The carbon dioxide scrubber on Potemkin was back in operation and the air was fresh. Federov watched the sonar console.
Barracuda was not on the screen. Federov didn't know if she was sunk or whether signal interference in the deep sound channel prevented him from hearing her. He had heard neither implosions nor a train of debris settling toward the bottom.
"Engineering, how go the stern planes?"
"This is engineering. We can move them."
"All right. Prepare for maneuvering. Slow speed. Let's be quiet."
On Sorensen's screen the Alpha decreased speed and became quieter.
"Sonar to control, range now four thousand yards and holding. He's looking for us. Depth three eight zero zero feet."
"Control to sonar, activate target-seeking sonar." And pray he comes to his senses and backs off…
Sorensen looked at Fogarty, punched the button and a wave of high-pitched sound pulsed out of Barracuda's bow in a narrow sound ray aimed directly at Potemkin.
Popov screamed in pain, his eardrums ruptured by Barracuda's target-seeking sonar. Federov rushed to the sonar console. The pulse of sound that appeared as a bright streak on the screen was like a sharp jab in his guts. Their sonar had found him.
"All ahead full. Right full rudder."
For thirty seconds Potemkin's engines pushed her through a sharp turn. "All stop," commanded Federov. "Level the planes."
The American target-seeking sonar gave him an exact fix on Barracuda. Potemkin was gliding on her planes back toward the American's position. If a torpedo was coming right at him, he had a chance to evade by diving. The question rattling through his mind was whether or not the American torpedoes had an enhanced capability like their sonars. His choices were back off and run, or fight. If he ran, Dherzinski would never escape, the Potemkin would be fatally compromised by film and Barracuda would surface and report that Potemkin already had fired one torpedo. Which would bring out the whole damn United States Navy to hunt him down… He looked at Alexis, who had taken his position at the firing console. His friend was reading his mind, sharing his thoughts. He waited.
"Activate targeting sonar."
The waiting was over. "Targeting sonar activated. I'm getting one signal, Captain, from Barracuda. He hasn't fired."
Federov moved to the weapons station. This was his to do. "Alexis, take the helm."
"Yes, sir…"
Federov pushed the button. "Torpedo away."
He steered the torpedo toward Barracuda at forty knots, trailing its guidewire behind.
Barracuda's sonar screens blazed with red blips. "Sonar to control, he's fired a torpedo, wire-guided, speed forty knots. Torpedo range three seven zero zero yards and closing."
No more hesitation. No more options. The Russian had not backed off. "All stop. Prepare to fire Mark forty-five. Set detonation for maximum depth."
Hoek watched on his screen as the single red blip that was Potemkin began to blink. His hand trembled over the keys, then a spike of pain shot down his left arm. He could barely whisper, "Set detonation for maximum depth, aye."
"Fire one."
Hoek reached for the button, but his hand never made it. Clutching his chest, gasping for breath, he fell to the deck.
"Good God, I think he's had a heart attack," Springfield shouted, and ran toward the weapons console.
Springfield punched the buttons. "Chief, fire one."
Lopez muttered a prayer and pushed the button. The Mark forty-five leaped out of the tube and immediately nosed over for a fast run to maximum depth.
"Evasive maneuvers. All ahead flank. Left full rudder."
The warhead would explode in two minutes. By then Barracuda should be three miles away, and at that distance she should withstand the Shockwave that would pass through the water like a nuclear-powered tidal wave — except the Russian torpedo was still coming at them at forty knots.
Springfield looked at Hoek lying behind the weapons station. Luther bent over the weapons officer, pumping his chest. Barracuda was coming around a tight turn at speed and they were leaning into the deck. Torpedo alarms were sounding, but to Springfield it was almost as if they were echoes from another ship in another ocean on another planet. Suddenly the door to the sonar room opened and Sorensen stood there, looking around the control room, eyes blazing. The torpedo was gaining on them, he said.
Popov had fainted from the acute pain of his ruptured eardrums. Federov snatched away his earphones and pressed them to his ears. On the screen he saw Barracuda fire a torpedo, turn one hundred eighty degrees, then begin to accelerate away. Could Barracuda outrun his torpedo? For a brief moment he continued to guide the missile, but then heard the active sonar in the Mark forty-five — it was unlike any sonar he had ever heard. And then he knew. The American torpedo was diving, was already below two thousand feet.
"Evasive action," he ordered. "Left full rudder. Dive! Dive! Flank speed! It's nuclear!"
Potemkin turned and accelerated, and though the stern planes failed to respond quickly, the forward motion was enough to snap the torpedo's guide wire. The fish was now on its own, he no longer had control of it.
"The wire's cut," shouted Pisaro. "It's running wild." On the sonar screens the Russian torpedo went awry.
Barracuda's control room dared to hope.
Sorensen, standing in the control room door, turned back to Fogarty. His face said he was not ready to celebrate.
"Quiet on the boat," Springfield ordered. "Right full rudder. Engineering, give it all you've got."
The echo ranger in the Mark forty-five torpedo immediately recognized Potemkin, ignoring the frequencies of Barracuda and the Russian torpedo.
The two torpedoes sped past each other, missing a collision by fifty yards. The Mark forty-five closed on Potemkin.
Inside the Russian torpedo a relay snapped and the guidance switched to an active sonar homing system. The transducer heard and recognized the surge of sound from Barracuda's pumps, and the onboard computer smoothly turned the rudder to the left. The torpedo homed in on Barracuda's engine room compartment.
Sorensen heard the torpedo's high-pitched homing sonar as it bounced off Barracuda's hull. Barracuda's speed was now up to twenty knots, but the torpedo was rapidly closing the gap. Three minutes, four?… He stood up, took off his earphones and turned off the overhead speakers.
"I guess I'll be going to the beach. What say, kid, join me in a few rays?"
Fogarty was unable to speak. Found himself rising like a zombie to follow Sorensen. He felt nothing as he and Sorensen moved through the control room, barely heard Springfield order in a curiously bland voice, "Flank speed, stern planes down twenty degrees, sail planes down twenty degrees."
The planesman was staring at the sonar repeater, not able to accept what he saw. The helmsman wet his pants. Springfield stepped quickly across the control room to the helmsman's station, and pushed over the joystick himself.
The radiomen were trying to send up a communications buoy. Pisaro looked as though he had swallowed his tongue. Cakes was frozen in a hatchway, a tray of coffee in his hands. The tray slipped out of his grasp and crashed to the deck. He stayed immobile.
Sorensen and Fogarty proceeded aft.
In the maneuvering room there was silence. The nucs monitored their instruments with undistracted attention. After all, the system had never been pushed to the limit. A technician's dream come true.
In the engine room Sorensen peeled off his jumpsuit and entered Sorensen's Beach in his red Bermuda shorts. He snapped on the sunlamps and put on his sunglasses.
Fogarty came in. They pulled out the mat and sat there. Zapata crawled out of the shadows and looked at them.
The Mark forty-five reached its maximum depth six hundred feet above Potemkin. A spherical shell of high explosive ignited, imploding a perfect sphere of plutonium that instantly reached critical mass.
The warhead exploded.
In a millionth of a second a fireball thirty yards in diameter erupted into a mass of superheated steam. The sudden impulse of energy pushed out a shock wave that slammed into Potemkin with the force of a freight train. Her titanium hull was not designed to withstand that much asymmetric overpressure and ruptured in a dozen places. At four thousand feet the pressure of one hundred twenty-two atmospheres killed Potemkin in eight seconds.
Federov's last thought was of the hand of God grabbing his ship and crushing it in His fist.
The giant bubble of highly radioactive water vapor continued to expand, pushing above it a waterspout that rose one hundred feet into the air. The bubble rose swiftly to the surface, where it erupted over an area the size of a football field. A large wave radiated over the surface, and the steam was slowly diluted and dispersed in the atmosphere. When the waterspout fell back into the sea after a few seconds, all visible traces of a nuclear explosion vanished. All that remained was the sonic record heard by SOSUS and the sonar operators on Dherzinski twenty miles away.
Sorensen and Fogarty heard the explosion at the same time that the shock wave rolled through Barracuda.
Sorensen said only, "He didn't move after he shot his wad. He thought he was too deep to get hurt."
Fogarty sat perfectly still, his mind numbed, seeing only a picture of his toy submarine diving into Lake Minnetonka.
The Russian torpedo did not function perfectly. It struck Barracuda twenty feet forward of the reactor.
Exploding on impact, the warhead punched a hole six feet in diameter in the pressure hull, directly into the control room. The full, lethal force of the explosion struck Springfield, Pisaro, Hoek, Cakes and the others in the control room. Cracks radiating from the rupture opened around the circumference of the hull.
Barracuda broke in half.
The blast expended itself against the, forward bulkhead, which caved into the officers' quarters and galley. The aft bulkhead resisted the blast, and the stern broke away and began to sink.
Eight thousandths of a second after the explosion ripped Barracuda in two, the sea and the laws of physics finished her.
In the bow, only the new steel installed at Rota failed to shatter in the succession of implosions. Lopez, the torpedo gang and the damage-control team of Davic and Willie Joe died in the last implosion.
In the stern, water poured into the reactor compartment, instantly cooling the reactor vessel, which became brittle and split open. The primary coolant water, saturated with radioactive isotopes and pressurized to sixteen hundred pounds per square inch, exploded into the flooding compartment and became mingled with the sea.
Water poured into the engineering spaces, squeezing the atmosphere in the compartment into a smaller and smaller pocket until the air itself exploded, destroying the turbines and reduction gears.
An electrical fire ignited a tank of light lubrication oil that exploded and destroyed Sorensen's Beach. Fogarty burned up.
As Barracuda sank to the bottom, twelve thousand feet below, Sorensen lived long enough to drown.