At any given moment, several of the US Navy’s Nimitz class aircraft carriers are sailing the world’s oceans. Weighing in at 90 thousand tons, these massive vessels need a lot of power to get moving. One would think this power requires a lot of fuel which would limit their range, but this is not the case. Their range is virtually unlimited, and they only need refueling every 25 years. What kind of technology allows for this? The answer is miniaturized nuclear power plants. Nimitz class carriers have two of them, and they are pretty much identical to the much larger power plants that make electricity. If we can make them small enough for ships, can we make them small enough for other things, like airplanes?
This week’s film begins as abruptly as the Atomic Age itself, though it wasn’t produced by General Electric until 1952. No time is wasted in getting to the point of the thing, which is to explain the frightening force of nuclear physics clearly and simply through friendly animations.
[Dr. Atom] from the Bohr Modeling Agency describes what’s going on in his head—the elementary physics of protons, neutrons, and electrons. He explains that atoms can be categorized into families, with uranium weighing in as the heaviest element at the time. While most atoms are stable, some, like radium, are radioactive. This evidently means it stays up all night doing the Charleston and throwing off neutrons and protons in the process of jumping between atomic families. [Dr. Atom] calls this behavior natural transmutation.
Artificial transmutation became a thing in the 1930s after scientists converted nitrogen into oxygen. After a couple of celebratory beers, they decided to fire a neutron at a uranium nucleus just to see what happened. The result is known as nuclear fission. This experiment revealed more about the binding force present in nuclei and the chain reaction of atomic explosions that takes place. It seemed only natural to weaponize this technology. But under the right conditions, a reactor pile made from graphite blocks interspersed with U-235 and -238 rods is a powerful and effective source of energy. Furthermore, radioactive isotopes have advanced the fields of agriculture, industry, medicine, and biochemistry.
This documentary from 1959 gives a satisfyingly thorough look inside a nuclear powered icebreaking ship called Lenin. This actually set a couple of world’s-firsts: it was the first nuclear powered surface vessel and the first civilian vessel to be powered thusly.
The ship was built to clear shipping paths to the northern ports of Russia. Testing of both ice and models of the ship design point to the ability to break ice layers that are two meters thick. This requires a lot of power as ice-breakers generally use their hull shape and gravity to break the ice by driving up onto it to bend the ice to the breaking point. The Lenin achieved this power using its nuclear reactor to heat steam which drove electric generators. The energy produced drove three screws to power the vessel.
Of course this was back in the day when control panels were substantial, which you can get a peek at starting half-way through the twenty-minute film. This includes a demonstration of the ship’s network of radiation sensors which alert the control room, and sound a local alarm when they are triggered. During it’s 30-year operational life the vessel had a couple of accidents stemming from refueling operations. You can find more on that over at the Wikipedia page, but stick with us after the jump to see the vintage reel.