On that cautionary note, Mack concluded the meeting and the officers went back to their previous duties.
As Cheyenne pulled away from the Independence Battle Group, Mack thought about the dangers of this new mission. He and his crew had not had much experience with encountering naval mines, but he knew that they presented a great threat to all naval vessels, including submarines. During the 1991 Persian Gulf War, the only naval casualties the U.S. suffered came from two inexpensive and low-technology mines. It was an ironic twist on modern warfare, thought Mack, that a mine costing a few thousand dollars could sink a billion-dollar submarine like Cheyenne if the mine were to come into contact with her hull.
As soon as the meeting in the wardroom was complete, Cheyenne began her long trip north from Independence. USS Bremerton would be leaving the South China Sea and returning to the Indian Ocean. USS Columbia would stay with the Independence Battle Group, acting as ASW escort, in the same SSN(DS) role Cheyenne had played so many times.
“Make your depth four hundred feet,” Mack said.
“Make my depth four hundred feet, aye, sir,” the OOD said, acknowledging the order.
“Speed twelve knots,” Mack added. This order was also repeated.
There was no emergency rush for Cheyenne to get to the Formosa Strait. Safety was Mack’s primary concern. He would much rather get to his destination slowly and quietly than to arrive there after having to fight his way up north.
Besides, Mack didn’t want to announce his position to the Chinese navy. The strait between China and Taiwan was their home waters, and held the threat of warships coming from all directions. There were four Chinese naval bases within range of Mack’s destination. Each of those bases could send submarines, attack craft, or destroyers and aircraft after Cheyenne if they knew she was in their waters.
Which meant, Mack knew, that he would have to be sure that they didn’t find out Cheyenne was there.
Mack had expected the entire cruise to take slightly more than four days. At the end of the third day, Cheyenne had passed Zhanjiang Naval Base in southern China and was approaching Hong Kong exactly on schedule. So far, she had not detected a single Chinese naval contact, possibly because the Chinese navy was still regrouping after their humiliating loss to the Americans south of the Spratly Islands.
That string ended at the end of the third day.
“Conn, sonar,” the sonar supervisor reported. “We have a sonar contact bearing 200. Sounds like a surface ship.”
Mack was in the control room when the report came in. He decided that the contact was probably coming from a ship from the naval base directly to their southwest. The normal watch station BSY-1 operators started examining the information to attempt to determine the range to the contact.
“Conn, sonar,” the sonar supervisor said, “we have active sonars indicating that there are two Hainan fast attack craft — high — frequency sonars.”
With the section fire-control tracking party manned, the BSY-1 computers began to get the information needed to determine Cheyenne’s range to the targets.
“Conn, sonar, the active sonars are very far away. This is very probably a convergence-zone contact. According to our calculations, they are pinging from over thirty nautical miles away.”
“Sonar, conn, aye,” responded Mack for the OOD. “Keep tracking those contacts.”
Mack didn’t intend to do anything about the Hainans — not unless he had to. He still wanted to stay silent and undetected, if possible. On the other hand, he couldn’t afford to arrive at their destination tailed by a bunch of angry Chinese patrol craft.
Mack needn’t have worried — at the moment, anyway. The Chinese patrol craft knew nothing of Cheyenne’s transit north. They had gone active to test out their equipment, not because they suspected there was a U.S. SSN in the area. The Chinese craft, built in the early 1960s, had recently been fitted with a new active sonar and their captains often enjoyed using this during training exercises. Their upcoming mission, however, was anything but a training exercise. The two Chinese Hainan class fast attack craft had been fully loaded with twelve mines, and when they reached their assigned location they would begin deploying these naval mines from their mine rails. After they had evaluated their new sonars, the Chinese captains would continue on their assigned mission.
After fifteen minutes of tracking the Hainan attack craft, Cheyenne’s sonars lost contact with the two Chinese boats. They reacquired the two patrol craft as Cheyenne began to enter the strait.
Mack had gone back to the sonar room. After reporting the contacts to the OOD, the sonar supervisor said, “Captain, we’ve just acquired the two Chinese craft again. They must have gone up the eastern coast of China. Bearing is 355.”
Mack went back to the control room. “Do you have the range to the Chinese active sonars yet?” Mack asked.
“Not yet, Captain, but we should have it ready soon,” the OOD answered. He had worked hard with his section fire-control tracking party, perfecting their technique, and he was proud of them.
Less than a minute later the section fire-control tracking party had an answer to Mack’s question.
“Range is 68,000 yards, Captain.”
“Conn, sonar, our Chinese contacts have stopped pinging, sir,” the sonar supervisor said. “I’ll bet that they’re laying mines.”
The two Chinese craft were nearly forty miles to the north of Cheyenne. One by one their Russian-designed MAG moored contact mines were pushed over and dropped into the water via the mine rails aboard the small craft. These mines were based on technology that was nearly one hundred years old, but they still presented a serious threat to Cheyenne.
“Mark that area as a minefield,” Mack said, pointing to the area on the plotting table where they believed the Chinese ships to be operating. “If at all possible, we want to stay clear of that zone.”
“Aye, Captain,” said the auxiliary electrician forward as he looked up from his plot. He was the plotter for his watch section, and, like all the sailors on board Cheyenne, he took pride in his performance and his professionalism.
Mack did not know what types of mines were being laid in the Formosa Strait, but he did know that even the most basic, least expensive underwater pressure-sensitive mines could limit his operation. He hated to think that the Chinese could be laying some of the more advanced bottom-moored influence and acoustic mines such as the type employed by the U.S. Navy.
For now at least, although Mack didn’t know it, the Chinese preferred the low-cost mines to the high-tech, expensive ones, and the two Chinese craft were laying only pressure-sensitive types. These were perhaps the lowest-technology and least expensive naval mines a nation could buy. The MAG was a standard Soviet mine that was supplied to the Chinese throughout the early 1960s. One of the benefits of the MAG mine, however, was that it could be laid in water up to about 1,500 feet deep. This made them perfect for attacking submarines such as the American Los Angeles class SSNs.
As Cheyenne approached the southern entrance to the Formosa Strait, the communicator came to the control room to deliver a message to Mack.
“Captain, we just received an ELF message from Nimitz asking us to come to communications depth to receive a message from them over SSIXS.”