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.