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, TKVW 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-23.1 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 white 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
