Voyage of the Devilfish

The USS Billfish cruised slowly northeast at four knots, bare steerage way, at a depth of 658 feet. The ship was rigged for ultraquiet. All offwatch personnel were ordered to their bunks. Lights throughout the ship were off or switched to a dim red setting. The P.A. Circuit One speakers were disabled, an announcement on them might be detected outside the hull. In each space men stood with headphones and boom microphones, linked on a single ship wide phone circuit, ready to pass urgent orders by voice. Every running pump or piece of equipment in the ship had redundancy; the equipment selected to be running was (he one in a set that was the quietest. All maintenance activity was halted. Non-essential gear such as galley equipment was turned off — the crew would eat cold meals for the duration of ultraquiet. Hard-soled shoes were prohibited, the crew had switched to sneakers and slippers. Stereos, radios, televisions were turned off. The spare gyro was shut down, as well as the Bomb, the oxygen generator. Reactor main coolant pumps were in slow speed. The ship was dead quiet. In the torpedo room all four tubes had signs on the inner doors reading WARSHOT LOADED. Tubes three and four were flooded, sea pressure equalized to the outside pressure, outer doors open and weapons powered up, their gyros spinning rapidly, their computers activated, ready for a firecontrol solution. In the control room only the whine of the gyro and the humming of the firecontrol computer were audible. The watchsection firecontrol team was ready to track and, on orders, shoot any contact.

Lieutenant Culverson, the Officer of the Deck, stood on the Conn and stared at the sonarrepeater console, a television screen covered with red filter glass. A heavily built Texan with a string tie around the collar of his blue poopy suit, Culverson wore a pair of blue Hush Puppies loafers. After all, the rig for ultraquiet had deprived him of his usual cowboy boots. Culverson, wearing red goggles to preserve his night vision in case the ship needed to come to periscope depth, stared at the sonar screen, straining to find a submarine in the mass of stringlike indications of random ocean noises and biologies. Twenty feet aft the sonar space was rigged for black, with only the six sonar console screens showing light in the room. Sonarman Chief Dawson sat at the central console of the sonar panel, the space silent except for a faint high pitched whine from the video screens. The center lower screen was tuned to the athwartships beam of the towed sonar array, a set of hydrophones towed astern on a mile long cable. The beam examined a thin slice of ocean, looking for specific frequency tonals from an AKULAclass attack sub that COMSUBLANT Intelligence had predicted would come into the Billfish’s patrol area. The central console graphs were displaying the frequencies surrounding the anticipated 314-hertz tonal of the AKULA’s turbine generators.

As Dawson watched, the graph slowly grew a narrow hill in the center. The minutes clicked by, and the graph’s peak, the hill, became a mountain, then a pillar, then a thin sharp spike. 314.0 hertz. Exactly. Too clear and sustained to be a natural phenomenon. Dawson flipped through the other displays. One harmonic of 154 hertz was also spiking. With a 314 and a 154, it had to be an AKULA class. Dawson selected the LOFAR display, the low frequency analyzer that examined a contact’s screw pattern. The lines of frequency were showing the repetitious vibrations of an eight-bladed screw. It all added up to a Russian AKULAclass attack sub where it had no business being—150 miles east of Norfolk, Virginia. Dawson keyed his microphone.

“Conn, Sonar, narrowband contact Sierra One, bearing either three five zero or one seven zero, is a submerged contact, Russian nuclear type four, probable AKULA class, making three zero turns on one eight bladed screw. Recommend coming to course… zero three zero to resolve the bearing ambiguity.”

“SONAR, CONN, AYE, WAIT.” Dawson switched the display to the broadband waterfall, the display of all frequencies in the ocean around them. He concentrated on the two possible bearings to the narrowband contact. There was the beginning of a trace at 350. He put his palm on the cursor ball set into the horizontal section of the console and rolled it, moving the computer cursor to the trace, thereby tuning his audio set to that direction and that direction only. He shut his eyes, listened. What he heard was static, white noise, like rain, or water flowing in a creek. Broadband noise. He cut in a filter, removing the lower frequencies. He selected higher and higher frequencies and waited. Finally he heard it. poosh… poosh… poosh… He dialed in a higher frequency and listened. roosh… roosh… roosh… Still higher. floosh… floosh… floosh He turned up the volume. The new Russian reactor coolant pumps on the AKULA class made that sound. FLOOSH … FLOOSH … FLOOSH … He keyed his mike.