the point where there was almost nothing controlling neutrons at the bottom of the reactor, which caused a localized power surge"
      And this would have been compensated for by the water(or boron in the control rods) replacing the position higher up where the graphite had been before, so the net reactivity would have been less unless for some reason the reactor was functioning very unevenly and there was significantly more reactivity lower down, which would be strange as the temperature is higher the higher you go so it should be the opposite: more reaction higher up or at the center.
      "This was explained in-video, by the way."
      The explanation doesn't add up, as I made clear, by the way.

    • Chenga Animates
      Chenga Animates 11 months ago +2

      @Cyberfunk The graphite didn't reach all the way to the bottom of the reactor, so when it was lowered, it displaced the water at the bottom of the reactor, to the point where there was almost nothing controlling neutrons at the bottom of the reactor, which caused a localized power surge. This was explained in-video, by the way.

    • Cyberfunk
      Cyberfunk Year ago +2

      Well if you understand it, can you explain why lowering the graphite that is already in the reactor would increase reactivity? Water at the bottom is replaced by boron on top - net result surely is less reactivity, not more, and afaik the reactor is hottest at the top, not the bottom? The only thing that makes sense to me is this explanation if for some reason the reactor was really uneven, and even though net reactivity decreased, it increased locally so much in the bottom to cause the explosion. The other option would be that the rods were actually pulled out so far that the graphite was out of the reactor until the button was pressed.

  • Brandon Nelson
    Brandon Nelson Year ago +1

    What an excellent way to explain what took place. Thanks for the hard work!

  • Rico 1071
    Rico 1071 8 months ago

    Outstanding work and you’ve got a great presentation style. This is proper documentary standard and was a balanced and fair assessment

  • 03fromIP
    03fromIP 10 months ago

    Honestly one of the best videos on this subject providing technical details clearly without a lot of unnecessary dialogue.

  • Name
    Name Year ago +3

    amazing explanation and narration of the unfortunate event. nuclear reactors are unfortunately on a rapid decline, i'm afraid fission reactors are being phased out with more going into decommissioning and very few are being built.

    • Neb6
      Neb6 Year ago

      More like Fortunately they're going into decline, considering that they're pretty much impossible to remediate after critical failure and the waste products are a hassle with no truly safe long-term storage solution.

  • Jan Skácel
    Jan Skácel Year ago +5

    2:27 Correction. Neutrons released from fission have mean velocity in region of 20 Mm/s. Very far from "nearly speed of light".

  • πRMD
    πRMD Year ago +1

    This video really gave me clarity about the dynamics of the problems that occurred to the reactor, the best of all the other videos I've been watching lately. Indeed I've just decided to deepen my knowledge of this disaster from an engineering point of view and this video just came out! What a fortunate coincidence. Anyway I hope it will make also people more aware of the conditions that brought this explosive result and restore a bit of faith in nuclear power plants as a perfect substitute to fossil fuels engery production. It inspires me every time such technological advancements and my country, Italy, would only benefit.

  • LiamJStillPlayz
    LiamJStillPlayz 4 months ago +1

    This video honestly helped me with a history project because it's so detailed and awesome!

  • Potato
    Potato Year ago +1

    The animation is really good. The explanation is pure, no unnecessary talking. Great job!

  • Nick Porter
    Nick Porter 6 months ago +1

    Just watched the (excellent) TV series again and watched this video by way of explanation of some of the science behind the disaster. Many thanks Mike as it was most informative.

  • Spoutnik
    Spoutnik 2 months ago

    Merci pour les sous titres en Français ! Sa fait plaisir d'avoir un véritable documentaire de qualité.

  • Dizzydude
    Dizzydude 7 months ago

    The accuracy on this video is stunning, also the reason the AZ-5 rods took so long to go in was because the ministry medium machine building or something like that had the AZ-5 rods hooked up to the same motors for the control rods? Which meant that they wouldn't immediately fall in, but slowly descend.

  • Michael M.
    Michael M. 8 months ago

    This is a beautiful, accurate, informative and respectful video. Thank you so much!

  • BaHeK83
    BaHeK83 11 months ago +1

    Excellent explanation! So short and so understandable. Without useless emotions and, finally, more positive then negative ending

  • Melikşah Arslan
    Melikşah Arslan 9 months ago +1

    Wonderful animations! Please keep up with this great work!

  • vikas singh
    vikas singh Year ago +1

    The best video (both in terms of presentation and educational value) I've ever seen on Chernobyl. Thank you so much❤️

  • Igor Zherebiatev
    Igor Zherebiatev Year ago +1

    Only one thing I have to add to this excellent video. At the time of disaster instructions were different and allowed operations with only 7 to 15 equal rods. 26 appeared only in 1987. Dyatlov in his memoirs mentioned that.

  • Joel
    Joel 9 months ago +1

    This is the clearest Chernobyl explanation I have ever had. Thanks so much Mike

  • MrKnoxguy101
    MrKnoxguy101 2 months ago

    Hoping to achieve a better understanding, I’ve always wanted someone to make a video giving a visual reference as to what took place that night within the RBMK reactor when things went wrong, and you did this masterfully. Thank you.

  • Dr.Chopper
    Dr.Chopper 9 days ago +1

    Finally, someone who explains it so even someone with no knowledge of nuclear power could understand

  • IzzoSkizzy
    IzzoSkizzy Year ago

    This is a fantastic visualization of the plant and disaster. Thank you!

  • MrChyort
    MrChyort Year ago +47

    Good video overall, but here are some corrections:
    4:20 - The graphite sections were cut short because there wasn't enough space below the core, rather than to equalize fuel burn.
    4:45 - The previous test had been performed just after a reactor startup, but on April 26 there was a shutdown planned.
    5:00 - Running the reactor at half power did not poison it. On the contrary it gave time for the xenon to burn off. If not for the delay, the poisoning would have been worse. Xenon is not a contributing factor to the accident any more than gravity contributes to a skydiving accident.
    6:00 - The rules at the time DID allow for restoring power regardless of Xenon, so long as certain conditions were met. It is ambiguous whether any rules were broken, but at the time the operators would not have seen any clear reason not to continue.
    6:15 - The control rods were in a normal and allowed position after restoring power for the test. But later changes to coolant flow and temperature meant that more rods had to be removed. The car analogy is silly because the RBMK was designed to be operated like this (fewer rods inserted = greater fuel efficiency).
    6:45 - The personnel had agreed to push AZ-5 at the START of the test, but apparently there was some confusion and this action was delayed for 36 seconds.
    7:15 - An entire group of automatic control rods was fully inserted, and another set was in motion as well. There is nothing 'frightening' about no rods being fully inserted; this is just how the RBMK was supposed to be.
    7:25 - In practice the limit was 15 rods, not 26. RBMKs had to regularly operate with less than 26 rods, and operators were unable to track short-term fluctuations in this value because at low power there was no instrument capable of tracking it.
    7:38 - AZ-5 did NOT insert any rods from below. If it had, the reactor would have been saved. This safety improvement was scheduled to be implemented following the scheduled shutdown.

    • Richard Trent II
      Richard Trent II Year ago

      @Paul Mobley I'm not sure why I got a notification dragging me back into this argument a week out. This section is so tiring. I don't mind answering questions, just this argument is the same thing over and over for 160 comments.
      I did take the time to reread almost all of them.
      Anyways just wanted to let you know, in a lot of your comments involving 'OBT', except for one comment, where you were typing your knowledge, you keep writing "OBT" and referring to it as "organically bonded Tritium."
      The correct term is "organically bound Tritium", of which used by you only 1 week ago, where you capitalized the entire definition of OBT, and listed the correct terminology.
      OH, and your long written explanation of the explosion was closer to a correct way of things happening. The reason why I went over the difference of explosions to begin with is that for your first few comments you kept saying 'nuclear explosion'. I was trying to correct your terminology of calling an explosion at a nuclear power plant a nuclear explosion, there can not be a nuclear explosion at a nuclear power plant.
      Lastly when oxygen and hydrogen meet, they do not spontaneously explode. There must be an outside element (heat, like in the water balloon experiment) to the chemical reaction to cause combustion. You have several times mentioned this reaction, stating that 'when the hydrogen from the pressure vessel met with the oxygen in the air it exploded'. In a way that is true but you really should include the element that actually caused the explosion, the heat. In the balloon experiment most use a lighter, others have used a spark. Also that a pure hydrogen explosion isn't possible either, hydrogen with out the oxygen can not burn.
      Here is the current understanding of OBT in the environment, though I think this one is from 2013.
      pubmed.ncbi.nlm.nih.gov/23962797/

    • Richard Trent II
      Richard Trent II Year ago

      If anyone here has any questions about nuclear power, I am more than willing to try and answer them for you. Feel free to leave a comment (doesn't give me notifications on this thread for some reason), if they're is a way you could message me too.
      For some long reading about chernobyl, you should look for the official reports, there is one, i believe 189 pages long, and an updated one with newer information 148 pages long. And there is a good website that goes over it all in a web page style, kind of like older online learning style, all 3 are official and I'll link here at the bottom.
      Finally, if you want to learn more about nuclear power here will be some search terms, the more basic the terms, the more likely to bring up anti-nuclear activists sites, instead of true information. For example 'nuclear power' is very and lots of times shows up a lot of activist things, however it turns up a lot of good information too.
      Search terms like 'UN and nuclear power', 'WHO nuclear power' put in all kinds of stuff in front of nuclear power. Can use like 'United States thoughts on nuclear power'
      'how is nuclear power safe?', 'why is nuclear power one of the safest and cleanest forms of energy production' , 'what is the lifetime emissions of a nuclear power plant' (mind you that this number gets way smaller and way better as the plants continue to keep aging more and more time to their life time, extensions), 'banana radiation comparison ', 'how is China going to get 0 emissions by 2030', 'what is an smr?' 'why are SMRs great?', 'can SMRs help rural communities, or third world countries? "
      'why did France build up such a large nuclear power generation' 'how much will the shutdown of the nuke plants in France hurt the country and its economy' 'how much does France make off of selling nuclear energy?'
      There are so many more too.
      Don't forget to search 'how has false fears hurt the nuclear industry'
      Search about why anti-nuclear lie or stretch the truth to fear people.
      The possibilities are endless. Have fun!
      www-pub.iaea.org/MTCD/publications/PDF/Pub913e_web.pdf
      www.iaea.org/newscenter/focus/chernobyl

    • jonny tightlips
      jonny tightlips Year ago +2

      @MrChyort I will definitely pick your brains....
      Yes with everything going on at the moment it sadly almost got over looked. I was meant to to be there at the end of last year on a 4 days visit throughout the exclusion zone and of course the power station, but lock down sadly put an end to that. Waiting for overseas travel to open up again to re-book the trip.

    • MrChyort
      MrChyort Year ago +1

      @jonny tightlips Ask away if you want. There are so many amazing sources which still haven't been translated, although all the interest from HBO is changing that to some extent. Too bad the 35th anniversary snuck up me, it would have been a good time to write some sort of article about the topic.

    • jonny tightlips
      jonny tightlips Year ago +2

      @MrChyort absolutely agree, its nice to talk to someone with such a vast knowledge base of the subject.
      I have read everything I can find on chernobyl and still have a million questions.

  • Bernardo Carvalho
    Bernardo Carvalho Year ago +2

    This must have taken ages to create, yet you chose quality, despite the difficulties, thank you, very well done!

  • K Quinn
    K Quinn 11 months ago

    Very well done. One important aspect: the test the operators ran that night was supposed to have been done years earlier, but had been put off. In reality, the test did not need to be run at all as they knew from the other units that the flywheel effect was sufficient to keep the coolant circulating until the diesel generators kicked in.

  • Terry Clark
    Terry Clark Year ago

    Thanks for sharing this great animation. One question though, if I understand it right the xenon forms within the fuel pellets and is contained within the fuel assembly. So I don't think it speeds throughout the core like in the animation.

    • Mike Bell
      Mike Bell  Year ago

      That is correct. That is why there is a note which makes clear it is locked in the tubes. The animation just looks cool and gets the message across.

  • Erik Scanlan
    Erik Scanlan 8 months ago +2

    I heard that it blew a multi ton plate about 1 kilometer into the air. Just before that there were 900lb. Bars rattling around. At 1:23:40 they made some change and then 4 seconds later at 1:23:44, there is a pressure explosion. I can link anyone here to some rare footage provided through a professor who teaches about Nuclear Fission and the such.

  • John Williams
    John Williams Year ago +200

    Just breath taking, you answered my little questions like why the control room is scavenged up till today

    • Data Point
      Data Point 5 months ago

      I mean, I have several gauges and old switch gear from various dead industrial complexes littering my shed walls, but nothing that would register on a Geiger counter. Scientist, engineer or other, it doesn't seem like a winning move to salvage this site. Those who salvaged all the left over response vehicles/aircraft (that have not been cancered to death that is) would likely agree.

    • Lady Ivy Vine XIII
      Lady Ivy Vine XIII 9 months ago +3

      @Mike Bell You fail to appreciate the ingenuity and stealth of humans. The sarcopagus was far from secure. Until that dome sent up, I can see a few determined souls braving both security and the radiation for that high value component.

    • Reza 20011380
      Reza 20011380 10 months ago +2

      @Mike Bell those stuff will probably be end up in underground auctions one day, imagine if someone took the actual control room 4 az 5 switch, just imagine how much would it be sold for?🤔

    • Mike Bell
      Mike Bell  Year ago +16

      Glad you appreciated the effort. The scavenged control room is a cool story. However sometimes the truth spoils a good story. multiple comments tell me it was impossible for radiation stalkers to access the control room. Security was impossible.
      I would think it us safe to say the staff who would have had legit access would conceivably have pocketed a few keepsakes for themselves. I would have. 😅

  • Blackshirt- D
    Blackshirt- D Year ago +1

    I’ve looked for a good video that could explain this accident well. I’ve never found one, until I watched this video. Excellent 3D graphics instead of 2d cheap schematics. Nicely done!

  • dB
    dB Year ago

    Interesting comment about the other reactors, I always wondered how Chernobyl colleagues kept them going during that meltdown.

  • Shane C.
    Shane C. 8 months ago

    Best explanation of this catastrophy so far! Well done!

  • H Kok
    H Kok 9 months ago

    I just saw three other presentations and this is the first one that really sticks. The speed of speech is just right, the animation is very well done and supporting the story.
    Maybe just explain the exact effect of poisoning and moderating and their differences

  • Luigi Fire
    Luigi Fire 4 months ago +1

    i saw the tv series and i loved it, because they explained everything in detail, i know the whole story by heart, but i like to watch stories about chernobyl, it fascinates me and i admit i would like to go there to see the reactor with a guide 😍

  • 765kvline
    765kvline Year ago +4

    One of the best documentaries on the actual process of the reaction and explosion.

  • simplycass
    simplycass 9 months ago

    Thanks for the video! It actually made so much sense to me and I’ve watched 4 other videos which left me confused. This one really helped me understand

  • Matt B
    Matt B Year ago +2

    This is brilliant. You are very skilled at capturing detail of a complex subject. The animation is stunning, and your narration is perfect.

  • Ways Otto
    Ways Otto 5 months ago

    Спасибо за рассказ, уважаемый автор не могли бы вы также подробно рассказать об аварии 7-го уровня опасности реакторов на Фукусиме-1 в Японии и сравнить эти аварии сделав анализ происшедшего и последствий . Было бы очень интересно посмотреть и сопоставить масштабы катастрофы, заранее благодарен Вам .

  • Brian
    Brian 11 months ago +1

    Great video w/ fantastic commentary.. it’s a powerful and impactful perspective on this disaster and mankind’s courageous response to step up!

  • Phil Rabe
    Phil Rabe 10 months ago +1

    Hey Mike, Love it! I fool around with Sketchup. I also do props for film so I noticed the 5 wheeled chairs in the control room model. They are anachronistic as seen in the actual photograph. (And I bet I am the only movie props person who also fiddles with 3D modeling that would ever notice)

  • René Monnier
    René Monnier 8 months ago

    Thank you for this very clear and concise presentation !

  • Coda Alive
    Coda Alive 9 months ago

    Mike Bell, good job again, didn't know you work at NPP. This is probably the best description of what was going on. Many still don't understand Chernobyl reactor was very different from anything West was using at the time, or uses now, beside it was partially military reactor producing tritium and probably plutonium. Even accident at Fukushima was predicted by several nuclear engineers because GE boiling water reactors are pretty dangerous. Tsunami was also predicted but private owners didn't care about warnings because it would cost money for building higher wall. Whole mess had to be nationalised by government; such companies are good until their assets make money but fail when they don't. Let alone after accident.

  • DrakoCrowley
    DrakoCrowley 10 months ago +1

    Here's my theory. The first explosion was a steam explosion that cracked the lid, allowing the Xenon to escape the core. Because of how many control rods were pulled out, the lack of Xenon meant there were so many neutrons flying about that the reactor went critical and a lot of Uranium atoms split all at once, causing a nuclear-type explosion.

  • VeracityLH
    VeracityLH Year ago

    Thank you posting this. It helped me understand better what happened...as far as we can understand. Great job!

  • leonardo baracchi
    leonardo baracchi Year ago +1

    I really appreciated the honesty!!
    Very rare when we come to certain topics.. Here in the west the attitude towards soviet stuff is usually awful.
    So I wanted to say that graphite has more than one good point, even if the lower enriched fuel is maybe the main one. And I think that the graphite reactors are now out of fashion for more than one reason but I think the first one is in fact chernobyl, and then I think that usa pushed very hard to have their main models used all over the world, with a non stop propaganda about pwrs...
    I think that the big problem with graphite is the positive void coefficient, but I would like to remind that many other designs have and had this peculiarity, and if we know we have to be careful with this, we also have to recognize that this is not an intrinsecally unsafe characteristic. USA pushed instead with their propaganda so that today most of the people think positive void coeff= intrinsecally unsafe.

  • Валерий Беляев

    Большое спасибо автору за атмосферное видео!
    Thank you very much to the author for the atmospheric video!

  • John Kern
    John Kern Year ago

    have you ever noticed that some of these nuclear reactor disasters are the result of the operators doing something stupid. The animation was fantastic! Show exactly what happened. You could actually see what was going on.

  • Patrick Graham
    Patrick Graham 7 months ago

    I’m a journeyman/ pipefitter by trade. I worked at the Vogtle nuclear plant in Georgia a few times. One time I was a few hundred feet from the containment building that houses the reactor. Chernobyl was always on my mind. So relieved when that outage was over

  • UnRuleD Grizz
    UnRuleD Grizz Year ago +1

    This animation was mind blowing. Nice job man. Rip to the Heroes who saved the world and risked their lives to ARP.

  • Darius Eisenhauer
    Darius Eisenhauer Year ago +1

    This is a really really great video. I just wanted to tell you that. It's easy to understand, full of valuable information and the graphics are awesome. Really good job. The only criticism would be that you didn't put any sources anywhere as far as I can see.

  • T J
    T J 11 months ago

    I feel like we should have paid for this content! This is the best visual explanation I have seen about the Chernobyl reactor explosion. My hat is off to you.

  • Jeffrey Holicky
    Jeffrey Holicky Month ago

    5:44 I have read and watched a lot on this subject and but your demonstration of the xenon poisoning and rationale on why they should not restart after it is poisoned, was extremely helpful. It was mentioned "as a matter of fact" in Wikipedia but more in a "scientific way" where we are all supposed to get it. Unless all the plant workers were trained nuclear scientists I cannot see how anyone working there would have a clue about this stuff. But evidence is clear that those that designed them for sure held critical operational information back - either from the get go or as issues at other plants occurred. Thanks for the video - well done.

  • PIXEL THE ALIEN
    PIXEL THE ALIEN 6 months ago

    Wow, that lid had to weigh a ton and it got flicked up in the air like a wine bottle cork…can only imagine what the other workers experienced. The horror movie they did on this had me terrified of this story as a kid.

  • Mike Bell
    Mike Bell  Year ago +305

    Corrections thanks to commenters:
    *The bottom control rods were not coupled with the AZ5. AZ5 only lowered the top rods. If the bottom rods had moved as animated the disaster would have been averted. No rod was inserted past 30%. see corrected video in the Russian version of this video thexvid.com/video/NeZScDZA_uY/video.html
    *There was a smaller first explosion followed by the main explosion approximately 2.5 seconds later. See thexvid.com/video/NeZScDZA_uY/video.html
    *It is not certain whether Akimov or Toptunov pressed AZ5. In certain accounts Akimov disconnected the servos to drop the rods faster.
    *The return loop from the turbines is indicated here. thexvid.com/video/NeZScDZA_uY/video.html
    *The 2,000 ton lid in this video is an error. The upper biological shield nicknamed "Elena" is about 1,000 tons. The upper biological shield was a steel casing filled with iron barium serpentinite cement stone (ZHBTSK). This material contains bound water and protects against radiation. Steel casing weighed 450tons. Volume of filling 15.3m diameter and 2.3m thick equates to 420m3 less channel piping @ 2kg/m3 is close enough to 1,000 tons.
    A3-5 is the Russian spelling for AZ-5...

    • Mike Bell
      Mike Bell  2 months ago

      @Yasser Alsamei nuclear power is highly complex. It is not able to withstand a wilful attempt to destroy it. This is the first time in history where nuclear power are in a large war and the outcomes are very uncertain and dangerous

    • Yasser Alsamei
      Yasser Alsamei 2 months ago

      Very interesting animation, however, if the video continued on the preventive measures developed to prevent re-occurrence, it could give the whole world a moment to breath that such disaster will not occur again in the world especially with what i noticed yesterday in Ukrayn. Can critical control system etc be impacted by external impact such as rockets etc. . what is the solution To tell them to stop fighting to save innocent kids and women !!!Think about it. Do we need to build more nuclear plants and assume probability of occurrence is low or robust system is there..please, please, please, reassess.

    • Cyberfunk
      Cyberfunk 3 months ago

      @Taras Wertelecki That is what is not known. The reactor was not supercritical so if the switch was the cause, the accident could have been avoided if the switch or reacter had been desinged differently or perhaps if the button had not been used and the control rods would have been inserted individually.

    • Taras Wertelecki
      Taras Wertelecki 3 months ago +1

      @Cyberfunk It matters little at any rate, the reactor was out of control and there was no way the operators could have prevented the explosion with or without pressing that switch.

    • Cyberfunk
      Cyberfunk 3 months ago

      @Taras Wertelecki It isn's so simple, thunderf00t has also done some analysis on it and had another theory.