Piranha: Firing Point

“Part one — diesel boat search. We’re looking for a diesel on the battery, looking for low-frequency main-motor or screw noise. Not much chance of finding her, so processing time would normally be low since we don’t want to waste time, but on the other hand, ‘Diesel Boat Eddy’ is more likely to be found out here than the other threats, so we’ve upped the processor time.

“Part two — snorkeling diesel boat search. We’re trying to find a low-and medium-frequency ocean noise from a diesel engine, like we’d hear from a diesel boat snorkeling at periscope depth, recharging the batteries. Not much probability on this one, because anyone trying to attack the fleet would sure as hell want to keep it quiet.

“Part three — nuke boat. We’ve got it tuned for three nuke profiles. The first an older 688 boat, like the kind we sold to the third world. Low probability on those.

Second profile is an updated Han-class, like the Reds used to have, but which should have rusted to dust twenty years ago. Who knows? Maybe someone kept an old vintage boat and sent it to sea. Also low probability.

And damned loud if it is out there — I’d hear it with my naked ear. Third profile is a French Rubis-class, the sub they sold on the market for ten years. It’s tiny, it’s loud, and it has only eighteen weapons. This is also low probability.

“Part four — all sub classes. This is the transient classification system. We’re looking for any of about four hundred transient noises, all of which are guaranteed to be manmade. Hatch slams, pump startups, check-valve slams, dropped wrenches—”

“Torpedo tube doors coming open,” Patton added.

“Oh, yeah. Torpedo gyro startups, torpedo propulsor startups, and a bunch more. None of which can come from whales or shrimp. The processor module is brand-new, and we’re not sure how well it’s going to work.

You’d better prepare yourself for some false alarms. We could hear a hatch slam and it might just be a whale fart.”

“And that’s it?”

“That’s it. Skipper.”

“What about that alert that came from USUBCOM, the one about possible variants of Japanese Destiny or Rising Sun ships being used by the Red Chinese?” Patton had read the skeletal message from Admiral Pacino, with veiled references to the Reds possibly having some Japanese-type submarines, but it had sounded strange.

“USUBCOM thinks the Reds stole the technology, reverse-engineered a nuke platform based on the Destiny or the Rising Sun. Yeah, I saw it Trouble is, a reverse-engineered carbon copy of a Destiny won’t sound like a Destiny. The sound signature would be nothing like the copied boat”

“So, why would USUBCOM put us on alert for a Destiny or Rising Sun?”

“Especially when our intelligence would come up with any carbon copy the Reds had been building or testing out in Go Hai Bay? You got me. Skipper. I’m lost”

“Doesn’t add up. But what if they somehow got the Japanese to do something for them? Japanese could still be upset with us after the blockade….”

“Come on. Captain. That makes zero sense. They put the Rising Suns to sea with American permission.”

“Yeah, and then they all sank.”

“Who knows? Maybe the USUBCOM engineering guys sabotaged the Rising Suns. Maybe the Japanese subs were considered too much of a threat” Demeers said, his active imagination firing up. Patton glanced at the dogeared science fiction novel on the side console, Demeers’ passion. He wondered if the sonarman’s reading preference was affecting his on-watch thinking.

“I highly doubt it And it just seems like it’s off the wall. Destinys? Rising Suns? What next a Severodvinsk-class Russian?”

“No more whacky than a Rubis or a Han or an old Los Angeles.”

“True. What if we put some processing time on a Rising Sun?”

“I’d be happy to. Skipper. Just one problem. We don’t know what the hell they sound like.”

The old search paradox had returned, Patton thought.

They couldn’t very well search for a sub unless they knew its “sound signature,” the pure tones that it emitted from its rotating machinery. It was usually discovered only by shadowing a new submarine, lead ship of the class, with a U.S. sub, recording the sounds heard as it submerged the first time out of the shipyard. But absent that acoustic intelligence, it would be difficult at best to find an intruder submarine. Perhaps only the transient noises would give it away.

“So, here we are, steaming ahead of the convoy, going max out at forty-one knots, half deaf because of our own speed, half blind because we have no idea what we’re searching for, with cryptic messages that there might be an advanced-technology Japanese sub or mirror image out here, and we’re supposed to keep the whole East China Sea clean with all that?”

“That’s it. Skipper. That’s why you get that command pay.” “Yeah, all forty bucks a week,” Patton said. “You got an old Destiny III search plan?”

“Sure. It’s covered with dust, but yeah, I could find it for you.”

“Do me a favor. Load it in. It’s as realistic as a Rubis or a Han.”