ATK Thiokol Space Shuttle static rocket booster at night. User KMF12 writes to say he was the back-up mechanical engineer for this motor (FSM-13), and one of his duties was to make sure that the motor cools down properly. Aside from quenching the motor with CO2 through the forward and aft openings, we also use a "sprinkler system" to cool the motor from underneath. The first 3 segments (forward, center-fwd, and center-aft) usually cool down after 20-30 minutes, while the last segment takes a minimum of 3 hours. After then, we can put the house/bay back on top of the motor. Recorded 11/16/2006