In this episode of Computers of Chornobyl series, we will talk about the mighty SKALA system, that controlled the RBMK reactors.
This is the first-ever documentary about its design, architecture, operation, and software. It also tells the story of how it was preserved for posterity and reveals, what is common between it… and a control computer of Apollo spacecrafts.

It took us nearly half a year to collect the information and technical details about SKALA computer, and what we uncovered has completely reshaped our understanding of how the Chernobyl Nuclear Power Plant operated. We sincerely hope you will enjoy it and learn as much as we have!

What you will find in this episode:
00:00 – Introduction
01:20 – How we saved SKALA
02:16 – This is why a special computer is needed to control a reactor
03:00 – A brief history of SKALA creation
04:00 – What is inside?
05:00 – This is what we discovered in archives
06:58 – Architecture and principles of operation
07:58 – A quick look to software of SKALA
09:00 – DREG and PRIZMA programs. Multi-machine mode.
11:15 – Control panels of DIVT engineer. Request devices.
12:49 – Reactor control room controls – mnemonic displays, selsyns, loggers
17:55 – The truth about the last signals of reactor 4.
19:55 – How DREG program worked.
21:14 – DIIS-2000 – SKALA’s sister computer system
22:33 – Outro

“They need constant cooling. Which is possible only if there is electricity. If it is not there, the pumps will not cool. As a result, the temperature in the holding pools will increase,” the agency said.