SSN

1. First Blood

The USS Cheyenne, a Los Angeles class nuclear attack submarine, cast off the tugboat’s lines at precisely 0100 on 12 August 1997, and moved under its own power into the dark waters of San Diego Bay. Astern of Cheyenne, the lone tugboat hauled in the lines and headed back to its berth at the San Diego Naval Base, headquarters of the Third Fleet.

The atmosphere aboard Cheyenne was taut with pre-mission tension. Her crew had performed admirably during her abbreviated shakedown cruise, but now she was on high alert and headed into almost certain conflict.

A few years earlier, as a result of the post-Cold War defense drawdown, the Third Fleet had relocated from Pearl Harbor to San Diego Naval Base. With the Chinese moving on the Spratly Islands, Cheyenne had been ordered to ready for deployment. She was now on her way from her berth at the Ballast Point Naval Submarine Base to the Pearl Harbor Naval Submarine Base to complete her outfitting. From there she would take up station in the South China Sea.

Cheyenne was the newest attack submarine in the U.S. Navy. She was also the last of an era. Given the hull number SSN-773, Cheyenne was the last of sixty-two Los Angeles class nuclear attack submarines to be funded by Congress. Built by Newport News Shipbuilding in the Virginia town of the same name, Cheyenne was 360 feet long and displaced 6,900 tons. She was equipped with the latest advanced weapons and sensor systems.

Cheyenne’s pressurized-water, S6G General Electric reactor had been critical for some time and the OOD (officer of the deck) had earlier passed the word, “Rig Ship for Dive.” When she was farther away from land, reaching the water west of Point Loma, where it was deep enough for the submarine to dive, sailors on board Cheyenne completed readying the submarine for submergence. From the sonar room to the torpedo compartments, sailors hurriedly confirmed that all was well in their compartments. The final message came back to the OOD, “Cheyenne is now rigged for dive.”

Captain Bartholomew “Mack” Mackey was pleased with both his ship and his crew. A big man, Mack had been engineering officer of an earlier 688, and executive officer and plank owner (new construction crew) of an improved 688-like Cheyenne—the 6881 USS Greenville (SSN 772), Cheyenne’s predecessor at Newport News. Mack was a rising star, two years deep selected for O-5 (Commander) and two years deep selected for O-6 (captain). Mack was a real captain, not just in terms of the Navy tradition of referring to a commanding officer as “captain,” but in pay grade as well.

Mack knew his crew had heard the rumors of a possible war with China. The recent Chinese actions concerning the U.S.-flagged Benthic Adventure, a United Fuels Corporation prospecting ship sailing in international waters off the Spratly Islands, had been considered by many in the United States to be an act of war. Even more blatant was the Chinese invasion of the long-contested Spratlys.

But Mack knew the rumors were true. As of 2 August, a virtual state of war had existed between the United States and China. On that date a Chinese Han class nuclear attack submarine came within striking distance of the U.S. aircraft carrier Nimitz with what appeared to be hostile intentions. In defense of Nimitz, an American escort submarine sank the Han, killing all aboard the Chinese vessel.

The story had saturated the news. There had been no further hostile action taken by the Chinese military, which led many experts to speculate whether they could have learned their lesson. That was, however, one nice thing about being on a submarine. One didn’t have to worry much about news. Attack submarines often stayed out on missions for as long as six months, surfacing for food and supplies when they were needed or visiting the various ports to which they had been assigned.

News was not the job of Cheyenne—theirs was a much more important mission: proceed to Pearl Harbor and ready herself for potentially imminent hostilities with mainland China.

The submarine submerged when she was ready, slowly at first and then more and more quickly. When she was underwater, the OOD began the transit by turning the submarine in a southwesterly direction — the most direct route for Pearl Harbor.

With the ship underway submerged, Mack was able to concentrate on the main obstacle to his mission, the possibility that Chinese nuclear attack submarines might be lurking along his path. His orders were clear: If Cheyenne were to come into contact with a Chinese vessel, she was to proceed with the utmost caution and attack only in self-defense. In other words, Mack knew, Cheyenne was free to fire only if she was fired upon first. The United States was not at war yet—“yet” being the operative word. When Cheyenne arrived at Pearl she was to load up on weapons and food needed for the possibility of a long cruise — one that could turn into a combat operation.

There was not much room on a submarine for storing food, so crates containing the canned goods that the crew needed to eat were loaded into the passageways, one on top of the other, making a temporary floor upon which sailors would walk until the food was ready to be eaten. As the crew consumed the food, the floor would grow shorter. Until then, the passageways would be a very dangerous place for taller members of the submarine crew. They would have to walk with their heads hunched down to avoid hitting overhead pipes and wireways.

As Captain Mackey walked toward the tiny wardroom he’d be using as the briefing room, he grinned at the thought that everything from canned tomato sauce to string beans was stored beneath his feet.

Cheyenne was two hours from San Diego Bay. Travelling at twenty-six knots, this put her fifty-two nautical miles from home.

Entering the wardroom, Mack motioned to his officers to sit. “As you are all aware,” he said, “we are currently in a highly tense environment due to the recent hostile actions taken by the Chinese military.” He was careful to point out that these aggressive actions were by the military — not, as the media often claimed, by the people or the politicians. “I would just like to inform all of you that we received a message that a Canadian P-3 Orion operating on a training mission out of San Diego thinks that they may have picked up a submarine 237 miles southwest of our current position. They even got positive MAD (magnetic anomaly detection) contact, but they lost contact after tracking the submarine for about twenty minutes. The P-3 crew is pretty confident that what they found was an SSN. Naval Intelligence thinks it may even be one of the Chinese Han class of nuclear attack submarines, but up to this point they haven’t been able to confirm anything. We have been instructed to keep our ears open for this possible contact while at the same time proceeding as fast as we can to Pearl so that we can arrive safely on station in the South China Sea. We are to avoid taking any actions against the submarine — unless, of course, he tries to kill us.”

The officers took this news in stride, and while the meeting was not as rousing as the captain had hoped, it had gotten his point across. Word would soon be buzzing throughout Cheyenne that they would be on the lookout for a nuclear attack submarine, possibly Chinese, lingering far too close to United States waters for comfort — even if being in international waters was within the legal realm of international law.

For her transit to Pearl Harbor, Cheyenne was given a small loadout of torpedoes. The full capability of her torpedo room was twenty-six weapons, including four in the torpedo tubes, consisting of a combination of Mk 48 torpedoes, Tomahawk cruise missiles (land-attack and antiship varieties), Harpoon antiship missiles, and sometimes, though rarely, Mk 67 submarine-launched mobile mines. However, for this transit, Cheyenne was given only 12 Mk 48 ADCAP torpedoes. With a top speed of over fifty knots while running deep, and a range in excess of 30,000 yards, the Mk 48 ADCAP was arguably the best heavy torpedo in existence. Its only real competition came from the British Spearfish, which was carried by the submarines of the Royal Navy.

The Mk 48 ADCAP, which stood for Advanced Capability, was a heavy wire-guided torpedo weighing over 3,000 pounds. Nearly 20 percent of its weight, or 650 pounds, consisted of PBXN-103 high explosive. One of the advantages of the Mk 48 was that it could be used against both submarine and surface targets, which made it much easier on logistics. It also pleased many submarine captains who still preferred the thrill of launching a torpedo over the newer, vertical launch Tomahawks or encapsulated Harpoon missiles.

Each Mk 48 was wire guided so that targeting data during the initial stages of the torpedo launch could be transmitted back and forth from the Mk 48 to the BSY-1 fire-control system on board the attack submarine. During the terminal stages of the attack, the Mk 48 would use its powerful active seeker to detect, home in on, and then destroy its target. As long as the wire was intact, information from the torpedo was constantly relayed to Cheyenne until detonation.

After the meeting, Mack returned to the control room. Knowing that there might be a nuclear attack submarine in the area, he ordered that instead of running at twenty-six knots for much of the way to Pearl Harbor, as he had originally planned, Cheyenne would now slow more frequently in order to listen to her surroundings. This “sprint and drift” technique was one of the best methods of arriving at a destination quickly while also allowing the submarine’s passive sonar to search for any possible sonar contacts.

Cheyenne was now at an ordered depth of four hundred feet. At this depth, she was in her own element, that of the depths of the ocean. If necessary, she could still be reached by the relatively new, albeit slow, ELF, or extremely low frequency, band of communications. If there were a dire emergency, or a change in her orders, Cheyenne would be instructed by a short, coded ELF message to come to communications depth in order to receive important message traffic.

Running at twenty-six knots was not always quiet. The screw, known to those outside the Navy as a propeller, was working feverishly to propel the submarine at this speed. If too shallow, this created tiny air bubbles, which made a popping noise when they collapsed. This noise was known as cavitation and could give away a submarine’s presence in the area. At this moment, Mack did not care as much about his stealth capability as he did about two other concerns: locating the submarine that was lurking dangerously near the West Coast, and arriving at the Pearl Harbor Naval Submarine Base with Cheyenne intact.

All aboard Cheyenne were aware that they were making slight cavitation noise and that anyone who was close enough and quiet enough could determine their location. The frequent slowing and so-called clearing of the baffles, the normally “sonar blind” area astern of submarines, evened the score somewhat.

At 1100 on 12 August, just ten hours after leaving San Diego, the OOD ordered Cheyenne to slow to one-third. Exactly eleven minutes later the sonar room came alive as Cheyenne slowed and her course was changed toward the north.

“Tonal contact, center bearing 187 on the end-fire beam,” called one of the young sonar operators. The consoles, which looked like computer screens with green lines running through them, were often the sonar operator’s most important ally.

An instant later the sonar supervisor, who had been paying close attention to the goings-on in this important center of the submarine, called to the captain, “Conn, sonar, we have a possible submarine contact bearing 187. We’re only receiving blade rate information so far.”

Mack entered the sonar room, joining the five other men already there — including the sonar supervisor and the sonar officer. Everyone in the room knew that there was the possibility of encountering a Chinese submarine, but also knew it was highly unlikely. Chinese naval vessels rarely ventured this far away from home waters. This was especially true of the Chinese submarine fleet, which consisted largely of older-model diesel boats with just a few very noisy nuclear-powered attack submarines of the Han class.

If there was a Chinese submarine patrolling off the West Coast of the United States, however, Mack was fairly sure that it would have to be a Han class. Naval intelligence reports had repeatedly explained that only one type of submarine was capable of travelling this far from Chinese home waters and operating — without surfacing — for an extended period of time. That type was a nuclear submarine, and the only Chinese SSN currently in service was the Han class.

Captain Mackey was, as were all experienced submariners, at least slightly familiar with the Han class of submarine. In addition, when word was passed of a possible war with China, the intelligence officer assigned to SubRon 11 from SubGroup 5 had quickly prepared a brief report of what was known of the Han class in the U.S. intelligence community. According to that report, construction of the Han class had stopped after only five submarines due to extremely high internal radiation levels, and all of those were currently in service with the Chinese navy. They carried the pennant numbers 401, 402, 403, 404, and 405 painted on their sail. One of the class had, of course, been destroyed earlier that month by a U.S. SSN. Naval intelligence was still unsure which number it was, but they reported that it was probably number 402, the second of the class. They were assuming this because it had been tracked since leaving Ningbo Naval Base in China’s East Sea Fleet four days prior to the actions involving Nimitz.

The torpedo complement fitted to the Han class was reported to be a mix of the older straight-running types as well as some of the newer Russian homing varieties. According to the reports, numbers 401 and 402 carried only torpedoes, but the last three submarines of the class, numbers 403 to 405, carried the Ying Ji. Also known as the Eagle Strike, this antishipping missile was a sea skimmer and caused great concern in the eyes of naval commanders. The most recent intelligence reports stated that while these missiles could be a significant threat to warships, the submarine needed to surface in order to launch them. And submarine commanders knew all too well that a surfaced submarine was an easy target.

Unlike the USS Seawolf, Cheyenne did not have a wide aperture array, or WAA, so she would have to triangulate the position of her passive sonar contacts in order to determine their exact bearing, speed, and range. The ship maneuvers to accomplish this would have to be done very quietly, especially if the contact, now designated Master 1, was a direct-path contact. But it was a painfully slow process.

“Captain,” the sonar supervisor said, “it’s possible the submarine was tracking us but lost us when we slowed. With these convergence zones out here in deep water, it could be in excess of 75,000 yards away. My guess is that he thinks we passed him, and based on its blade rate, is running full speed in an attempt to catch up with us and regain contact.”

That was a good guess, Mack thought, but it was still just a guess. He wanted something more than that. Proceeding to the conn, he ordered the OOD to station the section fire-control tracking party so the BSY-1 computers could be used to determine the solution on the target. The OOD would maneuver the submarine in order to change the bearings received by the towed arrays.

Mack also ordered the OOD to house the TB-16 towed array and deploy the TB-23 towed-array. Unlike the 240 feet of TB-16 hydrophones, the TB-23 towed-array sonar measured over 900 feet in length, mounted nearly 100 hydrophones, and was towed at the end of a 2,600-foot cable. Then he returned to the sonar room.

“Captain, blade rate indicates Master 1’s speed is steady at eighteen knots,” reported the sonar supervisor. “We’re getting more tonals now, including one from the conformal array. She’s definitely not American. The tonals compare to those listed in the sonar intelligence manuals as unique to Chinese Han class, number 402.”

That stopped Mack. “I thought 402 was sunk by the submarine escorting Nimitz,” he said.

“So did naval intelligence,” the sonar supervisor replied. “I guess they got their numbers mixed up. Wouldn’t be the first time.”

The captain called to the OOD, “Begin retrieving the TB-23. I don’t want to get tangled up in case we have a fight on our hands.” The towed-array sonar was valuable for quietly listening to passive sonar contacts, but Mack, like many submarine captains, preferred to retrieve it before engaging in close combat with an enemy submarine.

Mack left the sonar room and went back to the conn to see how the fire-control solution was coming.

“Conn, sonar, our contact, Master 1, just stopped his shaft.”

Seven more minutes passed, Cheyenne’s sonar operators carefully monitoring the tonals from the Chinese submarine’s reactor coolant pumps. These had to be run constantly in order to avoid destroying the reactor, one of the few drawbacks of a nuclear-powered submarine. A conventional, or non-nuclear, submarine could stop dead in the water, running entirely on her battery power, and be completely silent. A nuclear submarine, however, such as Cheyenne or Han number 402, had to constantly pump reactor coolant in order to keep the reactor critical and prevent its overheating. That difference meant that it sometimes could be easier to hunt an SSN than a regular diesel boat — especially when the SSN was an old, 1970s-vintage Han with reactor plant problems.

The silence ended when the sonar supervisor called, “Conn, sonar, single active pulse from Master 1.” Moments later there was a second sonar pulse.

Mack ordered the chief of the watch to “Man battle stations torpedo,” then took the conn from the officer of the deck.

With battle stations manned, the executive officer, in his role as the fire control coordinator, reported to the captain, “Master 1 is now bearing 169, BSY-1 range is 22,000 yards. He was not in a convergence zone.”

Aboard Han 402, the Chinese commander felt as if he had little choice but to give his position away. His sonar had acquired only intermittent contact on the American submarine maneuvering in this area, and he needed to locate it in order to accomplish his mission: sink the submarine and then continue on against American merchant ships. He knew an American submarine was out there, but didn’t know where, and didn’t know it was Cheyenne. Unfortunately for him and his crew, however, he had thought that he was much closer to the Americans than his active sonar told him he was. 22,000 yards was out of torpedo range for his submarine, but not for Cheyenne’s Mk 48s.

Those two active “pings” were a calculated risk on the Chinese captain’s part. He knew his submarine was as noisy as a bull in a china shop and he suspected the Americans had been tracking him. Once he’d figured out that the American submarine had passed him he knew they could not be far off. If he waited too long, he would miss his chance to attack.

Aboard Cheyenne, Mack was trying to outguess the Chinese captain. He knew that Chinese submarines were notorious for having very poor sonar outfits, but he didn’t think they were bad enough that the captain of number 402 would have no choice but to use his active sonar, giving away his own exact location. No, Mack thought. This does make sense. If the Chinese captain knew we were tracking him, he probably had figured that we knew his location, so all he was really doing was leveling the playing field-giving away information we already had in order to learn our location as well.

What this amounted to was that the Chinese submarine had gone active on the American submarine and both submarines now had an accurate firing solution. Mack didn’t expect the Chinese captain to let this opportunity slip away. The Han was currently outside its own torpedo range, but that could change rapidly.

“Conn, sonar, the Han just started up again. It’s making turns for twenty-five knots, sounds like she’s really straining. They are closing quickly.”

Captain Mackey reversed course to minimize the range closure while he ordered tubes one and two made ready in all respects.

“Torpedo room, fire control, make tubes one and two ready in all respects and open the outer doors.”

When the outer doors were open, Mack turned back toward the Han and increased speed to full. Both submarines were headed straight for one another in an underwater game of chicken that could potentially ignite a third world war.

“Conn, sonar, we have a torpedo in the water! Type SET-53, bearing 163. It’s active, Captain.”

“Range to Master 1 is 21,000 yards,” reported the fire control coordinator.

Mack looked around his control room. There was a look of horror in the eyes of the young sailors who had not yet been in the Navy for six months.

“All stop,” he ordered.

“All stop, aye, sir,” the helmsman repeated. Seconds later he added, “Maneuvering answers all stop.”

The normal procedure for countering a torpedo was turn and run, flank speed, in the opposite direction. This was not, however, a normal situation.

The U.S. intelligence community had managed to secretly buy three of the Chinese type SET-53 homing torpedoes from the Russians in a not-so-friendly transfer of technology. From their various tests, they had determined that the maximum range of the SET-53 was five nautical miles, or 10,000 yards. Even building in a large margin of error by doubling that range to ten nautical miles, or about 20,000 yards, Mack knew that there was simply no way that the Chinese torpedo could hit Cheyenne.

It did, however, make Captain Mackey furious, and not just because this was an act of war against the United States by a Chinese submarine. More than that, this was an aggressive action against him, his submarine, and his crew.

Cheyenne was not in any immediate danger — not yet, at least. Just in case, however, the captain calmly ordered, “Rig ship for depth charge.”

The Chinese captain had put his submarine in a very bad position. The Chinese leaders, wanting to demonstrate their power to the Americans, had given Han 402 orders to attack American submarines and surface ships operating in the area. The 402’s captain was following his orders faithfully… but he didn’t believe those orders included suicide. And he knew all too well that attacking a Los Angeles class submarine was tantamount to suicide. If he could manage to get in close enough to attack Cheyenne, he would do so. If not, he would follow his orders and launch at whatever range he felt he could without getting himself killed, and then he would dive deep and hunt for American merchant ships.

When the active “pings” revealed Cheyenne’s location, the Chinese captain realized that he had given away their location much too far away to effectively attack the Americans. With their own location revealed, closing with Cheyenne would put the Han at serious risk, which meant that his only real choice was either to simply turn and run or to first shoot at the Americans and then turn and run. The first option appealed to him the most, but the second option was what his orders demanded.

The Han captain gave the command to release a single torpedo and then began turning to his right. His only plan was to make a turn to the east and get away from the now-angry American submarine.

Mack thought about that torpedo in the water and what it meant. The Han had fired upon him without provocation, which meant that China had decided to escalate. They would be starting hostilities at any moment, and all submarines would by now have been tasked by the Chinese navy to sink any American warships, merchant ships, or submarines as they exited their home ports.

All around the world, wherever Chinese vessels came in contact with American ships, there would be blood-shed. Some of them would get lucky. Some would win, and some would lose. But this particular Chinese captain had gotten unlucky when he decided to attack Cheyenne rather than a defenseless merchant vessel.

And it was too late to change his mind.

Mack immediately saw what the Han was doing. It was turning and running — in the direction of San Diego, which could only mean one thing. China was at war with the United States.

“Conn, sonar, the Chinese torpedo just settled dead in the water,” the sonar supervisor reported. “Based on run time, it didn’t even make it 6,000 yards.”

Mack nodded. The Chinese had had their turn. Now it was Cheyenne’s.

The Los Angeles class attack submarine began to pick up speed rapidly, rushing to get behind the Han. The Chinese submarine was running from them in an attempt to escape the American submarine and return to a safe haven, hiding somewhere off the West Coast, but Cheyenne wasn’t about to allow that.

The Han’s top speed was twenty-five knots; Cheyenne was doing thirty-one knots, and the range to Master 1 closed rapidly. Both commanding officers knew it would only be a matter of time before the Americans were within firing range.

Aboard the Han, the Chinese captain’s options were limited once again. He could continue to run, prolonging things for a short while longer, or he could turn and fight.

His orders were clear, and so was his choice. At his command, his submarine came around in another slow turn and bore down on Cheyenne.

It was a noble gesture, but a futile one. The Han captain was racing to get within torpedo range, knowing that the effective range of the American Mk 48 ADCAP was more than double that of his Chinese SET-53.

“Conn, sonar, two torpedoes in the water, more SET- 53s, bearing 165.”

The fire control coordinator reported the range to Master 1 as 18,000 yards.

Mack wasn’t worried. Clearly, the Chinese had done this out of desperation. They wanted to go down fighting, and their only hope was to get lucky — and a torpedo in the water was a chance to get lucky; a torpedo unlaunched was nothing.

Cheyenne had closed to within striking range, but Mack didn’t give the orders to shoot yet. There were still two chances for the Chinese to get lucky, if those SET-53s really had a range of 20,000 yards. Captain Mackey once again gave the orders to prepare for a possible torpedo hit, and also to take evasive action by launching two ADC (Acoustic Device Countermeasure) Mk 2 decoys.

The decoys, which were launched out of what were in effect mini-torpedo tubes, accomplished exactly what they were intended to do and decoyed the torpedoes in a direction other than that of Cheyenne. The Chinese torpedoes ran out the length of their course without hitting anything solid. Their momentum spent, they settled to the ocean floor, taking Han 402’s hopes with them.

Though Mack had trained nearly his entire career for firing on an enemy submarine, he had never really expected it to happen. But Mack, like the others aboard Cheyenne, was a professional. He was calm as he gave the command, “Firing point procedures, Master 1, tubes one and two.”

A BSY-1 operator reported the relevant target data to the captain.

“Match sonar bearings and shoot, tubes one and two,” Mack said, his voice cool and steady.

“Match sonar bearings and shoot, tubes one and two, aye,” the fire control coordinator repeated the command.

The Mk 48s were launched from the weapons control console and were ejected from their tubes. Their Otto fuel engines came to life, powering their pump jets.

“Tubes one and two fired electrically,” said the combat systems officer at the weapons control console.

As soon as the torpedoes entered the water, the Chinese submarine began to turn. Mack guessed that they were going to try a ninety-degree turn away from the Mk 48s, but the seeker heads on the ADCAPs were doing what they had been designed to do: hunt down an enemy submarine. They stayed with the Han as it twisted and turned.

“Both torpedoes have acquired Master 1,” reported the combat systems officer. Both Mk 48s had found the enemy submarine with their own sonars and no longer needed to be guided by Cheyenne’s fire-control system via their guidance wires.

“Cut the wires, shut the outer doors, and reload tubes one and two,” ordered Captain Mackey.

“Conn, sonar, two explosions, bearing 162.”

A cheer erupted in the control room, but Captain Bartholomew Mackey did not join in. The sailors were celebrating the fact that Cheyenne had just achieved her first blood, but Mack knew that more than that had just happened.

War with mainland China was now a fact of life.

A short time later, Mack secured from battle stations and ordered Cheyenne to proceed to periscope depth. Using SSIXS (Submarine Satellite Information Exchange System), Mack communicated their actions to the higher-ups in the Department of Defense and the Navy. As Mack had suspected, message traffic indicated that their encounter had not been an isolated incident and Cheyenne soon learned that what seemed like an all-out war had been started by China in an attempt to assert its position in the new world order.

Cheyenne’s orders were again confirmed and she was to remain on course, sprinting and drifting until arriving at Pearl Harbor so that she could resupply and join other American units in the South China Sea. There was one important change in her orders, however: she was now allowed to attack any Chinese naval vessel she encountered so long as her trip to Pearl would not be overly delayed.

The remainder of the trip to Pearl was a tense one. Every moment that passed increased the likelihood that they would once again face combat. Running at four hundred feet toward the submarine safety lanes southwest of the Big Island of Hawaii, the OOD brought the submarine shallow to copy over the floating wire any news that might have occurred since their last venture toward the surface. The news was not good.

Two Spruance class destroyers, the USS Fletcher (DD 992) and the USS John Young (DD 973), were operating in conjunction with the Coast Guard cutter Midgett (WHEC 726). One of the SH-60 Seahawks from Fletcher had dropped a line of sonobuoys about 150 miles south of Honolulu and detected a possible sonar contact. All vessels had been told of the friendly submarine traffic in the area, but the contact the Fletcher’s Seahawk detected did not match any of the sonar profiles of the submarines expected to be operating nearby.

Another Seahawk from John Young was en route to the area. Its orders were to assist in determining what type of contact the sonobouys were tracking.

Cheyenne went to periscope depth. Word came to them over the periscope communications antenna, on the “Navy Red” encrypted circuit from one of the helicopters, that there was a possible enemy submarine operating in the area, which turned out to be forty-two nautical miles north of Cheyenne’s current location. The message also indicated that Cheyenne’s assistance would be greatly appreciated. Mack acknowledged the pilot’s request, and then ordered Cheyenne to return to operational depth and proceed toward the reported datum.

Forty-seven minutes later Cheyenne’s towed-array sonar detected the sonar contact. They were still out of range and could not tell much about the contact. They knew only that it might be a submarine, and that, if it was a submarine, it was attempting to be as quiet as possible. The sonar supervisor designated this new contact as Cheyenne’s Master 2.

On the surface, the two U.S. destroyers and the Coast Guard cutter were hunting the sonar contact. The surface ships were attempting to keep their distance from the contact, wary of a possible torpedo attack. The Seahawks did not have to worry about that, and at 1340, moments after the surface ships had confirmed that the contact was indeed another Chinese nuclear submarine, Cheyenne heard the sounds of two Mk 50 torpedoes entering the water.

“Conn, sonar, torpedoes in the water… Mk 50s, bearing 017. The Seahawks just dropped weapons on the submarine contact, Master 2.”

A short time later the small helicopter torpedoes went active. Cheyenne heard two noisemaker decoys being launched, followed by the loud cavitation of the Chinese submarine as it attempted to outrun the Mk 50s — to no avail.

“Conn, sonar, two explosions, bearing 023.”

“Radio, Captain,” Mack said. “Send congrats to the helo pilots over Navy Red; they just sank themselves an enemy submarine!”

Cheyenne’s crew was justifiably jubilant at having witnessed the destruction of a second Chinese submarine. Perhaps it had not been as exciting as their initial taste of combat, but it had boosted their confidence in their naval brethren hundreds of feet above them.

More than that, though, they were buoyed by the fact that every aspect of their first mission had gone off without a hitch. Mack ordered Cheyenne to proceed to Pearl. Once there, they would complete their mini-refit and prepare Cheyenne for her next operation: her transit to the home waters off China — the South China Sea.