Sea of Shadows

radio circuit, Ensign Cooper keyed back into the USW control net aboard Towers. “TAO — USWE, the SAU Commander has upgraded our helo alert status to Ready-Five.”

The TAO’s voice came back immediately. “TAO, aye. Break. ASTAC — TAO, set Helo Ready-Five.”

The current Ready-Five helicopter, Samurai Seven-Nine was sitting on Antietam’s flight deck, spinning its rotors up for launch at that very second. It would be in the air in five minutes or less — time the screening ships would use to build a firing solution and refine their classification of the contact.

Cooper shifted his attention to the CDRT. Now came the tough part.

The next four or five minutes would be crucial. He needed to know what the submarine, designated Gremlin Zero One, was up to — before Antietam’s helo was in the air.

The first piece of the USW puzzle was in place; they knew the contact’s bearing. Instead of a tidy NTDS symbol, the contact appeared on the CDRT display as a red line extending from the center of the symbol for USS Towers to the edge of the screen. The angle of the line was 307 degrees: the bearing of the contact from Towers. The contact could be anywhere along that line of bearing, at a range of anything from a couple of hundred yards, to hundreds of thousands of yards. To localize him further, they would need to know his range. For an effective firing solution, they would also need to know the target’s course and speed, but that could be estimated with a good degree of accuracy once they knew the contact’s range.

Cooper keyed his mike. “UB — USWE, got anything yet?”

The Underwater Battery Fire Control Operator keyed up. “USWE — UB. That’s a negative, sir. The sonar track is looking pretty good, but it’s going to take me a while to nail this guy down off passive broadband alone. If you want something quick, I’m going to need a turn.”

“USWE, aye.”

If they’d had passive narrowband frequency data on the contact, the fire control computer could have calculated the target’s range based on minute changes in Doppler as the submarine moved through the water. Without frequency information, they were restricted to Target Motion Analysis.

While it would eventually give them the information they needed, TMA could take twenty minutes or more and would require them to turn at least once (and maybe twice) to feed the computer enough changes in bearing rate to do its magic. But turning wasn’t an option right now. He couldn’t afford to open up a hole in the formation. If he did, the submarine could slip through it and get inside the screen’s defenses — which was exactly what had happened to Kitty Hawk.

The ensign stared at the colored symbols on the CDRT. Every thirty seconds, another red line appeared, each one tagged by a tiny set of digits that represented the Zulu time of that particular bearing update. The red lines accumulated slowly. Using only bearings, this was going to take a long time. Too long.

He exhaled fiercely. “Shit.” He keyed his mike. “Sonar — USWE, have you got any kind of narrowband on this contact at all?”

“No discrete tonals, sir. The target is showing a tightly packed cluster of frequencies up around 550 hertz, but it’s so garbled I can’t do anything with it. Everything else I’ve got is too broad and diffused to track or classify. We are definitely not getting anything we can use for Doppler. Request permission to go active, sir.”

Cooper’s answer was immediate. “Negative, Sonar. Remain passive. If we spook this guy, he’ll pop off a shot at us and run like hell.”

Chief McPherson nodded. “Good call, sir. No sense in tipping our hand this early in the fight.”

Cooper tapped his fingers on the face of the CDRT. “Thanks, Chief.

What do you think about having Sonar adjust the depth of the towed array, to see if we can get some useful narrowband?”

Chief McPherson shook her head. “Never violate the second rule of USW, sir: ‘If you’ve got contact, don’t screw with anything.’”

“We’re running out of time, Chief. Antietam’s helo is going to be airborne in …” he checked his watch—“about two minutes.”

“It’s your call, sir,” the chief said. “Until we finish our watch turnover, you’re still the USWE. But if it were me, I’d say screw the helo. That’s a LAMPS III bird, strictly re-detect and attack. They’re not set up for search. They’ve got no business launching until we have the contact localized.”

A hand squeezed Ensign Cooper’s shoulder. He looked around to find the captain standing behind him. “Listen to your chief, Pat. I can’t count the number of times I’ve seen somebody lose contact because they were futzing with equipment line-up, trying to get a better picture.”

“What do I tell the SAU Commander when he starts screaming for amplifying contact data?”

“You let me worry about Captain Whiley,” Captain Bowie said. “You follow your search plan and keep your eyes open. And don’t get tunnel vision.”

“Sir?”

“There are four subs out there. Don’t let yourself get wrapped around the axle over one contact, especially if it’s POSS-SUB low. We still don’t have any real classification data on this guy. We don’t even know his range. He might still turn out to be an Omani fishing boat way the hell and gone outside of radar range, and his signal’s caught in the surface duct.”

“I’ve seen it happen, sir,” Chief McPherson said. “More than once. Just be ready to shift gears on a second’s notice if we get any new information on the contact.”

The ensign nodded. “I’ll remember that.” He looked up. “Are you ready to assume the watch?”

The captain said, “Hang on to it for a while, if you want to, Pat. This is your first no-shit bad guy, and he showed up on your watch. In my book, that means you get to chase him down. This will be your kill … if you want it.”

Ensign Cooper swallowed heavily. He was frankly surprised that the captain wasn’t pulling him off in favor of a more experienced USWE. He suspected that he’d been given the watch for the first leg of the search because the captain hadn’t anticipated any action so early in the hunt. But now the captain was trusting him with the safety of the ship — saying as much right in front of the CIC crew. True, the captain and Sonar Chief would be close at hand, in case he screwed up, but it was still a pretty clear vote of confidence from the old man. He felt a surge of nervous pride.

“I want it, Captain.” He turned to the chief. “This one is mine, Chief. You can have the next one.”

Chief McPherson took a step backward and crossed her arms. “Your show, boss.”

Ensign Cooper looked at the chief out of the corner of his eye. “Okay, I know the second rule of USW. What’s the first rule?”

The Sonar Chief smiled. “USW is hard. If you’re stupid, it’s impossible.”

The ensign raised an eyebrow. “You’re making this up as you go along.”

“No, sir, I am not.”

Cooper opened his mouth to speak, but he was interrupted by a burst of warbling tones from the Navy Red secure radio circuit, followed by a voice transmission. “SAU Commander, this is Benfold. Contact report to follow. Time, seventeen fifty-four Zulu. My unit holds passive broadband contact, bearing three- two-five. Initial classification: POSS-SUB, confidence level low. Believe this contact correlates to Towers’ Gremlin Zero One, over.”

Captain Whiley’s reply was as rapid as before. “Roger, Benfold.SAU Commander concurs. Designate your contact Gremlin Zero One, over.”

Ensign Cooper forgot whatever it was he’d been about to say. He was too busy punching keys on the CDRT. A bright blue line popped up, extending from the center of Benfold’s NTDS symbol to the edge of the screen. The blue line crossed the most recent bearing line from Towers.

His keyed-in commands instructed the computer to plot a hostile-submarine NTDS symbol (a red V-shape with a dot in the center) directly on top of the intersection of the blue line from Benfold and the red line from Towers. It was called a cross-fix. That’s where the submarine was.

“Gotcha, you little bastard.” He keyed his mike. “All Stations — USWE, we’re in business. Break, UB, stand by for range updates from the CDRT.”

“UB, aye.”