Voyage of the Devilfish mp-1

by Michael Dimercurio

  “COMMUNICATIONS EMERGENCY. COMMUNICATIONS EMERGENCY. NAVIGATOR, COMMUNICATOR AND RADIO CHIEF REPORT TO RADIO IMMEDIATELY.”

  “Six five feet, sir,” the Diving Officer called. The ship had levelled off. It took what seemed like an hour for the periscope to come out of the well. Toth focused on the bearing to the AKULA’s launch position, and his heart sank. The bright white rocket exhaust traced a graceful arc up to several thousand feet, a beautiful fourth of July rocket, except that as Toth watched, the fire trail suddenly stopped. There were no fireworks. No more fire from the tail of the rocket. Only a smoky parabola etched in the night sky. Which meant the first stage, the solid-rocket motor, had been exhausted and the jet-engine sustainer had kicked in, sending the rocket on its way. It was no longer visible, not just because of the jettisoning of the rocket motor but because it was cruising below the radar grass, maybe only forty feet above the water.

  But the worst part was the direction of the liftoff. Toth had hoped the missile might have been knocked off course by the Mark 49 torpedo detonations’ shock-wave. No such luck. The rocket motor exhaust pointed due west, in a perfect trajectory toward Norfolk.

  Toth handed the scope over to Culverson. “You have the Conn. Secure battle stations. I’ll be in radio.”

  The emergency nuclear-warning message was called an OPREP 3 PINNACLE for some forgotten reason. Just a code word for a flash transmission to the White House consisting mostly of numerals in preformatted fields. The mere fact that it was being sent would be drama enough at COMSUBLANT and CINCLANTFLEET Headquarters.

  At 0917 Greenwich Mean Time the BIGMOUTH antenna of the USS Billfish came out of the sail and transmitted the remarkable, harrowing message. The communication went out first on the NESTOR UHF satellite secure voice circuit, then on a teletype burst communication coded to the satellite, also by UHF. The messages sent, there was no sense lingering at periscope depth. Yet Toth wanted to stay at the surface to see if the transmissions on the HF frequency from COMSUBLANT HQ stopped suddenly, which would indicate their incineration. He especially wanted to see if the CINCLANTFLEET SIOP WARPLAN implementation message would come through at FLASH priority. The SIOP WARPLAN was the collection of detailed instructions on exactly how they were to proceed in the event of a battle. Toth walked slowly forward to the control room. All eyes of the watch standers were staring on him. He cleared his voice.

  “Off sa’deck, lake her deep to 546 feet. Ten knots. Start searching for another Russian attack unit. Maintain the rig for ultraquiet. And stream the buoyant wire antenna. I want to be in synch on VLF in case anything is transmitted from ashore.” He stood at the red sonar monitor panel of the Conn, waiting to find another Russian submarine, waiting for radio instructions to reach him from his wire antenna skimming the surface 500 feet above — or much worse, for no instructions to come from an incinerated headquarters. It was time to give one more order.

  “Off sa’deck, tell the Communications Officer to get into his top secret safe. Have him bring the CINCLANTFLEET SIOP WARPLAN to the Conn.”

  CHAPTER 18

  19 DECEMBER, 0924, GREENWICH MEAN TIME

  ARCTIC OCEAN

  BENEATH THE POLAR ICECAP

  USS DEVILFISH

  “Captain, the fire-control system is overheating, we’ll have to shut it down.” Weapons Officer Lieutenant Commander Steve Bahnhoff looked very unhappy. Pacino gestured for Bahnhoff to wait. He had a last chore in mind for the Mark I fire-control system.

  “Two minutes since the Magnum launch, Captain,” Rapier said, urging Pacino to return fire.

  “Very well, XO.”

  What had his father thought over two decades before when an older Russian torpedo was on its way, just as a bright shiny Russian Magnum was now on the way to the Devilfish? Had Patch even had time to think? An image of his father coughing up blood and seawater, drowning in both, came to him, etched in his mind. It was almost time. Time for payback. Pacino literally felt the eyes of his crew on him, waiting for his lead. The quiet was palpable. No bass rumble of ventilation. No whine of the SINS navigation system. Only half the lights, the sonar and fire-control systems were functional. Without air-conditioning the residual heat from the steam and reactor plants made the ship stuffy and hot.

  Bahnhoffs voice broke the silence. “Captain, fire-control casualty… it’s a disk crash. fire-control is in tape mode.” Which, of course, meant the system would be twenty times slower and all positions would show the same clunky tape-mode display, the line-of-sight view. Pacino had no time to answer.

  CHICK! CHICK! PWEEP! CHICK! CHICK! PWEEP! …

  “Conn, Sonar, Magnum torpedo is doing a range check.” Pacino didn’t answer. Bahnhoff looked up at him. “fire-control temperature is almost a hundred and fifty, sir. We’re about to lose it…” But Pacino had to wait. The Magnum was still on its way in. Would the fire-control system hold out till the torpedo passed? More to the point, would the Devilfish herself survive?

  * * *

  The Magnum torpedo, serial number 0011779, propelled itself through the cold arctic sea with an external combustion engine, combining fuel with liquid oxidizer in a combustion chamber and sending the expanding gases to twin Bend hydraulic motors, spinning the concentric propulsor shafts. The engine design was old but ingenious. The torpedo cruised through the water, its counter-rotating screws just on the verge of cavitation, its slippery surface enabling it to get up to its final intercept velocity of 110 kilometers per hour. One hundred ten clicks. Fastest torpedo on earth. At the moment, however, the weapon meandered beneath the ice at a leisurely 70 clicks, making sonar reception better. There would be time to speed up to intercept speed once the weapon identified where the enemy ship was.

  At first the Magnum “listened” passively as it cruised out toward the target position that the Kaliningrad’s computers had described to it before launch. It had a great deal of memory devoted to the sounds of the American nuclear submarines. Tapes of every submarine class had first been analyzed and coded into the digital memory. Later, tapes of every hull of the American fleet had been inserted. This target’s hull-number, SSN-666, had been fed in only minutes before, but the data from its August sound surveillance, stolen by an industrial espionage agent from the Dynacorp International Sound Analysis Division, indicated that the 666 had a slight amidships rattle when it ran slow-speed reactor recirculation pumps. Its fast speed pumps were so noisy that no comparison data was needed. After a few moments the weapon had “heard” nothing and switched to active sonar. The torpedo cruised on! “knowing” that the 666 was immediately ahead, and waiting for its noise to manifest itself in the listening-sonar gear.

  USS DEVILFISH

  “XO, set the Hullcrusher in tube one to passive-sonar mode with a circling pattern, orbit point 10,000 yards away down the bearing line to the OMEGA. Tubes two, three and four, the same. Tube-two unit at 15,000 yards, tube three at 20,000 and four at 25,000. All will need to transit at high speed to the orbit points.” Pacino’s voice was level but his thoughts of his father moments before had brought a sickening taste to his mouth.

  “Sir,” Rapier asked, “you sure you don’t want active sonar mode with the snake pattern? The active mode will still screen out the ice noise. It’s a doppler sonar. And the snake pattern will cover a hell of a lot more territory—”

  “No.” Pacino cut him off, wondering how Rapier could argue, with the pinging of the Magnum coming in louder every second. Pacino looked down at the fire-control display. The snake search pattern was a superb open-ocean torpedo program that made the torpedo wiggle side-to-side and up-and-down as it searched, covering huge ocean sectors with the sonar gear either passive or active. But for an underice shot Pacino had decided on a passive circler, a Mark 50 torpedo shot out to a preset range, then instructed to swim in circles until a target came into its passive-search sector. Without some kind of solution, active or passive snake shots would just dud. They examined too thin a slice of the ocean. At least a circler would look around a
ll 360 degrees. And active sonar was out — it would alert the OMEGA that something was there. There was even the possibility a torpedo would home in on another friendly torpedo. It might work, but the odds were still against the OMEGA blindly driving into one of the torpedo’s search cones. Still, it was all Pacino had.

  “With four active snake torpedoes out there,” Pacino said to Rapier, “the whole icepack would be filled with pinging. Our solution is getting stale without maneuvers and ownship speed. The OMEGA could be anywhere on this bearing line. Passive circlers are our only chance. All right, XO, program the weapons.”

  Rapier nodded. “Programming now.”

  The Magnum’s sonar pinging still sliced through the hull, getting clearer and louder. How long would it continue inbound, Pacino wondered.

  “We can’t launch until this torpedo goes by, if it goes by, but if we fool it I intend to shoot everything in the torpedo room at Target One.” Rapier took it in.

  “Conn, Sonar,” Pacino’s earpiece rattled, “loss of Target One. Signal-to-noise ratio went below threshold.” Pacino and Rapier looked at each other for a long moment. The Russian had disappeared. The torpedoes would be duds for sure now. Pacino pressed on, seeming to ignore the bad news. “And XO,” he said, having to speak over the noise of the incoming Magnum torpedo’s screw, “all units will have ASH disabled.”

  “Sir, with Anti-Self-Homing disabled, the units could swim back and acquire on us.”

  “I know, but you heard sonar. We don’t even know a bearing to Target One now. He could be anywhere. Time for an educated guess.” Both men paused to listen to the whine of the incoming nuclear-tipped torpedo.

  The plot and fire-control officers were staring at the two men. Then, as the torpedo’s sonar sounded through the hull, all eyes looked sideways to port, as if they could see through the steel to the approaching torpedo outside. The ping-pitch had dropped from a shrill squeak to medium tone, the screw noise had gotten deeper, the noise no longer coming from the port side but fading away to starboard.

  Pacino looked at Rapier. “We fooled it.”

  “Kicked its ass,” Rapier said, the stress leaving his face for a moment.

  “Conn, Sonar,” Pacino’s earpiece announced, “we’re getting down doppler on the torpedo. It’s past CPA and opening.”

  “Sonar, Captain,” Pacino said into his microphone, “any reacquisition on Target One?”

  “Conn, Sonar, no…”

  Pacino’s relief quickly faded. “Attention in the fire-control team,” he called out to the room. “We’ve gained a little time but the Magnum may come back around when it realizes it’s been had. I’m going to try to get some weapons out before the Mark I system shuts down on high temperature. And since we no longer have sonar contact on Target One we will be firing on our best guess. Carry on.” Pacino paused, eyeballing his officers, adrenaline pumping, sweat pouring… an intense mix of feelings almost sexual.

  “Firing-point procedures,” he said, voice low and tight.

  “Tube one. Target One, passive circler, ten thousand yards…”

  * * *

  The Kaliningrad had had no accurate range at the time of launch so the Magnum swam out the bearing line toward the aimpoint — the point that the target, hull number 666, was expected to be at expected detonation time, ten minutes after launch. The Magnum was using its active sonar to ping and “listen,” attempting to pick up the enemy. Its program codes had been modified by the underice subroutine. Normally the sonar would ping and pay attention to any solid return ping, but since this action was happening under the icecap, the ice rafts and pressure ridges and stalactites would return a ping as well as an enemy submarine. The subroutine instructed the Magnum to use the doppler filter, the device that rejected stationary objects and only examined moving ones. When a ping went out from the torpedo, return pings at the same frequency were disregarded. Only pings with an upshift or downshift in frequency passed through the filter since a moving object physically changed sound waves. If it moved toward the listening ear, the object’s speed compressed the sound waves — and the frequency went up. Motion away rarefacted the waves, shifting their frequency down. Like a moving train’s whistle would be shrill and high-pitched when the train approached, low-pitched and fading when the train went away. So the torpedo “listened” not for return sonar pings, which would be ice dumbly reflecting the sound, but for pings higher or lower pitched than emitted by the nosecone transceiver. But oddly, none of the return pings passed the doppler filter. None were upshifted or downshifted. Nothing but false returns from the ice.

  The torpedo was stumped. It was now 17 kilometers from the Kaliningrad, and the range to the enemy, the 666, had probably been much less at time of launch. The next line of coded instructions told the Magnum to continue to a range of 20 kilometers from its launch point, and if there were no hints of the target, to execute the default-turn-back and run until it either found the target on the return vector or reached a point 10 kilometers from the launch point.

  Twenty kilometers from the launch point the Magnum torpedo gave up. It had been unable to find the target and it was time to turn back and execute its nuisance-explosion. In response to its program, the Magnum ordered its rudder over five degrees, made the 180-degree turn in less than a minute and headed back and east toward the launch point. After 14.5 kilometers of backtracking without a sniff of the target, the Magnum initiated the arming of the nuclear warhead. It was, so to speak, resigned if disappointed. It would have been much more fulfilling to have detonated mere meters away from the 666. But at least its detonation 10 kilometers from its launch point would do some harm to the target. With the arming sequence begun, the Magnum had no thoughts about what would happen to it in the moments following the nuclear detonation. Like a human driving toward orgasm, the torpedo was a highly goal-oriented being. The only thing in its “mind” was getting to its detonation position and exploding. Never mind the aftermath.

  USS DEVILFISH

  The Mark 50 Hullcrusher torpedo in Devilfish”s tube had been waiting a long time. For over two hours its gyroscope had been spinning, its central processor had been awake and the fuel lines had been pressurized. It had been programmed with the solution to Target One ever since the target was acquired fifteen minutes earlier. Every few minutes the solution to Target One had been updated, making the Hullcrusher hypersensitive to Target One’s every move. The outer door of the tube was open. The small clearance between the tube and the torpedo was filled with water at outside pressure. The water had heated up, from the the nosecone, home to the flat sonar transducer, was cold, feeling the water temperature outside the ship. When a slight electrical signal came down the guidance wire at the torpedo’s stem section, the weapon “tensed.” The signal was the final target solution update, now locked in, as the control room fire-control console’s SET key was pressed. A locked-in solution meant that launch was less than a minute away. The torpedo was ready.

  “Ship ready!” Stokes called out.

  “Solution ready,” from Scott Brayton.

  “Weapon ready,” from Bahnhoff. Pacino paused. This was unprecedented, firing on a target without having sonar contact on it. Yes, this was a recipe for a miss, particularly under ice. But better to try and miss than sink with a full load of torpedoes. Pacino made up an order.

  “Shoot on last sonar bearing.”

  “Set!” from Brayton on Pos Two.

  “Stand by!” from Bahnhoff on the firing panel, taking the trigger to STANDBY.

  “Shoot.” Pacino felt a shot of adrenaline.

  “Fire.” Bahnhoff pulled the trigger to FIRE position. Without the usual underway noises of ventilation and SINS navigation system, the torpedolaunch sounded more violent than usual. The pressure-pulse hurt twice as much. Pacino forced a yawn to clear his abused eardrums from the pressure. Something about a warshot that made the launch sound different — this time the noise meant business.

  “Tube one fired electrically. Captain,” Rapier re
ported.

  “Conn, Sonar,” the sonar chief reported on the headphone circuit, “ownship unit, normal launch.”

  On the Hullcrusher’s port flank a relay opened as tube external power turned off. The torpedo was now on internal power, no longer dependent on the tube or the mother ship.

  As the connector separated, the prongs of the “in-water” sensor shorted out, and the sensor completed the first of several arming safety interlocks. The torpedo “heard” the sound of water flowing, just for a moment… it was the pressurized water from the torpedo-tube tank pouring into vents at the aft end of the tube to push it out of the ship. The torpedo underwent a powerful acceleration, like falling through a dark tunnel at supersonic velocity. The noise of the sudden flow was deafening.

  Would the torpedo “hear” its target? Behind the torpedo the guidance wire streamed out of one of the fixed vanes of its propulsor, and also out of the ship’s torpedo tube. The wire would remain stationary… the ship had a length of wire that allowed it to maneuver… and the torpedo let out its own wire to allow it to move. The wire allowed the weapon to be steered if the mother ship had a better fire-control solution. It also carried transmissions from the weapon to the firing ship when the torpedo had a valid detect on the target. The firing ship could tell when the wire became disconnected from the torpedo — which was usually an indication that the weapon had hit the target and exploded. As the torpedo tube and the Devilfish faded away astern of the weapon, a second safety-interlock contact shut the three-g accelerometer, confirming the launch. The three-g contacts completed a circuit to a grain-fuel canister next to the combustion chamber. The grain fuel then ignited, pressurized the chamber and brought it up to the fuel’s ignition temperature. As the temperature rose, the self-oxidizing fuel was injected and ignited, the turbine of the engine began to spin, already windmilling at 20 RPM — and the engine-rotor accelerated to transit velocity…