# How much does an RBMK nuclear reactor weigh? **URL:** \ **Category:** Factual Questions\ **Created:** [August 26, 2012, 11:28pm UTC](https://boards.straightdope.com/t/how-much-does-an-rbmk-nuclear-reactor-weigh/632762 "2012-08-26T23:28:38Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![Ranchoth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ranchoth/32/1066_2.png) [@Ranchoth](https://boards.straightdope.com/u/Ranchoth)\ **Post date:** [August 26, 2012, 11:28pm UTC](https://boards.straightdope.com/t/how-much-does-an-rbmk-nuclear-reactor-weigh/632762/1 "2012-08-26T23:28:38Z")
As used at [Chernobyl](http://en.wikipedia.org/wiki/Chernobyl_Nuclear_Power_Plant)? Minus, that is, the weight of the turbine system, and the reactor hall building itself? I don’t need an answer _fast_, per se, but it’d be handy to have before I begin flight testing. Can anyone help me out? ---
**Author:** ![Airman\_Doors\_USAF](https://avatars.discourse-cdn.com/v4/letter/a/e36b37/32.png) [@Airman\_Doors\_USAF](https://boards.straightdope.com/u/Airman_Doors_USAF)\ **Post date:** [August 26, 2012, 11:31pm UTC](https://boards.straightdope.com/t/how-much-does-an-rbmk-nuclear-reactor-weigh/632762/2 "2012-08-26T23:31:18Z")
The specific answer to your question is that I have no idea, but flight testing? ---
**Author:** ![Nanoda](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Nanoda](https://boards.straightdope.com/u/Nanoda)\ **Post date:** [August 27, 2012, 4:05am UTC](https://boards.straightdope.com/t/how-much-does-an-rbmk-nuclear-reactor-weigh/632762/3 "2012-08-27T04:05:23Z")
I think Comrad Ranchoth is taking the [Tupolev Tu-95](http://en.wikipedia.org/wiki/Tupolev_Tu-95LAL) out of mothballs. Either that or he’s using misdirection to figure out the scrap value of some hot (hot) steel. ---
**Author:** ![tracer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tracer/32/20578_2.png) [@tracer](https://boards.straightdope.com/u/tracer)\ **Post date:** [August 27, 2012, 4:07am UTC](https://boards.straightdope.com/t/how-much-does-an-rbmk-nuclear-reactor-weigh/632762/4 "2012-08-27T04:07:22Z")
Maybe he’s playing a Champions [TM] session, and wants to know how much Strength it would take to bench-press a nuclear reactor. Either that, or he’s got a bar bet going to see if Superman would be strong enough to lift it. ---
**Author:** ![coremelt](https://avatars.discourse-cdn.com/v4/letter/c/4491bb/32.png) [@coremelt](https://boards.straightdope.com/u/coremelt)\ **Post date:** [August 27, 2012, 4:18am UTC](https://boards.straightdope.com/t/how-much-does-an-rbmk-nuclear-reactor-weigh/632762/5 "2012-08-27T04:18:41Z")
> [@Nanoda](#): > > I think Comrad Ranchoth is taking the [Tupolev Tu-95](http://en.wikipedia.org/wiki/Tupolev_Tu-95LAL) out of mothballs. Apparently we might still see (unmanned) nuclear aircraft one day. > **[Nuclear UAV drones could fly for months at a time](https://newatlas.com/nuclear-uav/22041/)** > > Nuclear-powered unmanned aerial vehicles (UAVs) that would increase operational flight durations from days to months are a technological possibility today, according to a feasibility study undertaken last year by Sandia National Laboratories and... I imagine these are using RTG’s and not reactors. ---
**Author:** ![Ranchoth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ranchoth/32/1066_2.png) [@Ranchoth](https://boards.straightdope.com/u/Ranchoth)\ **Post date:** [August 27, 2012, 10:58pm UTC](https://boards.straightdope.com/t/how-much-does-an-rbmk-nuclear-reactor-weigh/632762/6 "2012-08-27T22:58:31Z")
> [@Nanoda](#): > > I think Comrad Ranchoth is taking the [Tupolev Tu-95](http://en.wikipedia.org/wiki/Tupolev_Tu-95LAL) out of mothballs. > > Either that or he’s using misdirection to figure out the scrap value of some hot (hot) steel. Something [like that](http://en.wikipedia.org/wiki/Project_Pluto), if only on the simulator. And a wee bit larger. Of course, it’s a monstrosity that requires more than a _bit_ of artistic license, but I’d like to try to start from at least a _base_ of technical realism. ---
**Author:** ![tracer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tracer/32/20578_2.png) [@tracer](https://boards.straightdope.com/u/tracer)\ **Post date:** [August 28, 2012, 5:13am UTC](https://boards.straightdope.com/t/how-much-does-an-rbmk-nuclear-reactor-weigh/632762/7 "2012-08-28T05:13:19Z")
Nuclear-powered jet engines would be **awesome**. ---
**Author:** ![si\_blakely](https://avatars.discourse-cdn.com/v4/letter/s/d9b06d/32.png) [@si\_blakely](https://boards.straightdope.com/u/si_blakely)\ **Post date:** [August 28, 2012, 10:39am UTC](https://boards.straightdope.com/t/how-much-does-an-rbmk-nuclear-reactor-weigh/632762/8 "2012-08-28T10:39:26Z")
The RBMK reactor pit is 21.6×21.6×25.5m - total volume ~12000m[sup]3[/sup]. If filled with water, that is 12000 tonnes. Of course, graphite and uranium and zircalloy and stainless steel weigh more than water, so … Can 30MW raw thermal output lift 15000 tonnes (without any additional heat-to-work equipment)? Si ---
**Author:** ![coremelt](https://avatars.discourse-cdn.com/v4/letter/c/4491bb/32.png) [@coremelt](https://boards.straightdope.com/u/coremelt)\ **Post date:** [August 28, 2012, 11:08am UTC](https://boards.straightdope.com/t/how-much-does-an-rbmk-nuclear-reactor-weigh/632762/9 "2012-08-28T11:08:34Z")
> [@Ranchoth](#): > > Something [like that](http://en.wikipedia.org/wiki/Project_Pluto), if only on the simulator. And a wee bit larger. What does the weight of an RBMK have to do with this? Project Pluto and other nuclear rocket designs wouldn’t seem to have much in common with an RBMK. The weight of this would seem more relevant: > **[Phoebus](https://www.daviddarling.info/encyclopedia/P/Phoebus.html)** > > Phoebus was a series of nuclear reactors, designed and built in the 1960s as part of the Rover program, to meet the needs of an interplanetary mission. Phoebus 2 5000 Megawatts, 250,000 lbs thrust ---
**Author:** ![si\_blakely](https://avatars.discourse-cdn.com/v4/letter/s/d9b06d/32.png) [@si\_blakely](https://boards.straightdope.com/u/si_blakely)\ **Post date:** [August 28, 2012, 12:15pm UTC](https://boards.straightdope.com/t/how-much-does-an-rbmk-nuclear-reactor-weigh/632762/10 "2012-08-28T12:15:52Z")
Is it just me, or is it apposite that **coremelt** posts a link to nuclear rockets that seem to be sitting on the catastrophe curve between motive force and exploding radioactive vapour? A bit of research show that nuclear rocket engines could achieve thrust-weight ratios of 7:1 - more than I expected. Si ---
**Author:** ![AdamF](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/adamf/32/6246_2.png) [@AdamF](https://boards.straightdope.com/u/AdamF)\ **Post date:** [August 28, 2012, 4:53pm UTC](https://boards.straightdope.com/t/how-much-does-an-rbmk-nuclear-reactor-weigh/632762/11 "2012-08-28T16:53:13Z")
You may want to google “Heat Transfer Reactor Experiment”. Both working prototypes are on display in Idaho. IIRC, they both came under 100 tons.