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Uranium-Filled 'Lost Nuke' Missing Since 1950 May Have Been Found (bbc.com)
Although the U.S. government "does not believe the bomb contains active nuclear material," schwit1 shares this report from the BBC:
A commercial diver may have discovered a lost decommissioned U.S. nuclear bomb off the coast of Canada. Sean Smyrichinsky was diving for sea cucumbers near British Columbia when he discovered a large metal device that looked a bit like a flying saucer. The Canadian Department of National Defence believes it could be a "lost nuke" from a US B-36 bomber that crashed in the area in 1950.... The plane was on a secret mission to simulate a nuclear strike and had a real Mark IV nuclear bomb on board to see if it could carry the payload required...
The American military says the bomb was filled with lead, uranium and TNT but no plutonium, so it wasn't capable of a nuclear explosion... Several hours into its flight, its engines caught fire and the crew had to parachute to safety... The crew put the plane on autopilot and set it to crash in the middle of the ocean, but three years later, its wreckage was found hundreds of kilometers inland.
The crew says they dumped their bomb-like cargo into the ocean first to avoid a detonation on land.
The American military says the bomb was filled with lead, uranium and TNT but no plutonium, so it wasn't capable of a nuclear explosion... Several hours into its flight, its engines caught fire and the crew had to parachute to safety... The crew put the plane on autopilot and set it to crash in the middle of the ocean, but three years later, its wreckage was found hundreds of kilometers inland.
The crew says they dumped their bomb-like cargo into the ocean first to avoid a detonation on land.
Lost nuclear bombs are also called "Broken Arrow".
>the US Department of Defense has officially recognized 32 "Broken Arrow" incidents, including but not limited to
1950 British Columbia B-36 crash
1956 B-47 disappearance
1958 Mars Bluff B-47 nuclear weapon loss incident
1958 Tybee Island mid-air collision
1961 Yuba City B-52 crash
1961 Goldsboro B-52 crash
1964 Savage Mountain B-52 crash
1965 Philippine Sea A-4 incident
1966 Palomares B-52 crash[6]
1968 Thule Air Base B-52 crash
1980 Damascus, Arkansas incident
https://en.wikipedia.org/wiki/...
Uranium is nearly twice as dense as lead. The test run was apparently to "see if it could carry the payload required" which means you'd want the right weight/size/shape. They took the most dangerous bit out, at least.
systemd is Roko's Basilisk.
When you get to the point of heavy metals (such as the uranium in this instance), you start running into problems with simulating stuff made from them - you cant have a precise physical replica because the weight will be off, and quite often you cant add more mass because then you have something that is physically larger than the original.
In aircraft, weight and balance issues can affect performance considerably - so when you need to run simulation flights to test performance you couldnt really get a truly accurate result if you used a replica as it would either be too light or it would put weight in the wrong place on the aircraft due to the increase in size. You cant add ballast outside the weapon for the same reasons.
So the only way to run these tests back then was to use a proper weapon. Of course the core was removed, but on these aircraft they were always removed for take off, landing and cruise - a crew member literally had to insert the core into the weapon en route because the safety systems were still not trusted at that point, so keeping the core on board but separate would still result in an accurate test flight.
Edit: Other sites are reporting this was a dummy bomb packed with lead. No idea why a dummy would have uranium, maybe BBC is in error.
In any case it wouldn't be the fissile variety. Depleted uranium is still toxic, though.
How can I believe you when you tell me what I don't want to hear?
No, the lead was a simulator for the plutonium pit. The Depleted Uranium tamper surrounding the weapon isn't particularly radioactive. The tamper is there for two reasons, one the density and high inertia of it confines the chemical explosion long enough for the nuclear reaction to occur. Secondly, fast neutrons from the plutonium chain reaction then cause the tamper to fission, generating another portion of the weapon's energy.
As to why you're flying the aircraft with a weapon such as this, it's because it is supposed to be a live training mission, testing all the electrical interfaces, mission profiles, etc... and without the plutonium pit, the weapon is inert from a nuclear perspective. At that point, they also didn't have really viable simulators that could be used as a proxy.
...si hoc legere nimium eruditionis habes...
While you can't trust the military to report honestly to the public on an accident, in this case there is every reason to believe this bomb is quite safe. The Mark IV bomb had a hinge on it so you can open it up and load the fissile pit into it in flight, during an actual bombing run.
During a training mission there would be no reason to have the fissile pit on the aircraft.
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Read the summary again. It wasn't a "dummy" bomb, it was a real Mark IV nuclear bomb.
What it didn't have was the fissile core loaded. Which is exactly what would be expected; the Mark IV was designed to have the core loaded into the bomb by the aircrew during the flight.
So, it certainly wasn't a dummy bomb; it was a real Mark IV, with the normal uranium and TNT in the casing. But it almost certainly wasn't a live nuclear bomb, because there would have been no reason at all for the plutonium core to have been loaded on the plane, and even if the plutonium was on the plane, no reason at all for the aircrew to load the plutonium into the bomb.
Real bomb and no plutonium core.
It makes no sense to use a simulated nuke shape that actually has a radioactive, dangerous, and expensive restricted component when it can easily be simulated by replacing it with a safe, inert, and cheap substance.
They removed the plutonium core (which is radioactive and expensive), and only had natural uranium, which on its own is none of those things (well, technically it's radioactive, but only barely. You could eat it without getting radiation poisoning. It'd kill you from heavy metal poisoning, but not radiation). Hell, you can buy it off Amazon. It's also almost twice as dense as lead, so you can't simulate it with lead (and anything close in density is fantastically rare and expensive, like platinum and gold). Not sure why they'd have TNT inside, though maybe they wanted to make sure it wouldn't explode during the transit process.
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
So this highly radioactive core is still at the bottom of the ocean somewhere?
If this was in fact a training mission then the radioactive core would not likely be on board. That is a very expensive and militarily sensitive part of the weapon. The rest of the weapon, the nearly 5 ton case, while still an expensive and sensitive piece of equipment is not nearly as easily lost, stolen, or capable of being simulated for a training mission.
Also, the plutonium used in the core has a half life of over 24000 years, not something many would consider "highly radioactive". Such material is regularly handled with only gloved hands, which is what the crew would have to do to arm the weapon while in flight.
I am armed because I am free. I am free because I am armed.
No, just because it was a B36 - it would've been more surprising if at least one engine didn't catch fire. The B36 had propellers in pusher configuration on the trailing edges of the wings to reduce turbulence in the leading edges and improve lift. This required the radial engines be flipped front-to-back relative to how they were designed to be installed. This meant that the carburettors had cold air passing over them rather than air that had been warmed by passing over the engine, leading to ice build-up. This caused fuel to somehow come out of the carburettors the wrong way, make its way onto hot parts of the engines, and catch fire. The B36 was infamous for engine fires thanks to this highly questionable piece of engineering.
You do realize there's a difference between weapons grade, enriched uranium and depleted uranium, right? To accurately gauge the weapon carrying capabilities, it would be loaded with a "dummy load" which means no actual nuclear fuel. It gets loaded with depleted uranium to match the mass and weight distribution. In other words, the small ball of plutonium that actually makes the giant kaboom, isn't on the plane. (i.e. everything but the core. "In tonights test, the part of plutonium will be played by a ball of depleted uranium -- because we have a lot of that shit laying around.")
My question is, why would a dummy bomb be packed with TNT?
Its not actually a "dummy", but a real bomb with the core removed.