The hull diameter was much bigger than he’d expected, even though he knew every dimension, every available bit of data in existence about the Rising Sun. But it was one thing to know something intellectually, quite another to experience it in person, especially like this. Chu swallowed and concentrated, pulling his control yoke upward to ascend closer to the surface.
The heads-up display showed him at ten clicks, jogging speed, which was a disadvantage if the wake of the propulsor water jet pushed his submersible harder than his onboard computer could accept. A stray current from the wake could force him to surface and make him broach, a potential disaster. Being observed from a periscope was hardly a way to sneak up on a target submarine.
And he was so shallow that his speed didn’t afford much control here, where the Bernoulli suction force from the broad expanse of the hull would compete with the suction from the surface above. The submersible could either broach or slam into the submarine hull, both accidents having the potential to ruin the surprise.
Chu felt like he was walking a tightrope, failure on either side. The odds were against him, but he had done this before, a hundred times. He had logged over two dozen dockings with the practice target submarines, some deep, some at mast-broach depth, some fast, others hovering, and over two hundred dockings in the simulator at the Lushun base, and one actual successful approach on the Korean submarine. He could do this, he promised himself.
He brought the submersible higher, driving forward, beginning to overtake the slow submarine. The huge ship wallowed at mast-broach depth, rocking gently from side to side in the one-meter swells. It was time to put the Red Dagger in the danger zone, the narrow throat of water between the sub’s top hull deck and the surface.
He felt completely one with the submersible, its onboard computer an extension of himself. His eyes were wide, his nostrils flared, his forehead beaded with sweat, his breathing coming in gasps, an athlete running for the goal line. The view port showed the gray hull below him, looking like the top surface of a dolphin, the same coloring and texture. The silvery glint of the waves above him suddenly changed to a bright white. The dull gray of the submarine hull showed sharp lines of light shimmering over its surface, as if Chu were looking at the bottom of a swimming pool, the bright web of light moving and changing with the sunshine. The sun must have appeared from behind a cloud, Chu thought in the back of his mind.
A rivulet of sweat ran into his eye, forcing him to blink it away. He gritted his teeth, edging the ship deeper as he felt it start to stray toward the waves overhead.
Just as he evaded the suction pulling him upward, the suction of the hull pulled him back down. All this depth-control struggle would exhaust the onboard coils if he couldn’t complete the rendezvous in a few moments.
Again Chu wiped his mind blank — only the waves above, the sub below, and the heads-up display constituting his world. For the first time since putting the submersible between the sub and the surface, he allowed himself to read the digits of the heads-up display.
One number of the display read off the range to the aft lip of the sub’s fin. The second number showed him the distance to the aft escape trunk hatch just forward of the X-tail.
The display numerals confused Chu for a moment.
The distance to the escape hatch was negative — he had gone too far. The fin trailing edge was far ahead, but the escape trunk was behind him. The aft part of the submersible hull would actually be between the surfaces of the X-tail when the docking skirt was over the escape trunk — at least it would be if Mai’s data were correct.
Chu throttled back, allowing the submarine to surge slightly ahead. With the after escape hatch this close to the X-tail and the suction of the propulsor, the approach was much more difficult than it had been to the Korean ship, where the hatch had been far forward of the screw.
At least this ship had a thicker anechoic coating, the dolphin skin, designed to minimize drag and reflected sonar noise. It would provide a rubbery cushion in the event Chu smashed down onto the hull. Perhaps, he thought, it would be better to do that than prolong this energy-wasting dance with the submarine.
The numerals of the display rolled back until the docking skirt was within two meters of the calculated position of the hatch. Chu energized the bottom-scanning video camera at the docking skirt, looking for the hatch, and then released control of the submersible to the onboard computer to allow it to bring the vessel in for the docking. But as Chu released the yoke, the Red Dagger began to shake and oscillate, finally heading for the surface, then plunging toward the deck. Chu cursed and grabbed the yoke, frustrated and angry. The computer had failed him, and the dolphin skin surface of the ship was making the location of the hatch impossible to see.
Chu put the submersible close to the fin and again slowed down, this time knowing he would have to approach the hatch on his own. After five exhausting minutes he worked the submersible back to where it had been before, keeping station over the sub’s escape hatch.
He drove the craft on while searching the video image for the hatch. The more he tried to do it, though, the harder it got to control the submersible. Lo Sun would have to help him.
“Mr. First, quickly, do you have the docking-skirt video up?”
“Yes, Ad—”
“Fine, you talk me into the hatch. I can’t maneuver and look for the hatch at the same time. Computer’s broken. Hurry!”
“You’re at plus two, starboard one point six—”
“Dammit, just tell me how much to come left or right—”
“Back slow, come left, just a hair, good, ahead a half meter, more, more. Now! Down!”
Chu brought the vessel down to the deck of the submarine, the contact light, the surface of the sub rubbery.
“No, now we’re too far ahead. Don’t pump down yet.
Can you back us up? You’ve got ten centimeters, maybe less.”
Chu pulled back on the throttle, the suction from the sub keeping him down, the submersible sliding in increments until Lo called that he was centered over the hatch. Chu flooded the small ballast tank, trimming the vessel heavy so that it would stay down on the slippery hull. A high-pressure air bottle pushed air into the skirt and water out of a slot at the skirt bottom. The pump, at deeper depths, would suck the water overboard and allow the space to be filled with air. Since they were shallow, the air pressure alone pushed the water out.
The heads-up display showed the vacuum established.
He should be able to kill the engines, the powerful suction from the docking skirt keeping the two ships together.
Chu gently pulled back on the throttle until the engines were idling. He kept waiting for the disaster of the skirt failing or flooding, eliminating the link between the vessels, but the vacuum held. At last Chu cut the motors and toggled off the coil power, unbuckled his harness, and withdrew from the control couch. When he stood, shaking out his cramped limbs, he found he was soaked from head to toe with sweat. He wiped his forehead and accepted a towel and water bottle from one of his men.
Lo waggled his hands to loosen them up after spending the last hour pointing at display panels. Other than Chu and Lo and Wang — the pilot who would shut the hatches after the platoon invaded and then who would take the Red Dagger back to the seaplane — the men were all wearing their masks and scuba bottles. The canned air would prevent the men from breathing radioactive dust or steam from the reactor spaces. Once they were in the habitable command compartment forward, they would ditch the masks. Chu and Lo shrugged into their gear.