Tiger's Claw: A Novel

above the surface. He immediately saw the helicopter, moving away from them. He locked onto the helicopter and hit the laser rangefinder. “Mark.”

“Range three thousand two hundred meters.”

“Simulate fire two IDAS.”

“Simulate fire IDAS . . . one away . . . two away.” Had they actually launched the wire-guided missiles, they would take steering cues from the periscope and laser marker to home in on its target.

“Good job,” Yao said. “Down periscope. Steady up on two-two-zero, simulate reloading tube three with IDAS. How far until the first escort?”

“Approximately ten kilometers, sir.”

Well within the active sonar range of a medium- or large-size escort vessel, Yao knew, but outside their own passive sonar detection range. Stealth was very important now. They made temperature measurements as they ascended and descended, which improved the computer models for determining thermoclines—marked bands of different temperatures through the water that might deflect sound or sonar—so they could pick the proper depth to head toward the target, but it was all educated guesswork. It was akin to a bowhunter stepping quietly through a forest toward where he thought the deer would be, using everything possible—wind direction, foliage, silence—to close in undetected. In the end, it usually came down to patience and luck.

Just then: “Single sonar ping, sir, bearing two-four-zero.”

The Communists had made a mistake—he used his active sonar to try to get a fix on them, which instead gave away his own location. “Getting a little anxious, are we?” Yao said under his breath. “Now, it would really help if you . . .”

“Second single ping!” the sonar operator reported, his voice still muted but noticeably excited. “Bearing two- four-seven, heading one-zero-zero, approximate range eight kilometers!”

“Up periscope,” Yao ordered. He turned the periscope tube to the proper bearing, then slowly raised it. A few clicks of magnification and he had the destroyer in his crosshairs. “You are mine, pigu,” he said in a low voice. He took several photos. “Down periscope,” he quietly ordered. “Stand by for simulated torpedo attack, crew,” he spoke on the intercom. “Flood tubes two and five, keep the outer doors closed, acknowledge.”

“All outer torpedo doors closed and verified, sir.”

“Very well. Simulated only, match bearings . . . simulate fire one . . . simulate fire two.” The WS-2A5 torpedoes were the standard Taiwanese torpedoes, designed and built in Taiwan but designed after the American Mk-48 torpedo. They were wire guided, with passive sonar detection as primary terminal guidance and active sonar guidance if the wire was cut and for a final range and bearing to the target. The wire transmission was two-way, so not only could the torpedo operator on the sub steer the torpedo through the wire, but the torpedo could send sonar signals back to the sub as it closed on its target. The torpedo swam as fast as fifty-five knots, slowed to forty knots to take a terminal active sonar fix, then sped up again to close in for the kill.

“Make your course two-one-zero,” Yao ordered. He turned to his executive officer, Zun Khong (Commander) Chein Si-yao. “Now we go after their carrier, Si-yao.”

“It is risky, sir,” Chein said. Chein Si-yao was far younger and less experienced than Yao, on his first extended cruise aboard the Avenger. “The battle group is only eight kilometers away, and several helicopters are airborne. If they start hammering away with their active sonars, they can swarm us.”

“We will let them sail past, and then try to come up behind the Zheng He for a shot,” Yao said. “I am not going to let this opportunity pass. The Communists expect everyone to run away with fear when they sail their big carrier battle group around—they will not expect anyone to pursue them.”

“Simulated strikes on Communist destroyer complete, sir,” Chein said as the seconds ticked past on his watch. “Successful engagement. Congratulations, sir.”

“Thank you, Commander,” Yao said, “but I want that carrier next. Continue scan for the Zheng He. Range and bearing as quickly as possible.”

EIGHT

ABOARD THE PLAN AIRCRAFT CARRIER ZHENG HE

THAT SAME TIME

The phone from the flag bridge rang, and Lower Admiral Weng Li-Yeh, captain of the carrier Zheng He, picked it up immediately. “Yes, Admiral?”

“Any sign of that traitor submarine yet?” Rear Admiral Hu Tan-sun, commander of the Zheng He carrier battle group, asked.

“We have it narrowed down to less than a hundred square kilometers, sir,” Weng replied. “The Y-8 radar operators thought they had spotted a periscope very briefly about a half hour ago, but the sea state is a little choppy so radar reports are not totally accurate.”

“How about the diesel detectors?” Hu asked. The Y-8 patrol plane had the capability to sniff the air for telltale signs of diesel exhaust to alert it to the presence of diesel-electric submarines.

“The Y-8 is patrolling too close to the battle group, sir,” Weng replied. “Diesel detectors will not be reliable unless they fly farther out. Besides, if the target is trying to do simulated attacks on our group, he will likely be running on batteries only.”

There was a slight pause, then Hu said, “How many antisubmarine helicopters can we launch into the area right now?”

“We can launch four, sir,” Weng replied. “Four of our escorts have helicopters, but I think only two are configured for antisubmarine operations at this time. A total of six, sir.”

“Weng, we had intelligence that the traitors were going to send a submarine after us—we should have had all helicopters configured for ASW.” Another pause, then: “Launch all available ASW helicopters into the search area immediately.”

“All of them? But, sir, the Taiwanese sub will be alerted that we are searching for him the moment he detects multiple sonars. I recommend . . .”

“Weng, we know the traitor is on the way, and we have a good idea where he is,” Hu snapped. “The last thing I want is for the traitors to come within torpedo range of this ship—or worse, actually take a shot at us. Launch the helicopters immediately!”

ABOARD THE TAIWANESE SUBMARINE AVENGER

A SHORT TIME LATER

The search for the Zheng He did not take long: “Got him!” Yao whispered excitedly. The profile of the carrier was unmistakable through his periscope even at this range. “Bearing one-nine-one.” He hit the laser rangefinder. “Range twelve kilometers, speed twenty, heading zero-eight-zero. Transmit target position and the periscope photo of the second engagement to fleet headquarters.”

“Transmission sent, sir,” came the response a few moments later.

“Very well.” He made a fast 360-degree scan of the horizon. There was one escort ship to the west. Yao got a photograph and a position on it. “Periscope down.” Twelve kilometers was right at the edge of the torpedo’s envelope, and it was perpendicular to their course so it was an even more difficult shot—they had to close in. “Steer one-seven-zero, make fifteen knots, set your depth one hundred meters.” He estimated the carrier battle group was probably making no more than twelve knots, so he could close in slowly without going to full underwater speed. The Zheng He could probably sail at almost thirty knots when launching aircraft, which was far faster than the Avenger’s top underwater speed, but within its protective cocoon of ships it had to slow down so the others could keep up. “Let us get this one, men. I want a picture of a dead Communist carrier on the admiral’s wall by tomorrow morning.”

“Sir,” Chein said, “we are nearing our maximum submerged speed. We are exceeding ultraquiet parameters.”