once. Basically, Jeffrey wanted to save the array for self-defense once they reached Texas; they'd had to ditch their other one at Diego Garcia, because it took too long to retract once there was an enemy torpedo in the water. But Kathy and Bell wanted to use the spare array now, or they might not be able to find the 212 and 214 at all. A search for broadband noise using the ship's hull arrays would also be problematic. Challenger was hiding in the deep scattering layer, a zone of dense biologics that caused false echoes for enemy sonar; at this time of day in this season and latitude, the layer was comparatively shallow, twelve hundred feet. The 212's and 214's crush depth was a bit deeper than that, so they might be cloaked in the layer, too — it tended to block sound over any substantial distance. Ilse suggested hunting for the U-boats by trying to look up at them from a greater depth — in sonar hole-inocean mode — using surface wind and wave noise to acoustically backlight the targets. The problem with that was they'd need to get very close to Master One and Two first, by sheer guesswork, before they'd have much chance of a contact. And even then, the Class 212 and 214 were tiny compared to Challenger — they'd be very hard to see as just two quiet spots against a noisy background.
Kathy stressed that any sonar search plan, in these conditions, would be at best an awkward compromise. Ilse looked like she wasn't sure what to think. She did point out that the seafloor here, at eighteen thousand feet, went way past Challenger's crush depth. Bell hinted, not so gently this time, that maybe they ought to just press on to Texas. The clock kept ticking. In his mind, Jeffrey decided. They'd follow the original line of bearing to the targets, course zero two five, and then assume the U-boats were slowly heading north to keep after the convoy fight while the 212 refueled. Challenger would use hole-in-ocean sonar: Kathy and Ilse had found two frequency bands where the biologic layer was relatively transparent to ambient noise.
For a moment Jeffrey felt self-doubt, or guilt or something. Had he picked this particular route for Challenger on purpose, to take him near the track of the convoy fight, for another chance to mix it up with the Axis while he held an independent command?
There were certainly quieter, safer ways to reach the Azores, and home from there…. Was he trying to leave a calling card for that ceramic-hulled asshole, Eberhard, using nuclear torpedoes to settle old scores from office politics?
'People, it's our job to be aggressive. We're going after the German subs.' The others nodded, seeming to Jeffrey relieved a decision was made, and glad they weren't the ones to have to make it. He told Ilse to use her knowledge of hydrodynamics, to try to model what the flow drag of the U-boats' fueling pipes might sound like. Jeffrey gave orders to arm the atomic warheads in torpedo tubes one and three, then flood the tubes and open the outer doors. The guys on Texas would have to hold on a little bit longer.
Jeffrey thought back to the courier envelope, unopened in his safe. What the hell did RECURVE ARBOR mean? Well, it would just have to wait. He certainly couldn't allow himself second thoughts now.
HALF AN HOUR LATER
'Anything yet?' Jeffrey asked.
'No, sir,' Kathy said.
Jeffrey went to talk to the navigator.
'It's been quiet out there for a while,' Ilse whispered to Kathy.
'The convoy battle has died down.'
'Think it's over?'
'No.' Kathy brought up a different display on her console. 'Still plenty of surviving merchant ships, see? The Germans must be lying doggo. Still a few surviving escorts, too. I can barely hear them pinging.'
'Doesn't that convoy have SSN escorts?' SSNs were nuclear-powered fast-attack subs.
'Apparently not,' Kathy said, 'or the frigates wouldn't use active sonar, for fear of showing the Axis subs where ours are lurking, by an accidental echo off their hull, you see. Most of our fast-attacks are needed to protect the surviving carriers anyway, or for independent operations like we're on now. There aren't enough SSNs to go around, Ilse…. Besides, if there were, they might be sunk by friendly fire. Surface and airborne antisubmarine forces tend to treat any submerged contact as hostile, and shoot before they ask questions…. So our fast-attacks stay clear.'
'I'm glad I'm not riding that convoy.'
'Those merchant mariners are the unsung heroes of this war, if you ask me. Just like in the last big brew-up, before our time.'
Ilse returned to her keyboard, refining ocean-model parameters to make better sense of all the raw data pouring in from the hull arrays.
Jeffrey came over and tapped Kathy on the shoulder. She turned.
'Any contact?'
'All five sonarmen are working on it, sir.'
'Anything, Sonar?'
'Not yet, Captain.'
'Have you run a systems check?'
'Several times, Captain.'
Jeffrey fidgeted at the Combat Systems consoles. The tactical nuclear Mark 88 deepcapable torpedoes in tubes one and three were armed and ready to fire. Lieutenant Bell had the conn.
'Helm,' Bell said. 'Time for the next search leg. Make your course zero four five.' Northeast. 'Slow to ahead one third, make turns for seven knots.' Going slower improved sonar sensitivity.
Meltzer repeated the orders verbatim for confirmation, worked the engine order dial and his control wheel, then called out when Challenger reached the altered course and speed. Jeffrey was pleased with the young man. Meltzer had ranked high in his class at the Naval Academy, and in the nuclear qualification training, and Basic Submarine Officers Course, but nothing beat the test of combat. Since leaving Diego Garcia, not so long ago, Meltzer had showed nerve and confidence. He was a tough kid from the Bronx, and Jeffrey liked him. He'd piloted the ASDS on the Durban raid, and done very well, and then done well handling Challenger herself in the running battle which followed. Jeffrey decided Meltzer would pilot the mini again, rescuing the men from Texas. Jeffrey smiled to himself. On his own junior officer tour, on a Los Angeles-class boat, a beginner enlisted rating had worked the helm, another the separate stern-plane controls, under the ever-watchful eyes of a diving officer. Back in those days SEALs rode freeflooding undersea scooters to the target, freezing their asses all the way — and a disabled sub had to wait for a deep-submergence rescue vehicle staged from the U.S. or Britain. Jeffrey was less pleased with Bell. Bell was third-generation Navy, true. His father and grandfather had been enlisted men: his father a chief in riverine warfare toward the end in Vietnam, his father's father a steward on a battleship in World War II. Bell had earned a place at Annapolis, and an officer's commission, and had a strong service record since then, but he kept second-guessing Jeffrey in front of the crew. He also seemed at times lately to lack confidence, or backbone, or something. Was he distracted, too distracted, because his wife was expecting? Would he really make the grade as acting XO? He ought to stick to that task, daunting enough for a mere lieutenant, and let Jeffrey make the big decisions as acting captain. It was a captain's job to make the tough decisions.
Jeffrey turned to Ilse and Kathy, not smiling at all now. 'So what have we got?'
'Still nothing,' Kathy said.
'The more time we spend doing this, the closer that two-twelve gets to being refueled.' Jeffrey pressed Kathy on purpose. The ship was going into battle, and Jeffrey had to take this new woman's measure fast.
Kathy nodded reluctantly. 'Recommend we go deeper, sir, for a wider look-up search cone, so as to cover a larger swath with each sweep we make.'
'Oceanographer, where's the axis of the deep sound channel here?' Sounds made near the axis tended to stay at the depth of the axis, a gambit to conceal Challenger from Master One and Two.
'Right around six thousand feet,' Ilse said.
'We'll continue our look-up from there.' Jeffrey. glanced at the clock yet again. 'We better spot them soon. Once they split up they'll make a smaller target, and be a lot harder to find.'
For a moment Jeffrey worried someone or something might be lurking for him in the deep sound channel, a kind of horizontal acoustic superconductor…. He thought of the men waiting and suffering on Texas, who were
