Chernobyl, Unit 4 · April 1986
The Night Shift Test
A safety test planned for the afternoon slides toward midnight, with a different crew.
- Ages
- 13 to 15
- Time
- About 20 minutes
- Shape
- 3 decisions and a defense
Part 1 of 3 in the series Holding It Together
The situation
On 25 April 1986, the crew at Chernobyl's Unit 4 planned a safety test: could a slowing turbine power the cooling pumps for about 40 seconds until the backup generators started?
Some specialists knew the reactor had design weaknesses. That knowledge had not clearly reached the people at the controls. Then the grid controller asked the plant to keep supplying power, and the test began to slip.
Your teen traces the chain as a systems analyst, looking for the point where a small, cheap decision changes the most.
The background and the choices come from the historical record. What really happened is shown only after your teen writes a defense.
What it builds
Noticing when a plan's conditions change, and deciding when to pause and when to go on.
Using evidence
Backs each claim with a specific fact from the simulation.
Seeing ripple effects
Traces second- and third-order effects through the system.
Judging risk
Names likely and severe risks and how to reduce them.
Making a clear argument
A clear claim, reasons, and an answer to the best counter-argument.
Subjects it touches: History, Science, Engineering. It sits beside your core curriculum; it doesn't replace it.
Try the first decision
A short preview. It has no AI and saves nothing. Want two minutes with the background first? Try a mission free
Decision 1 of 3 · Preview, no AI, nothing saved
It is 2 pm on 25 April. The reactor is partway through lowering power for the test when the grid controller asks the plant to keep supplying electricity a while longer. The test was planned and briefed for the day shift. The next chance to run it is about a year away. You are the senior engineer.
Opening soon.
Accounts open shortly. Every student gets 15 free tutor messages, enough to try a mission. After that, $888 a year or $88 a month for one student.