The failure modes were already known before the disaster. They were kept secret from the rank-and-file reactor operators and supervisors, as the Soviet regime w

The failure modes were already known before the disaster. They were kept secret from the rank-and-file reactor operators and supervisors, as the Soviet regime was loathe to admit they were imperfect in any way. The monitors and failsafes were there. Maybe could have been better, but they would have worked had they not been disregarded and deliberately overriden. It was completely preventable. RBMK reactors of the same design are still operating safely today.