360° panorama by Matthew Normand.
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Forward engine room of the World War II era Gato class submarine USS Drum (SS-228). Two of the four Fairbanks-Morse diesel engines on the boat are housed here. They generated electricity to power ship's service electrical loads, propel the ship via the electric motors the spin the boat's two props, and charge the battery so the boat can operate underwater. The battery supplies all electrical power while submerged.