USS Indiana, SSN 789, “the Battle Bass”
Virginia-class fast-attack submarine
Barents Sea
2024 local time
Hey, Supe, I think I got something,” Sonar Technician Second Class Xavier Harris announced, craning his head to look back over his shoulder at the sonar supervisor on watch, Chief Schonauer.
Schonauer slipped into the chair at the workstation beside Harris. “Broadband or narrowband?”
“Narrowband—a 151-hertz signal, bearing zero-two-one,” Harris said.
Unlike previous classes of U.S. submarines, the Virginia class had done away with the separate sonar shack. On the Indiana, the sonar operators stood watch in the control room alongside the fire control technicians, quartermaster, pilot, and copilot, and the officer watches. Together, this multidisciplinary team formed the section tracking party, a watch team specifically organized to find and track adversary submarines. Harris hadn’t served on an LA- or Ohio-class boat, so this was all he knew. The chief often talked with nostalgia about his previous tours and loved telling anecdotes about the antics that went on in “the shack.”
There were days Harris wished sonar was separate from the conn, but having everyone in the same room certainly had advantages. As an ST2, he was a junior watch stander, but on the Indiana, that didn’t mean his observations and insights weren’t valued. Being valued was probably his favorite thing about his job . . . That and getting to go on liberty in foreign ports. He was still a few months from pinning on his dolphins, and once he had his “fish,” the respect his shipmates had for him would level up considerably. In the submarine community, competency was the only currency that mattered. Earning his warfare pin meant everything.
“Signal-to-noise ratio is good,” Chief Schonauer said, mirroring Harris’s display on his terminal and slipping on a pair of headphones. “Anything to correlate on that bearing?”
“No,” Harris said, barely able to contain his excitement that he might be the one to find their mission target—a new Russian submarine called the Belgorod that nobody had ever tracked before.
Schonauer announced the new contact.
“Conn, Sonar—new narrowband sonar contact designated Sierra Seven, bearing zero-two-one. Possible submerged contact in the vicinity of where intelligence indicated our target of interest could be,” Schonauer announced while looking at the OOD, the officer of the deck.
“Schonar, Conn, aye,” acknowledged Lieutenant Commander Yu, the OOD, riffing off the sonar supe’s last name while impersonating Sean Connery’s iconic accent.
No matter how many times the OOD did this schtick, Harris couldn’t help but laugh. Yu was the navigator on the boat, and he was funny as hell. If there was one thing that made life bearable on deployment, it was a sense of humor. Well, that and pizza night. The cooks on 789 could make a mean pizza when they tried.
The OOD and the contact manager, an experienced female junior officer named Lieutenant Crystal, who everyone called Crystal Light, stepped over to caucus with Schonauer.
“Where’s the ACINT, dude?” Crystal said, looking toward the port rear corner of control where the acoustic intelligence rider usually camped out.
“I think he went to the head, ma’am,” Schonauer said.
“Of course he did,” the OOD said, “because that’s the perfect place to be when we get a new submerged contact.”
“Do you want me to go find him, sir?” the control room messenger asked, taking initiative.
“Check crew’s mess first,” the OOD said. “He’s been gone awhile. Five bucks says he’s playing cribbage.”
The messenger shot a finger pistol at the OOD and said, “My thoughts exactly.”
“I can search the acoustic database, sir . . . if you’d like,” Harris said. As far as he was concerned, they didn’t need outside ACINT.
Anything that dude can do, I can do, Harris thought with more than a little irritation. Just another rider taking up a bed so more of the crew has to hot rack.
“Hop to it,” the OOD said and then walked back to the command workstation in the middle of the conn.
Lieutenant Crystal, whose job was succinctly defined by her title of contact manager, stayed. Schonauer leaned in, too, and they became a three-body investigative huddle as Harris opened the ASD, or acoustic signature database, that ONI maintained. The ASD was made for submarines on deployment by other submarines on deployment.
“What’s that?” the junior officer of the watch, a brand-new and unqualified ensign fresh on the boat, asked after walking over.
“Well, sir, you know how every human being possesses a unique set of fingerprints?” Schonauer said as Harris entered “151 Hz” into the query window.
“Yeah,” the ensign said.
“Well, every submarine has a unique acoustic fingerprint. If one of our sister boats has encountered this 151-hertz signal before in the Barents Sea, it will be logged in the ASD. The intel guys at ONI sift all the data, correlate it, and try to identify the exact model and hull number of the submarine with that frequency vulnerability,” the sonar supe said. “ST2 Harris is looking to see if we can ID the Russian boat we’re tracking as Sierra Seven.”
“Cool,” the JOOW said.
The computer thought for a second, then populated a list of hits at 151 hertz.
“Must be a popular frequency,” Crystal said.
“You’re going to want to refine your search, Harris,” Schonauer said.
“I found the rider,” someone announced with bravado, and Harris turned to see the messenger strolling onto the conn with a red-faced ACINT specialist in tow. “He was in crew’s mess playing cribbage with Fitzpatrick.”
Good-natured public ribbing was another central tenet of submarine life.
“Sorry,” the intelligence specialist said, looking at his hands. “Just needed a brain break.”
Harris resisted the urge to roll his eyes. Yeah, because you were working so hard in the corner.
“Hop on over there and take a look at what ST2 Harris found,” the OOD said, leaving it at that. “I’m gonna give you guys a couple more minutes, then I’m turning.”
Harris had logged enough hours on watch to understand the unspoken meaning in the OOD’s statement. Everything in undersea operations could be distilled down to geometry. Driving a submarine was, basically, math. Since they’d acquired Sierra Seven on narrowband, the OOD had maintained a constant course and speed. That was great for sonar techs like Harris, because in this current geometry, the Indiana’s TB-29C towed array had a strong lock on the signal. The problem, however, was that with only a single leg of bearings from the emitter, the Indiana had an incomplete tactical picture. The target could be close, or it could be far away. It could be driving toward them or driving away. It could be going slow; it could be going fast. To determine the range, course, and speed of the target, the officer of the deck needed to change the geometry and that meant turning. But with every course change came the possibility of losing the signal and not being able to reacquire it.
Nothing in their undersea game of cat and mouse happened without risk.
“Pull up a new query window,” the ACINT rider said, joining the ever-expanding huddle at Harris’s workstation. “This time, go ahead and put the decimal in—151.7 hertz.”
“Yeah, but it’s walking all over the place, 151.6 to 151.9,” Harris said, pointing at the trace on the upper monitor.
“I know, but the trend line is around 151.7. If you don’t put the decimal in, the database will give you all 151-hertz emitters. Also, add a location tag, Barents Sea. That will narrow the list.”
Harris did as the man said and pressed enter. This time only two results popped up: K-335 and K-391.
“K-391 is decommissioned,” the ACINT guy said. “Click on K-335.”
Harris clicked the listing and a new window opened with data.
NAME: K-335 Gepard
TYPE: Akula III–class submarine
PENNANT #: 895
STATUS: Active
FLEET: North / Arctic
PORT OF RECORD: Polyarnyy
PROPULSION: Single 7-bladed propeller
SOUND OFFENDERS: 151.7 Hz on port aft quadrant
“Bingo,” the ACINT dude said.
Harris deflated a bit at the news he hadn’t found K-329. “I was hoping it was the Belgorod.”
“No, this is a good thing. The Belgorod is in the final phase of sea trials. It probably has orders to conduct exercises with the Gepard. If we follow them, chances are good they could unwittingly lead us to the boat we’ve been tasked to find.”
“Agreed,” Chief Schonauer said. “Great work, Harris. Looks like you hooked your first shark.”
Harris felt his cheeks flush with pride at his chief’s shout-out and the possibility that his find could lead them straight to the Belgorod.
“Akula is the Russian word for ‘shark,’ ” the ACINT rider said. “In case you didn’t know that.”
Harris shot the guy a look. Of course he knew that, but he was too excited to get defensive.
I found my first Akula . . . how friggin’ cool is that?
“Officer of the deck,” Crystal said, turning toward the command station, where the OOD was standing. “We have a hit in the ADS on the narrowband contact. High confidence that Sierra Seven is the Gepard, hull number K-335—an Akula-class submarine homeported in Polyarnyy.”
“Good work, team,” the OOD said, addressing the group. “Time to turn and call the captain. Let’s see if we can get a good fire control solution on this guy and fall in trail.”