ansatuofi
4 HN mentions · mentioned in 4 months, 2015–2025
1:33:11 · 265K views · Mar 5, 2013
A long documentary-style film on the 1961 SL-1 reactor accident, where a control rod was withdrawn too far and the reactor went prompt-critical. The resulting steam explosion ejected control rods and shield plugs.
HN links it in nuclear safety and military reactor discussions as the full story of the only fatal US reactor accident.
4 comments from Hacker News
First, a containment structure[1] is a key feature in any reactor[2]. These are massively over-engineered specifically to contain even unlikely problems. We learned that this was important after the SL-1 accident[3]. As you suggest, this is a feature designed to fail safely - the containment should keep the rest of us outside the building safe, and doesn't say anything about what happens to the stuff in side. > meltdown This term is thrown around a lot, and while solid fuel melting in a traditional reactor is a serious event, a lot of people seem to think that "meltdown" is some kind of terrible or damaging event. The reason people in the nuclear industry panic over a possible meltdown has little to do with safety; up until that point you could - in theory - still reasonably believe that the reactor could be fixed and (eventually) restarted. After a meltdown, you have to assume the core is trashed and is now a financial liability instead of your main source of revenue. Meltdowns are a terrible event financially. The actual melting of the fuel involves the passive-safety, which are usually designed to drain that fuel into (multiple) areas where it can cool down without criticality risk. All of this is still discussing very old features. This is like worrying about today's computers because vacuum tubes are fragile and need to be replaced when they burn out. Modern reactor design is very different, because we learned form the problems that happened in the original designs, just
> it makes me feel as if that system was designed by software engineers SL-1 feels as if it was designed and operated by Kerbals. TFA actually does mention the reactor and the accident > SL-1, a stationary low-power nuclear reactor in Idaho, blew up during refueling, killing three men. but that barely hints at just how eye-widening the whole saga was: this video To be fair, it is apparently considered likely that the overextraction of the rod was a deliberate murder-suicide. But yes, it seems that there's a reason that the US Navy still has a nuclear power program and the Army doesn't ( [LINK] seems good; I am not an expert).
The SL-1 story is well known in the industry. The Atomic Energy Commission has a video.[1] SL-1 was an experimental reactor at the National Reactor Testing Station in Idaho, an 8000 square mile AEC reservation. It's an isolated area, and the test reactors were many miles apart, just in case. [1] this video
Over on the nuclear side there was SL1, which AFAICT is probably the answer to the question "why doesn't the US Army have its own nuclear systems?" this video .