"Artist's rendering shows how Command Service Module (CSM) will dock with the Orbiting Workshop (OWS) during the Skylab mission. Assisting in the docking is the VHF Ranging System designed and built by RCA Government Communications Systems, Camdem, N.J. The system provides the CMS pilot with the range between the two spacecraft. Ranging is performed by sending radio tones from the CSM to the workshop, which retransmits them to the CSM. The range is determined by measuring the time between the transmission of the tones and receipt of the OWS retransmitted."
So, I’m reading about SL-1, so you will be subject to that today. Buckle up!
The SL-1 (stationary low-power reactor #1) was a boiling water reactor at the Army base located in Idaho Falls, Idaho, which was the home to many other Army reactors. It exploded on January 3rd, 1961 and killed it’s three operators.
I am learning most of the facts about this accident by reading Atomic America by Todd Tucker. This book talks about how the Navy’s success in building nuclear submarines (spearheaded by Admiral Hyman Rickover) created the fear that the Army would become obsolete if it did not convert to nuclear power. SL-1 and similar types of reactors would eventually be used to power remote army bases.
There are a couple of notable ways the Army really, really fucked up.
Like the nuclear reactor for the submarine, SL-1 had to adhere to some very strict guidelines that are not really standard of other reactors because they have to fit inside something. Size is an issue, it has to be able to be assembled on site, etc etc etc.
So, the fuck-ups.
1. SL-1 was a boiling water reactor, as opposed to a pressurized water reactor. Most nuclear reactors today are PWRs, because they’re safer. PWRs operate with a two-loop system. Even though the water inside is heated to well above its boiling point, the immense pressure inside the reactor keeps it in liquid form so that the reactor components are always coated with water. But, notably, the water does not touch the fuel or anything. Here is a photo.
This prevents the steam that’s eventually released from becoming radioactive. But, it requires a lot more equipment, space, money, etc. this is the kind of reactor they used to build the nuclear submarine.
A BWR is a single loop system in which the water is basically pumped straight into the reactor core to be used as a coolant, and when it evaporates because of the heat, that radioactive steam is directly used to power a turbine.
The layout of this reactor was also…hm…bad. Like I get it, nuclear power for energy and not just destruction was relatively new. Gotta learn from something. But Jesus fucking Christ.
There were only five control rods, or reaction moderators, which is suitable for a reactor that small. But the way the fuel channels were organized, close to the center, it gave the control rod in the middle WAAAAY more power than the other four combined. All of the control rods also had a history of sticking inside the reactor, because the channels were lined with boron strips which were designed to moderate electron flow (and prevent the reaction from getting out of control), but the tack they were put on with started to fail almost immediately, and the boron started to flake off and melt, which actually made the core more radioactive because the “poison” was no longer there as a built in reaction moderator.
There was also no containment building.
AND! To top all this off. The reactor was started by manually lifting that super-powerful control rod to start the reaction. But y’know. If you’re off by even an inch, the reaction runs away, because the design of this reactor was SO BAD
So. Yeah. Our boy Jack Byrnes lifted the control rod. The reaction was critical in 380 milliseconds (criticality is the aim, just a self-sustaining-enough reaction to generate power). He pulled somewhat more than what was required. The reactor immediately enters prompt criticality (BAD, a self-sustaining UNMODERATED reaction). All the water in the bottom of the reactor instantly flashes into steam, which propels all the water on top up into the lid at something like 10k pounds/sq in of force. One of the control rod plugs impales Richard Legg, who had been standing on the reactor lid, through the groin, and comes out his shoulder, which pins him to the ceiling.
Byrnes and Legg are dead. McKinley, the third operator and the newest and youngest there, is critically injured, but effectively doomed. The force of the steam explosion was what killed them, and it was so powerful that the many-ton reactor that had been literally welded into the ground jumped nine feet.
It takes six days to get Richard Legg off the ceiling, because the ensuing meltdown produced so much radiation that workers could not stay in the room longer than a minute without exceeding their yearly radiation dose limit. In that entire time, his body is so radioactive that it doesn’t decay at all.
-cracks knuckle- Okay. Before I get into this, please read the tags.
That being said.
Tobias Buckell, I have a huge fossilized bone to pick with you.
In the book Envoy, it's mentioned that a HAVOK thermonuclear device has been repurposed by colonists to power their settlement, and is then repurposed again to power an EMP. I haven't read the book, and the synopsis on the Wiki was sparse, so apologies if I got the details wrong; it won't affect what I'm gonna say.
Things to know: Fission is the splitting of atoms by a neutron. Fusion is when atoms combine. Both release a lot of energy, but fusion is by and far away the more powerful of the two.
Firstly, nuclear weapons emit an emp without being repurposed. It's just what they do.
Secondly, while the fuel of a nuclear device can be used to power a reactor, you CANNOT just crack open a nuke, however carefully, and plonk the uranium or plutonium (or both, depending on the device) into a reactor. It is SO much more complicated than that.
Firstly: Reactor fuel, while enriched, is nowhere NEAR as enriched as weapon fuel. Also, enrichment refers to the concentration if a specific isotope of U or Pu, not how elementally pure it is. ²³⁵U and ²³⁹Pu are the isotopes found in weapons grade fuel, with the uranium being 93% ²³⁵U. Reactor grade fuels are composed mostly of ²³⁸U (about 80%, with approx. 20% being ²³⁵U) and Pu of a variety of mixed isotopes.
And like...I don't think most people know just how ungodly goddamn terrifyingly dangerous weapons-grade fuel is. These metals are ACTIVELY TRYING TO KILL YOU by this point. Plutonium can fucking spontaneously fission or, yknow, just. Catch fire. For no reason. Once a mass of Pu or U gets to a certain point, neutrons can't escape and the fission becomes self sustaining. This is the tipping point, or Critical Mass.
Even the SHAPE of the fuel matters A LOT. Yes, there are Bad Shapes when dealing with weapons-grade fuel, ESPECIALLY Pu. Bar? Billet? Ring? Yes, good. You can have a critical mass in these shapes and not kill yourself. Sphere? Better be a fucking small one. And even then, if you so much as drop something on a softball-sized sphere of Pu, you will die. 3 scientists found this out the hard way while conducting experiments on the infamous Demon Core.
Shit, even Pu IN SOLUTION can and HAS killed simply because some poor sod turned on a mixing kettle, and the vortex created pushed enough Pu solution close enough together that Cecil Kelly died a very, very bad death after only thirty-four hours. By contrast, the victims of the Demon Core lasted days and weeks, and people present at Chernobyl lasted weeks, even YEARS after exposure. These events are called criticalities, or, in a reactor, a power excursion.
On to mechanisms. Weapons first.
A thermonuclear device actually uses two phases, both fission, to set off the fusion reaction.
The implosion type fission explosive puts pressure on another fission device that contains the fusion fuel. Boom. Micro-star.
For reactors, the fuel is compressed into pellets, and then loaded into tubes called fuel rods. These rods are then loaded into a reactor core, where they generate heat that boils water and the steam turns turbines.
As Chernobyl (and SL-1) show, a reactor is capable of a devastating explosion. However, by weapon standards, the explosion is considered a 'fizzle'. This is because of the low enrichment of the fuel pellets compared to weapon fuel. Also, the mechanism of explosion is different in a reactor, depending on the type (Light Water, Pressurized Water, and Liquid Metal reactors). PWR reactors, the most common type, the aformentioned explosions, while differing in some details (core size, condition of the core, and core status at the time of the excursion) were both caused by some, or multiple, jackasses removing control rods from the core. This meant that (and I'm summarizing in the case of the Chernobyl RBMK reactor) the fission became self-sustaining, which flash boiled water, which then caused a steam explosion. (Fun fact: the SL-1 reactor experienced an excursion that peaked at TEN MI L L I O N PERCENT above what the reactor was designed to produce. The wiki article is WILD.)
All down to operator error.
Now, LMFR reactors (Liquid Metal Fast Reactors) use molten metals as the coolant. They have higher power density, are very compact, and actually in use aboard nuclear subs and aircraft carriers. They use the same fuel as a BWR.
Next: Megatons To Megawatts and Breeder Reactors (I see you kinky bastards, you sit the fuck down.)
So, theoretically, yes, weapons fuel can be turned into reactor fuel. If you know what the fuck you're doing and have all the correct, highly specialized equipment. Weapons-grade fuel has to be downblended, or mixed with natural uranium to the 20/80 ratio of ²³⁵U/²³⁸U. And reactor fuel can be used in weapons. This is where breeder reactors come in (SIT. DOWN.) A breeder reactor makes more fuel than it consumes by reacting Uranium into reactor-grade Pu, which is a mixture of isotopes. This can be used in weapons, but the yield is. Paltry, with a high chance of a fizzle.
So. Unless these fucking colonists were a bunch of nuclear goddamn physicists and nuclear engineers who just HAPPENED to have the parts for a LMFR just lying the fuck around, AND the equipment, materials and know-how to downblend AND THE RE-FUCKING ENRICH the original weapon fuel (Both of which, by the way, can take FUCKING MONTHS) there is no way in all seven goddamn circles of H E L L that a HAVOK could be used to power a city.
Tobias Buckell, I am going to put so much pudding in your underwear.
So many legos on your floor.
I am going to haunt the living AND dead shit out of you.
The Skylab Airlock flight article 2 lower deploy assembly being loaded into the Guppy, in front of McDonnell Douglas Blg 66 ready, to be transported to the Kennedy Space Center, Florida.
