Deep Sound Channel (01)

by Joe Buff

  Jeffrey suspected the mines within the safetycorridor-of-the-day were switched off by acoustic remote control, to protect Axis submarines from faulty fuzing. If so, they'd be reactivated later, when the safety corridor changed—too bad there was no survivable way to check out Jeffrey's theory.

  Jeffrey saw that the lane plotted on the nav chart took a bend to port.

  "Helm," Wilson said, "left standard rudder. Make your course one four three."

  "Left standard rudder, aye," Meltzer said. "Make my course one four three, aye."

  Wilson turned to Jeffrey. "It's clever how they arrange it, XO. Inbound traffic comes down from the north, drifting with the current. Outbound vessels sneak off south, also using the flow"

  "That's just what I'd do, Captain," Jeffrey said. "It lets the diesels save their batteries and helps their SSNs to make less noise. With the tighter vertical contours down the coast, it gives 'em a free ride out to the thousand-fathom curve."

  "Take a look at this, XO," Wilson said. "Radio room just decoded it."

  Jeffrey took the message slip. The news was four days old.

  SAS VOORTREKKER SIGHTED 67 SOUTH 09 EAST X DAMAGED BY Q-SHIP

  THEN SUNK BY MULTIPLE NUCLEAR DEPTH BOMBS X PASS GOOD NEWS

  TO ALL YOUR PEOPLE X VOOR IDENT AS SSN HIT USS RANGER X MAY

  RANGERS CREW NOW RIP AVENGED X CNO SENDS XX

  "Well, that's a relief, sir," Jeffrey said. "Maybe the tide's starting to turn our way now"

  He went back to his screens.

  Jeffrey noted that the exact layout of the safety route got vague ahead, as Challenger drew ever farther from the hummock where she'd waited for the minisub and deployed the probes. This was because the distance covered since retrieving the ASDS was starting to rival the effective range of the LMRS autonomous-mode acoustic links, especially in these noisy current-strewn and halocline-ridden waters.

  "Sir," Jeffrey said, "recommend we deploy an LMRS again on a wire. We can send it on in front to scout our track while we keep moving. Have it scan the bottom for us, and use it to help triangulate the enemy patrol craft and helos. We ought to be clear of the coastal defenses before its battery runs down."

  "I concur," Wilson said. "We'll get much better clues on where the safety corridor is or isn't. Chief of the Watch, deploy an LMRS with a fiber-optic wire. Make its course one four three true, run it out to five thousand yards ahead of Challenger. Then maintain that range to own ship and maintain the zero zero zero relative bearing when you can."

  "Aye aye, sir," COB replied.

  Jeffrey used a window on one of his screens to study the data from the probe. Visibility was poor, the water turbidity high from bottom muck still settling after the A-bomb shock and the heavy silting by rainstorm runoff all along the KwaZulu/Natal coast.

  "COB," Jeffrey said, "get a close-up of that mine." Jeffrey looked at the UHF mine classification sonar image. "Captain," Jeffrey said, "this is interesting. This one's a regular bottom influence device, not a CAPTOR. Must be the Boers are worried a torpedo cutting loose so close to base might run erratic and home on the wrong side's vessel."

  "You're probably right, XO."

  Jeffrey told COB to check a few more mines along their course. None of them were CAPTORs either.

  "Sir," Jeffrey said, "we're coming to another bend in the corridor. It turns to starboard here, to avoid the old ammunition dumping ground, and at this point it must lead right into the bluff. Recommend we push the LMRS further away from us, to explore the outbound safety track in detail. This near to Durban I suspect the whole area's forbidden to ASW."

  "That's risky, Fire Control."

  "Captain, it'll give us a clearer view of what lies ahead, increase our options in case we have an equipment casualty or something. It'll also widen our base line for triangulation, since we lost our thin-line towed array and the older fat line's less useful in the littorals."

  "Very well, XO. I concur." Wilson gave COB the orders, then had Meltzer turn the boat to starboard on course two four zero.

  "Captain," Jeffrey said a little later, "I'm wondering if while we're here we shouldn't drop some mines of our own. Who knows what we might sink."

  "XO," Wilson said, "that is too risky. We'd make mechanical transients loading and sending them out, plus their own propulsion noise might be picked up, and launching them creates dead-certain proof that we were here."

  "Understood, Captain," Jeffrey said. He almost blushed. The exhilaration of sneaking in this close to the heart of darkness was making him impetuous. I better cut that out, he told himself.

  Commodore Morse came into the CACC. "I spent some time with the SEALs," Morse said. "Sounds like you all did a terrific job."

  "Thank you, sir," Jeffrey said.

  "You too, Ilse," Morse said.

  Ilse turned and smiled. "Think there'll be women commandos someday, Commodore?"

  "Maybe there are now," Morse said, "and they aren't telling." He winked.

  Morse turned back to Jeffrey. "If I were you, I'd help Clayton write up the SEAL chief for a Medal of Honor. As a lieutenant commander and not part of his unit, your word as witness would add a lot of clout."

  "That's a great idea," Jeffrey said.

  "If I may," Morse said, "let me offer another suggestion."

  Jeffrey noticed Captain Wilson didn't mind the input—the two senior men had gotten close since leaving Diego Garcia. "Go ahead, sir," Jeffrey said.

  "One thing we learned in the Falklands," Morse said, "from all our surface ship losses, is the absolutely crucial importance of aggressive damage control. The SEALs are busy cleaning their gear and drafting their after-action reports, but that's mostly make-work."

  "That's sort of true, sir," Jeffrey said. "It doesn't take that long to clean a rifle and rinse a regulator valve."

  Morse nodded. "I think you ought to add them to your repair party roster. Good upper-body strength, terrific endurance, mental calm under pressure, and let's say they're very used to working in the face of death hip-deep or more in freezing seawater with salt spray in their eyes."

  Jeffrey turned to Wilson. "Captain?"

  "XO, manning questions are your call."

  "I agree, then," Jeffrey said. "Thanks, Commodore. . . . Messenger of the Watch, once we secure from full ultraquiet, report to the engineer. Ask him to assign Clayton and his people to a damage control party somewhere forward."

  "Assign the SEALs to damage control, aye, sir," the messenger said. He jotted in his notebook.

  Jeffrey got up to stretch. His left leg was starting to ache terribly.

  "Problem, XO?" Wilson said.

  "Just my old wound, Captain. Overexertion, probably, or delayed reaction to the stress."

  "How you feeling otherwise?"

  "Tip-top, sir," Jeffrey said. Surprisingly that was true—the miracle of adrenaline.

  "Phone Talker," Wilson said, "call the corpsman to the CACC."

  "Sir, that's really not necessary," Jeffrey said.

  "XO, here on Hans's doorstep I need you at a hundred ten percent. Let the corpsman give you an aspirin."

  As Jeffrey walked around, his leg suddenly buckled. Morse caught him and helped him to sit down. The corpsman came. He started checking Jeffrey very carefully, testing his reflexes and listening to his chest.

  "Will I live, Chief ?" Jeffrey said.

  "Sir," the corpsman said, "you may be having decompression sickness."

  "That's ridiculous," Jeffrey said. "We followed procedure exactly."

  "Commander, you know as well as I do decompression's a stochastic process. There're always people who show random hits not predicted by the data. The problem you've got is all the scarring in that leg. It doesn't fit well with any of the tissue compartment models that crank out the navy diving tables."

  "So now what?" Jeffrey said. He reminded himself that two deep dives in a short period was especially risky.

  "I'm giving you this painkiller. I'll check with you in half an hour. If the leg still hurt
s, you go into your rack and go on oxygen. Any twitching or slurred speech, dizziness or discoordination, you go into the hyperbaric chamber."

  "Just what I need right now," Jeffrey said, swallowing the pill. He washed it down with coffee.

  The corpsman looked Jeffrey in the eye. "Don't take chances with your health, Commander." He left the CACC.

  Jeffrey went back to studying the LMRS downlinks. All of a sudden the bioluminescent glow flared up, much brighter than its background level. Then a big shadow seemed to cross the field of view.

  "What the hell was that?" Jeffrey said. "COB, catch up to it, bring the LMRS closer."

  "Bring the LMRS closer, aye." COB worked his joy stick. "I'm getting buffeting," he said. "The contact's not just drifting, there's wake turbulence."

  "Sonar," Jeffrey said, "what's ambient Doppler show? Vortices from fins and flukes?

  Ilse, can you help?"

  "Look at this," Ilse said. She relayed Jeffrey a false-color picture of the turbulence. It had a circular cross section.

  "Pancake eddies," Jeffrey said. "Enemy sub! Designate the contact Master 26! TMA team start a plot!" "She must be leaving on patrol," Wilson said.

  "More likely a quick sortie to get her arse away from

  the next incoming A-bomb," Morse said.

  "It's a diesel boat on batteries," Sessions said. "It's too quiet to be nuclear."

  "COB," Jeffrey said, "don't lose it. Put the LMRS in trail, right in her baffles!" Jeffrey grinned, forgetting the pain in his leg. "Captain, we can follow Master 26 right out to sea.

  "

  ABOARD VOORTREKKER, LEAVING

  THE BLUFF SUBMERGED

  The air in the control room still smelled very foul, even after three days of round-the-clock repair work and a jury-rigged new forward fan room installation.

  "Synchrolift rolled out against the detents," Van Gelder said. "Outer subsurface blast doors closed behind us. Captain, we're ready to blow negative and get under way."

  "Very well," Jan ter Horst said. "Bring us up ten meters smartly."

  Van Gelder passed the orders, in his role as diving officer when leaving port. He watched Voortrekker's depth decrease and hold. The pressure gauge declined by one bar exactly. The Agulhas Current caught the ship at once.

  "Slow ahead," ter Horst said, "make revs for seven knots."

  Again Van Gelder passed the orders and the helmsman acknowledged.

  "That's fast enough to not waste any time," ter Horst said, "in case the Allies try to hit the bluff again. Not that ground-penetrator gun bombs would get through all the layered armor under the hostage camps, but we better hope the next one doesn't go off underwater."

  "It seems less and less likely there'll be another blast, Captain," Van Gelder said.

  Ter Horst harrumphed sarcastically. "Either that or they know they missed and they want to get us lulled before the next one! Seven knots lets us stay quiet and at this depth avoids a surface wake—no need to draw attention to ourselves. It also gives that Daphne-class pig boat a chance to draw ahead."

  "Er, I concur, sir," Van Gelder said, abashed.

  "Port ten degrees rudder," ter Horst said, "steer two zero five."

  "Aye aye," Van Gelder said. "Steering two zero five, Captain."

  "Very well," ter Horst said. "Stand by for the Umlazi halocline."

  ABOARD CHALLENGER

  "Helm," Wilson said, "left standard rudder, make your course two zero five."

  "Left standard rudder, make my course two zero five, aye," Meltzer said. In a few moments Jeffrey heard, "Steering two zero five, sir."

  "Very well, Helm," Wilson said.

  "Commander," Ilse said, "we should be coming to another halocline. Salt content will decrease about two parts per thousand seawater."

  "Very well, Oceanographer," Jeffrey said. "Helm, can you compensate for decreased buoyancy with up-angle on the sternplane functions?"

  "Not the way she's been handling, sir," Meltzer said, "not at this speed without the bowplanes. We'll have to run the low-rpm variable ballast pumps."

  "Very well," Jeffrey said. "COB, at your discretion."

  "Adjusting buoyancy with quiet centrifugal variable ballast pumps, aye," COB said. "

  Ilse, you can't imagine how much it helps to know a halocline's coming. Sometimes when we hit one, it's like being in an elevator and the cable broke."

  "It's quieter this way too," Jeffrey said. "We can do the pumping gradually."

  "You're welcome," Ilse said.

  Jeffrey watched Challenger's depth decrease and her nose come up slightly. Then she dropped back down to proper depth and trim as she entered the less salty water bow-first.

  "You're an artist, COB," Jeffrey said.

  "This boat's a work of art," COB said.

  At $3.7 billion, the most expensive SSN in history, she better be, Jeffrey told himself.

  Challenger's construction drew on quality control standards so demanding Admiral Rickover himself would've been jealous. Defense analysts in the know had called the new ceramic fast-attack boats an RMA, a revolution in military affairs, one of the most important advances in undersea warfare since the advent of nuclear propulsion and deterrent strategic missile subs. Jeffrey knew the pressure was on to prove his vessel's worth, or there might never be another in the U.S. Navy, even if the good guys won this war.

  "Captain," Jeffrey said a minute later, "something's been preying on my mind."

  "What's that, Fire Control?"

  "The ISLMMs, sir, the improved sub-launched mobile mines," Jeffrey said. "With respect, I want to recommend again that we deploy a few."

  "X0, I agree with you completely that it'd be great to sink some Axis shipping, since we'

  ve paid the price of admission to the bastion. But our top priority must be an undetected egress."

  "But that's the point, sir," Jeffrey said. "If you think about the mission overall, it's not specifically an undetected egress that we want. What's required is the enemy not draw some connection between our presence and the Umhlanga Rocks event."

  "Go on," Wilson said. Looking around, Jeffrey realized he had Commodore Morse's full attention too.

  "It's a gamble to assume we'll get away without being detected," Jeffrey said.

  "Granted," Wilson said.

  "Submarining's a business of calculated gambles," Morse broke in. "If you don't feel your gut twisting, you're probably not doing your job."

  "Then consider this calculation," Jeffrey said. "We're using a safety lane to escape. We might be spotted doing it. We may have been spotted already, for all we know. We have no way to tell since they'd ignore us. But, records of the detection would be made, even if unwittingly, in submarine deck logs and surface-unit Combat Information Center data, and sonar tapes and so on."

  "Concur with that part," Wilson said.

  "That means the opposition could eventually reconstruct that there was an extra submarine, us—that we were present and we weren't one of theirs."

  "Oh dear," Morse said. "I think I see where you're going with this."

  "The point is," Jeffrey said, "if we plant some mines, we're offering the Boers a red herring, an excuse or reason for us to have come by. That way when they investigate the nuclear explosion, their paranoia can still run wild. The board of inquiry can find it credible that we were in the area by coincidence, and then they start the purge we're hoping for."

  Wilson actually smiled. "Very finely reasoned, Mr. Fuller. You're saying it's actually the lesser of two risks to launch some mines, in the bigger picture."

  "Exactly, Captain. The fact we did plant mines suggests we weren't trying to hide completely, we weren't responsible for Umhlanga Rocks."

  "You're not afraid that we'll make noise and draw too much attention just a little too soon?" Wilson said.

  "Sir, the LMRSs haven't found a single SOSUS hydrophone this close inshore, and ones looking back at us from deeper water will be impaired by lots of reverb off the bottom's upslope. It'd take them ho
urs of computer time to eke out and confirm our signature."

  "That's true," Morse said. "It makes us tactically invisible."

  "Yes, sir," Jeffrey said, glancing at his displays again. "If Master 7 and Master 23 here don't change course, in a couple of minutes we'll have a good window to launch from outside their detection envelopes."

  "Very well, Fire Control," Wilson said. "Prepare to launch two ISLMMs. Make the runs be short, place the warheads at your discretion."

  "Prepare to launch two ISLMMs, aye," Jeffrey said.

  "Before we do I want to check our baffles," Wilson said. "Master 26 still holding course?"

  Jeffrey eyed his screens once more, then double-checked with COB, still piloting the LMRS in the diesel's wake. Jeffrey turned back to the captain. "Affirmative, sir, the contact's dead ahead, steering two zero five on batteries, range from us eleven thousand yards, no towed array. Sir, we're getting two side-byside opposing swirls in the turbulence. I think Master 26 has twin screws."

  "That would make her a Daphne class," Morse said. "They're forty years old. . . Or maybe one of the Russian Tangos they bought used. Foxtrots have three shafts."

  "Very well," Wilson said. "Our side's forced to use some reconditioned obsolescent hardware too. . . . Helm, on my mark all stop, then right full rudder and turn sixty degrees to starboard, then use auxiliary propulsors to cancel our remaining way. We'll drift with the current and listen with the wide-aperture arrays, while Fire Control prepares to launch the mines."

  "Understood," Meltzer said.

  "Mark," Wilson said.

  "All stop, right full rudder, aye," Meltzer said. "Maneuvering acknowledges all stop. . . .

  Steering two six five, Captain. . . . We're holding inside the corridor, sir."

  "Very well, Helm," Wilson said.

  Jeffrey went to work. Deciding exactly where to put the total of four conventional bottom influence warheads was a nontrivial exercise, especially on short notice. Of course part of his mind had been planning for it all along. He'd lay a line across the current, not parallel to it, so one sinking vessel wouldn't drift downstream and set them all off each in turn. He decided a spacing of two hundred yards would be tight but not too close, spread across the safety lane. If no good targets used this particular lane today, eventually they would.