Free Deep Sound Channel by Joe Buff

booster rocket's firing," Sessions shouted as a not-so-distant rumbling came over the speakers. "It's gone to supercavitating speed inside the vacuum bubble! . . . One hundred knots and accelerating!"
    Jeffrey eyed the sonar console. "Can we outdistance the weapon's final sprint?"
    "Negative, sir," Sessions said. "We'll be in lethal radius when the warhead blows at endof-run."
    "And we can't hit something that small with an AD-CAP," Jeffrey said. "Captain, recommend we fight fire with fire."
    "Concur," Wilson said. "Load tube eight with another Mark 88. Set it for low, repeat low, yield, dot zero one KT, a snap shot on the incoming torpedo's bearing." Ilse watched as Jeffrey watched his console screens. Again lights blinked as he replayed his special weapons litany. "Security alarm!"
    "Handling authorized," Wilson snapped.
    "Armed guard is in position," Jeffrey said, talking faster and faster. "Electronic locks are bypassed, mechanical locks are broken. Weapon loaded in tube eight. A-wire is connected, special weapons enabler tool connected."
    "I've relayed the PAL code," Wilson said.
    "Green light!" Jeffrey said. "Breach door closed! Recommend a preset running depth three thousand feet."
    "Concur," Wilson said. "We'll command-detonate through the fiber-optic cable."
    "Sir," Jeffrey said, "we'd better launch bows-on. We can't afford to lose the wire."
    "Concur," Wilson said. "Cut the wire, tube seven. Close muzzle doors and drain the tubes, tubes one through seven. Shore up the inner door tube eight." Jeffrey confirmed and then relayed the instructions, his voice clinical and clear. "Sonar, we need your absolute best estimate of that torpedo's range and speed. This is going to be close."
    "I'm passing them to Combat Systems now, sir," Sessions said, "but that thing's hard to model. It's still accelerating, now two hundred knots!"
    Wilson grabbed the 7MC. "Maneuvering, Conn. Stand by for severe control surface movements. Lock down the hydraulic ram relief valves." Wilson paused for the acknowledgment. "Expect a sudden back flank engine order. When it comes, give me everything you've got, but for God's sake don't trigger a reactor scram." He paused again. "Yeah, that's good, take it to a hundred eight percent." Wilson hung up the mike. "Helm, hard right rudder, make your course zero two zero. Make your depth three thousand feet smartly."
    Challenger pitched up and banked into the turn, trading velocity for altitude. Ilse was pressed into her seat. Her console showed their speed was dropping fast, as their heading swung through 180 degrees. The visceral rumbling from aft got louder. The rumbling over the speakers got louder too, as did the awful dings. A relentless robot'
    s coming for us, Ilse told herself. Those men we killed are reaching from beyond the grave.
    "How many?" she said out loud.
    "What?" Sessions said.
    "How many did we kill?"
    "Two dozen on each boat."
    "XO," Wilson said, "when should we fire?"
    "The sooner the better, Captain," Jeffrey said. "The Mark 88s are rated to our test depth."
    "We can't risk a failure," Wilson said.
    "Six thousand feet, then, sir?"
    "Four thousand," Wilson said. "Let's make really sure." Wilson glanced at a depth gauge.
    "Chief of the Watch, pump negative. Pump variable ballast to bring the boat up faster." Ilse felt a repetitive labored clunking from below. Their rate of climb increased but only slightly.
    "Sir," Jeffrey said, "recommend retract the foreplanes—they might snap off or jam from shock."
    "Helm," Wilson said, "retract the foreplanes."
    "Recommend we level off at three thousand feet before our weapon detonates," Jeffrey said. "It's best to take the blast bows-on, show a minimum profile, protect our side arrays and pump-jet."
    "Concur," Wilson said.
    "Three thousand's the depth of minimum danger this close in," Jeffrey said, "the tight part of the hourglass. Higher up the blast cone spreads as it lifts the surface; deeper down the counterpressure widens as it hammers toward