The low explosives lit off as the back half of the Gigantskiy vaporized in the explosion of the Mark 48 ADCAP countermeasure torpedo, and the high explosives detonated, compressing the plutonium fragments into a sphere, and nanoseconds later, the plutonium exploded, its plasma sphere engulfing the heavy water canisters, which started the fusion reaction, and the full one megaton yield of the torpedo lit the previously coal mine darkness under the ice into bright daylight. The explosion blew upward into thick ice, but the ten meter thickness of the ice canopy was unequal to the tremendous force of the explosion, the entire ice canopy blowing into splinters and shards and flying upward for a radius of three hundred meters, the violent expulsion of water vapor of the explosion rising to over a mile over the surface. The pressure wave from the blast hit the bottom and reflected upward, the shock wave becoming a cylinder around the blast zone and traveling away at sonic speed in all directions, until it encountered an ice wall to the west, blowing the ice wall to fragments.
On the other side of the ice wall was the huge hull of the launching ship, the
Tomahawk SUBROC unit one, in tube eleven of the aft Virginia Payload Tube, lay snug in its waterproof capsule, nestled in the vertical tube. It was connected to the BSY-1 battlecontrol system by a signal wire leading to the flank of the capsule and penetrating it and connected to the weapon’s electronics. The target location was programmed in and accepted, as well as the present position of the weapon. The warhead yield was dialed in at maximum, 250 kilotons of thermonuclear power. The signal wire from the battlecontrol system disconnected. The missile was on its own now, its battery keeping it alive until the turbine could start up in the near future.
The weapon felt the sudden intense acceleration upward as the launching system ejected it, a rocket motor directed into a reservoir of pure water at the base of the tube, flashing the water to high-pressure steam that acted like the gunpowder explosion of a cannon ejecting a cannonball. The cannister flew out of the tube, accelerating more as it rose out of the tube, but as the stern of the capsule cleared the tube, the pressure of the steam eased and the acceleration became negative as the weapon slowed. The steam created a bubble around the capsule and the steam and the cannister rose quickly toward the surface a hundred feet above, to the open water of the polynya formed by the first Gigantskiy detonation.
The weapon continued rising until the nosecone of it broached into the cold arctic air. As it did, a wet-dry sensor at the tip of the cannister detected dry air, and it activated twenty-four explosive bolts around the circumference of the cannister, blowing the nosecone cleanly off, the fiberglass of it tumbling end over end high in the air. As the nosecone reached the apex of its flight and started falling back toward the water, the missile’s first stage rocket engine ignited, and the missile roared out of the waterproof cannister and blasted out of the water, rising vertically up over the icy landscape. Behind it, the polynya grew smaller as the rocket motor roared, lifting the missile to a height of a thousand feet.
As suddenly as it had begun, the rocket thrust stopped, the solid rocket fuel exhausted. By then, an air inlet scoop had popped out, the scoop sucking in air. Another two dozen explosive bolts blew the rocket motor off the aft end of the weapon, the first stage tumbling back down toward the polynya, and as it did, the explosive blast of steam could be seen below as a second missile’s cannister broached into the open water.
