The swell broke over the heaving deck of the submarine. Reaching behind him, Seaman Martin took the five inch round from the feeder, cradling it in his left hand and steering it with his right, into the waiting breech of the cannon.

“Loaded” he called out over the reports from the small arms in the conning tower. He pulled his hands back quickly, as Petty Officer Third Class Beck slammed the breech shut, yelling “Locked. Gun Ready!”

The gun director, Lieutenant, Junior Grade Moretti, took one last look at the trajectory corrections he’d dialed in since the last round, and looked at the gunner. As the bow of the boat reached the top of the swell again, and paused for a moment before beginning to go down again, he slapped the gunner on the back, yelling “Fire!”

The five inch gun went off with a report that momentarily robbed the breath from everyone topside of the submarine. Heading away from the ship, the shell ripped through the air, sounding fainter. Seaman Beck jerked the breech open and the spent casing, now smoking, clanged to the deckplates and bounced overboard.

Three thousand yards downrange, the shell tore through the teak deck of the Kobyashi Maru, penetrating through the cargo hold and into the boiler room before detonating. As the shell exploded, it pierced the boiler of the now-doomed freighter, venting 1,200 PSI steam into the engine room.