"Xenon got us now." GETR

GETR, the great General Electric Test Reactor.

It was a great test reactor and it operated from about 1959 for over 10 years before it was permanently shut down based on some seismic games.

Anyway, in the course of operating, questions arose on the need for rapid shutdown in the case of loss of secondary water flow. (To keep stuff brief, I'm not going into the plant hydraulics.) Just prior to the planned shutdown for refueling, the staff settled the questions on the need for fast response to loss of secondary flow as follows:
1. Secondary flow was turned off with GETR at full power.
2. The reactor operator observed the game, but otherwise did nothing.
3. With secondary flow off, the primary system temperatures increased and the power level decreased.
4. After a while the reactor operator announced, "Xenon got us now."
5. At that point, the six control rods were inserted and the scheduled shutdown activities began.

Aside from the above, following are two photos of plant engineer, Don Hughes, in action during the construction of GETR during 1958.