Ssn (1996) Page 12

  6.

  Ambush

  Cheyenne’s crew was well rested after their relatively relaxing stay on board the submarine tender McKee. Cheyenne had been rearmed and their food and supply stocks had been replenished. Captain Mackey was even looking forward to his next mission.

  According to naval intelligence, that mission was going to be a “breeze” compared to his last several—and Mack hoped they were right. By now, his officers and crew were combat-hardened veterans who had more than paid their debt to their country. If Mack had his way, he’d give each and every one of them a medal and a promotion for their service.

  The captain called the executive officer into his small stateroom. This was one of the few places where the captain could have a quiet moment to himself. He had asked the executive officer to join him because he didn’t always trust naval intelligence and he wanted a second opinion on the orders Cheyenne had received.

  When the executive officer arrived, Mack handed him the message. He didn’t say a word. He didn’t have to.

  The orders called for Cheyenne to enter into the Chinese-claimed Spratly Islands and patrol several of the now-abandoned oil rigs in the area, including the partially built rig bordering on Swallow Reef.

  The executive officer studied them for two minutes and then looked up. The look on his face made it clear that he wasn’t any happier than Mack was. A week earlier, naval intelligence had proclaimed those waters too dangerous to enter. Now they were claiming that they’d been deloused and were clear of all enemy submarines.

  Mack had gotten what he’d wanted—confirmation of his suspicions. Cheyenne had her orders, and she would carry them out, but she would be expecting trouble, no matter what those intel guys said.

  “Gather the officers,” he said. “I want them all in the wardroom in fifteen minutes.”

  Ever since he’d first met the executive officer, Mack had liked him and trusted his opinion. During wartime, Mack knew, one could never be too reliant on intelligence reports from thousands of miles away. The executive officer had agreed with his feelings on their orders and that made Mack trust him even more.

  Fifteen minutes later, the wardroom was quiet when Mack entered. He looked around at the assembled officers and decided to get right to the point.

  “We’ve been ordered to enter the Spratly Islands chain and patrol several oil rigs in the area that are believed to be possible locations for submarine supply depots,” he said. “Naval intelligence doubts this finding, but they have sent us to investigate nonetheless.”

  Because the intelligence analysts didn’t think that they would find anything in the area, CTF 74 had decided it would be cost efficient to load Cheyenne with only twenty Mk-48 torpedoes; no Tomahawks and no Harpoons. So even if Mack did find a remote Chinese operating location, he couldn’t attack it with Tomahawks as he would have liked to. He was ordered to report back, and then the Navy would order an air strike.

  He hated this kind of thinking.

  The assembled officers were silent, waiting for him to continue. “Naval intelligence reports that due to our successful actions during the past several weeks, as well as the actions of the rest of the Navy, the Chinese units in the area are running low on supplies and morale. They expect that, at the most, we will come into contact with only a handful of submarines in these waters.”

  Mack looked around the room, assessing his officers. “This mission is supposed to be an easy one,” he said, “but you all know what that means. It just means we have to be extra careful and keep on our toes. I don’t like being that close to Chinese-occupied waters any more than you do. But we have our orders.”

  After the usual number of questions, the wardroom was cleared and the captain went back to his stateroom, where he again examined his orders. He still didn’t like what he was reading.

  Mack looked at the chart he normally kept in the wardroom. It was one of the few good charts he’d ever seen of the Spratly Islands. The chain was oval, shaped roughly like a football, with four islands that Cheyenne needed to patrol.

  As Mack examined the chart, he decided he would steam silently from the north into the waters surrounding Discovery Great Reef. From there, he would proceed in a counterclockwise direction, continuing west and south until he arrived near Cuarteron Reef, right in the center of the oval.

  From there, Cheyenne would travel to Swallow Reef, near the southern border of the islands, and then sail northeast until she arrived at her last search area, Carnatic Reef. Assuming that intel was right—an assumption Mack was not prepared to make—and the area was clean, Cheyenne would then continue on to the north to await further orders.

  Cheyenne was now passing the island of Palawan to the east. Navigating the remaining 200 miles in the narrow but deep channel leading to Mindoro Strait would require a number of GPS fixes en route. The submarine tender McKee, from which he had just finished rearming, would remain on station in the Sulu Sea until ordered by CTF 74 to relocate.

  After the recent submarine attack on McKee, the Independence and the Nimitz Battle Groups had each decided to part with one ASW helicopter, and the two LAMPS III helos were now being flown to McKee’s position.

  The SH-60s would be operated from McKee’s landing pads in order to protect the tender from any possible future submarine threats. The SH-60Bs were also equipped to carry the Penguin antiship missile, which would offer McKee an antisurface defense as well. The Navy would not be taking any more chances by sending a defenseless tender into the line of fire.

  One other good thing came out of that attack on McKee—at least from Mack’s point of view. McKee’s captain was very appreciative of Cheyenne‘s timely rescue and had provided as much fresh fruit as Cheyenne’s storage spaces would allow. Fresh fruit was scarce on board a submarine and stocks often ran out quickly. This gesture on the part of McKee‘s captain was greatly appreciated, and while the fruit would not last long, it would help ensure that the beginning of Cheyenne’s cruise would be enjoyable.

  Having found a Ming SSK in the Sulu Sea, Mack could not afford the luxury of running on the surface until clear of Mindoro Strait. Still, the channel out to the Sulu Sea was narrow and treacherous, so Mack decided to supplement the GPS fixes with occasional active sonar. The threat of other Chinese submarines was real, but so was the threat of running into the side of the channel.

  Once past the shallow waters of Mindoro Strait, Cheyenne accelerated to twenty knots, on course 300 toward the start of her counterclockwise search of the Spratly Islands. Upon arrival, Mack ordered the OOD to run at four knots until they determined that the area was clear before continuing on their way.

  The TB-23 towed array was streamed to help in the search of the deep water in case there were Chinese SSNs trying to slip in from the north. After a careful sonar search, Cheyenne increased speed to full and altered course for Discovery Great Reef.

  The more Mack thought about this current mission, the less he liked it. He was all too aware of how easy it would be for a diesel submarine like a Kilo to hide in the island waters near the oil platforms. An enemy submarine could lie in wait near the bottom of the shallow water, hiding until Cheyenne came within torpedo range. They could even bottom without damage, since the Chinese diesel submarines didn’t have a GRP (glass-reinforced plastic) sonar dome or seawater cooling for a steam propulsion plant to worry about. Captain Mackey didn’t like that thought at all.

  Mack decided that once he was within twenty-five miles of each search area, he would reduce Cheyenne’s speed to eight to ten knots and that once he was with ten miles he would slow to four to seven knots. He didn’t want anyone sneaking up on them, and running slow was the best way to keep Cheyenne quiet.

  When Cheyenne was twenty-five miles north-northeast of the Spratlys, Mack proceeded to the control room, looked at Cheyenne’s position on the quartermaster’s chart, and then ordered the OOD, “Slow to ten knots.”

  “Slow to ten knots, aye, sir.”

  The change in the speed of
the submarine, while sudden, was not overly drastic for the crew. They had gotten used to the rough riding of a submarine in close combat.

  Hours before, Cheyenne had shifted from the TB-23 to the TB-16 towed array. The sonar operators were listening quietly, but heard nothing on the towed array or the spherical and conformal sonars, and the sonar supervisor soon reported that there were no contacts. Mack was pleased with that report. He knew that if they were to encounter an enemy submarine, they would be in for a dangerous, shallow water fight.

  Cheyenne was not at home in coastal waters like these. The Los Angeles class submarines were designed for blue water operations. Cheyenne and her sister ships performed best in the open ocean. While they still performed well in areas like the South China Sea and, more specifically, the Spratly Islands, their superiority gap was narrowed markedly.

  A Los Angeles class SSN was 360 feet in length—nearly 100 feet longer than an Alfa submarine, and the Chinese and Russian Kilo submarines were smaller still. The Kilo was a perfect weapon system for these dangerous waters. Measuring 229 feet, it could weave in and out of tight spots that Cheyenne would not even want to venture into.

  As Cheyenne approached Discovery Great Reef, Mack decided to remain relatively shallow. That would allow Cheyenne to copy any radio traffic that might be broadcast to them. In addition, he didn’t trust the water depths in this area. He figured he had a better chance of running aground than he did of being detected by the enemy.

  When Cheyenne crossed the 100 fathom curve inbound for Discovery Great reef, Mack ordered, “Come to periscope depth.”

  Cheyenne had already been running shallow at 200 feet. Now, however, Mack would use the periscope to check out the notorious “oil platforms.”

  “Conn, sonar,” the sonar supervisor called a short time later. “I think we’ve got a contact on the towed array. It sounds faint, but it may be a submarine ... although the computers haven’t been able to confirm a thing.”

  The contact was currently too weak for Cheyenne’s sonar operators to do much with. Mack made a mental note to keep checking on it, though. He was sure that if this was a submarine they were picking up, Cheyenne would be going after it soon.

  Mack was also sure that whatever they were picking up had not yet detected their own presence in these waters. Cheyenne was currently running at only three knots to minimize the periscope “feather,” the wake caused by the periscope barrel as it moved through the air-water interface, and she was nearly as quiet as she could be.

  “Captain, we are currently seventeen miles northeast of the first oil rig,” the navigator reported.

  “Sonar, Captain, do you have any additional information to report on that contact?” Mack asked.

  “Conn, sonar, we classify Master 48 as a probable submarine contact to the southwest. It appears that it’s on the other end of the abandoned oil rig from our position. It’s barely making a sound, though.”

  Mack acknowledged the report and ordered battle stations manned and the towed array housed. He still didn’t know for sure what that contact was, but he had the feeling that Cheyenne was about to go into battle once more.

  Southwest of Cheyenne, at the other end of the abandoned oil rig, a Chinese Kilo submarine was getting into position near Discovery Great Reef. The Kilo was running silently, and its captain was confident that they could not be detected. But then, based on estimates from Chinese intelligence, he did not expect any American SSNs to be near his position for at least another day.

  The Chinese intelligence machine was very different from its American counterpart. The Chinese focused their intelligence on the human aspect, or HUMINT, while the Americans focused their intelligence on ELINT—electronic signals interception and satellite photography.

  These differences made sense in terms of the backgrounds of the two countries. China had a massive population, with citizens and former citizens scattered around the world. America, on the other hand, had massive quantities of money that they could use to invest in their defense industry.

  These differences came into play off the Spratlys. Cheyenne, with her advanced technology and sophisticated sonar equipment, was able to pick up traces of the Kilo. The Chinese boat, however, was relying more heavily on human observers—but Cheyenne’s submerged transit of the Philippine Islands area had precluded any HUMINT by Chinese observers on the islands.

  The captain of the Chinese Kilo finally arrived in his position slightly more than one nautical mile west of the oil platform. He planned to wait there in silence for passing American naval vessels, hoping for some to venture close enough for him to strike.

  He didn’t know it, but he was about to get his wish.

  “Conn, sonar,” reported the sonar supervisor, “we just lost contact on Master 48.”

  “What was the last position of Master 48?” Mack asked the fire-control coordinator.

  The executive officer, who was acting as fire-control coordinator for this watch, said, “Captain, Master 48 was about nineteen thousand yards west of the Discovery Great Reef oil rig. Do you think she heard us?”

  The question was a good one.

  Could they have heard us? Mack wondered. The most probable reason that they would lose contact with a submarine was either that the enemy submarine’s noise was being shielded from Cheyenne‘s sonar, possibly by a thermal layer or the surf noise, or that the submarine had detected Cheyenne’s presence and had either stopped or was running silently. The silence indicated that if there was a submarine out there, it was probably a Chinese diesel boat, running on its batteries.

  Slowly, Cheyenne approached the oil rig, which lay within one mile of Discovery Great Reef. The water was extremely shallow in this area and the huge rocks surrounding the now dilapidated oil rig served to shield the diesel’s sounds.

  Cheyenne‘s passive sonar suite was severely degraded in the shallow environment of the littorals. In this environment, active sonar would work almost as well as passive, if they used MIDAS to discriminate between rocks and a submarine’s longer hull, but Mack didn’t seriously consider the idea. He knew that using his active sonar would give away Cheyenne’s exact position. He’d rather have both submarines blind than give away his position to the enemy.

  Through the periscope, Mack could see the Discovery Great Reef oil rig. At a glance, he could tell that it had been destroyed during the Chinese occupation of the island. But he needed to give it more than just a glance. He was supposed to get some accurate photographs of the rig for intelligence back in Washington. In addition, he needed to ensure that the rig was not being used as a Chinese submarine depot that could rearm or refuel Chinese SSKs.

  He made another quick circle as he “danced” the periscope around the surface. He could find no evidence that the rig was being used for anything—or that it was even in the process of being repaired—but still he was cautious. This was a very dangerous place for Cheyenne to be running at periscope depth.

  Six nautical miles away, or about 12,000 yards from Cheyenne’s current position, the Chinese Kilo submarine was operating in its silent mode—running on its batteries. With no noise coming from their own ship, the Chinese sonar operators listened carefully to their low frequency sonar, searching the waters for the sound of any American vessels.

  They heard nothing.

  The Chinese had been loitering here, running silently on their batteries, for seventeen hours, keeping their depth shallow at 45 feet and their ears open. The captain was waiting for the Americans to walk into his trap.

  After seventeen hours, however, the captain of the Kilo grew impatient. He’d had enough of this waiting. Slowly the Kilo pulled out of its hiding spot and began to pick up speed. Its captain had decided to make a run at six knots, slowly and quietly circling Discovery Great Reef, searching for any American naval vessels.

  As soon as the Kilo moved, it lost its protection against American sonars, and Cheyenne heard it.

  “Conn, sonar, we just reacquired Master 48. It’s a Kilo,
single six-bladed screw. It just increased speed to six knots and it’s heading north.”

  A short time later a BSY-1 operator reported the Kilo’s range, and Mack knew Cheyenne was in trouble. The Chinese submarine was only 11,000 yards away, which meant that Mack had unknowingly brought Cheyenne well within weapons range of the Chinese Kilo and her TEST-71 homing torpedoes.

  “Make tubes one and two ready,” Mack ordered. “But do not open the outer doors!” He emphasized that. They were too close, and he didn’t want to give the Kilo any chance of detecting their location.

  “Make tubes one and two ready but do not open the outer doors, aye, sir.”

  Mack had a problem. He had the drop on the Kilo, but he didn’t have much maneuvering room. If the Kilo got off a return shot, Cheyenne could be in trouble.

  And that was the least of his worries. His bigger problem was his lack of intel. Were there other Chinese submarines out there? Naval intelligence said no—but they’d missed one already. Who was to say they hadn’t missed more?

  This was a problem because he would give away his position as soon as he fired on the Kilo—and even if that submarine didn’t fire back, there could be others hiding in the shallow water waiting to pounce.

  Captain Mackey ordered Cheyenne rigged for ultraquiet. He wanted every effort made to ensure that nothing alerted the Kilo to their location. Word was quickly passed to all compartments over the sound powered phones. Non-vital equipment was quickly secured. The crew whispered when they spoke, wondering what would be next.

  On board the Chinese submarine, the captain was growing frustrated. He was assigned to keep watch for American submarines, but he knew that he would never hear them unless they were close enough to fire their Mk 48s. Even under ideal circumstances his passive sonar was never up to par with the American BSY-1 system, but in these shallow waters his Russian passive sonar performance was even worse.