S-II: Meaning (information, definition, explanation, facts)

The S-II was a Saturn rocket stage.

Saturn V S-II (Second) Stage

"This cutaway illustration shows the Saturn V S-II (second) stage with callouts of major components. When the Saturn V first stage burns out and drops away, power for the Saturn was provided by the S-II (second) stage with five J-2 engines which produced a total of 1,150,000 pounds (5.1 MN) of thrust. Four outer engines are placed in a square pattern with gimbaling capability for control and guidance, with the fifth engine fixed rigidly in the center. "