The sign by the Polaris missile. It reads
Polaris was a deterrent and retaliatory missile specifically
designed for launch from a ballistic missile submarine while submerged (or
surfaced) to strike a target some 1,500 miles away. A typical submarine
carried 16 of these missiles which could all be launched within 15 minutes with
target information programmed in as little as 30 seconds. The missile would be
launched vertically from below the surface of the sea by a charge of compressed
air from its launch tube.
Polaris was powered by a solid fuel rocket engine and solid
fuel booster with a thrust of 100,000 lbs. After being fired from the
submerged submarine, the missile would leap into the air where its inertial
guidance system would take over. It carried a nuclear warhead.