Terminal Run

During the mid watch Zhou was accompanied by the helm officer at the helm console, a ship control officer at the port console, and a tactical systems watch officer at the starboard console. The other seats were empty, the chairs prevented from rolling around the room by a floor lock. The room seemed much too bright, suddenly. Zhou ordered the room lights switched to red, which was his usual mid watch preference, but sometimes it made him feel drowsy and he would fight the sensation with the room lit more brightly. In the red light, he felt more relaxed. He took out the pack of cigarettes, a popular White Chinese brand, and stared at it, telling himself he had to quit. But not this watch. He put one in his mouth and brought the flame to the tip, the smoke making him feel more alert. He exhaled and glanced at the sonar display on the command console, flipping screens from the broadband to the narrowband processors to the acoustic daylight imaging.

The sea behind them, to the north, was full of the angry thrashing screws of the task force. But other than the sonar traces from the convoy, the sea was empty. Of course, at the convoy transit speed of thirty-five knots, the flow noise of the water over the hull and the increased machinery noise from running at fifty percent reactor power would make detecting an unseen submarine in the sea impossible. The signal from such an adversary would be faint, the noise level high, and the signal-to-noise level below the minimum threshold for detection. It was insane driving ahead of the convoy like this, matching their speed, it made them deaf. There was an alternative — a gallop-and-walk tactic, which would allow them to slow to a five-knot sonar search speed to clear the seaway, then speed up to a greater velocity than the surface force to avoid being run over by them.

Except to average thirty-five knots, if he lingered at five knots for even ten minutes, his gallop speed would have to be forty-one knots, which would be a sonar search disaster, since any speed over thirty-nine knots required the reactor to be shifted to forced circulation. The intricacies of the reactor were not Zhou’s concern, since that was the domain of the comrade chief engineer, Leader Dou Ling, a stubborn grime covered bastard who acted as if he were in command of the Nung Yahtsu. But Zhou did know that rigging for forced circulation meant starting four reactor coolant pumps, each the size of a small truck, and the noise from the pumps was the loudest noise the ship could make. Not only would that risk detection by a Western submarine, it would make sonar reception completely impossible, and signal-to-noise ratio would crash. But then, the ten minutes would be worth it to allow the narrowband processors to check out the sea for a contact.

Zhou shook his head, knowing that the narrowband sonar processors were a gift and a curse in one package. They would require far more than ten minutes to integrate the sonar data from a small slice of ocean just ahead of them, the discrimination circuits requiring more like eighteen minutes per slice of ocean. With narrowband taking too long to be useful, a gallop and-walk could only use the broadband sonar, and in truth, a few minutes of reduced ambient and own-ship noise would be a beneficial thing for the broadband sonar. Accordingly, Captain Lien had ordered a five-minute drift at five knots for every hour, the remaining fifty-five minutes spent at thirty eight knots to allow the ship to average thirty-five knots. The next drift period had arrived at the top of the hour as the chronometer needle on the beautiful instrument Lien had donated to the ship came to twelve of three o’clock.

“Helm Officer, dead slow ahead, make turns for five knots.”

“Dead slow ahead, turns for five knots acknowledged, Leader Zhou.”

A bell rang at the helmsman’s console, the engine order telegraph. The ship would slow to five knots, and he, the tactical systems watch officer, the sonar officer of the watch, and the Second Captain computer system would scan the sea to search for the Westerners, despite the intelligence that indicated that the Americans were far over the horizon and the British were coming from the other side of the hemisphere.

“Sir, engine room answers dead slow ahead, making turns for five knots,” the helm officer reported.

Zhou nodded. “Very good.” He reached for the microphone at the command console. “Sonar Officer of the Watch, five knots, conduct a complete sonar search and report all contacts.”

“Sonar Officer, well received, conducting search.”