Ssn (1996)

by Clancy, Tom

  So far, there was no need for TLAM-N, which would be a waste on the relatively tiny islands. Besides, the digital terrain data of the Chinese mainland itself, which met the Tomahawk TERCOM and DSMAC data requirements, more fully supported TLAM-N. Unlike the Spratlys, data on the mainland had been accumulated and processed years earlier, in less of a rush, against the possibility of future U.S. nuclear bomb attacks on China.

  The briefing was professional and highly detailed. Mack came away with all his questions answered, and a clear sense of Cheyenne‘s mission. But no briefing was ever absolutely complete. The briefing officer could not pass along information he didn’t have, and on the last day of Cheyenne’s refit naval intelligence had not discovered—or, as sometimes happened, had somehow neglected to pass on—the fact that there was a new player in the area. The Chinese already had a large fleet of submarines purchased from the economically ailing Russians, and that fleet had just gotten bigger. The Chinese had recently acquired a Russian Alfa class SSN, and the Alfa was now on patrol in the South China Sea.

  Mack didn’t know about the Alfa yet, but he did know that his submarine and his crew were ready for anything the Chinese cared to throw at them, though with the sheer numbers of assets the Chinese had hunting them, Cheyenne would have to be cautious. The Chinese had the advantage of being used to dealing en masse; Cheyenne had the advantage that their enemy obviously had no coordination of surface and subsurface forces—something Mack had noted in his previous encounters.

  After the briefing, Mack’s officers went back to Cheyenne to get her ready for departure. Mack stayed behind for a little while longer.

  Mack met with the McKee captain and CTF 74 in the admiral’s sea cabin. Cheyenne was facing the possibility of shallow water operations, and her crew needed to prepare for that. Shallow water operations were difficult and dangerous, and there had simply been no opportunity to practice before Cheyenne was ordered to ready herself for deployment.

  In the admiral’s sea cabin, Mack reported to the other two officers that after departure, Cheyenne’s crew would practice shallow water, high speed maneuvering, and shallow water towed-array operations first. That way, if the TB-16 array were to touch bottom before their proficiency had peaked, the soft bottom of the Sulu Sea would ensure that the array would be undamaged. Mack needed to ensure that his diving officers, helmsmen, and planes-men were ready so that they would not overreact during high speed, shallow water maneuvers, and either broach the ship or drag the propeller and lower rudder through the bottom. Mack knew that it didn’t take much angle for a 360-foot submarine in 20 fathoms of water to subject itself to the dangers of the surface or the ocean bottom.

  In addition, Mack requested and received permission to use the McKee captain’s gig in their exercises. This would provide an adequate surface target for active sonar detection and tracking in the irregular contours and the varying wind driven thermal gradients. Mack would use the gig to practice active sonar tracking with the BSY-1 spherical array at low power and short pulse lengths and with the higher-frequency MIDAS under-ice and mine-hunting sonar as they approached the Balabac Strait south of Palawan.

  Cheyenne would have to wait for the rocky bottom and shoals off Cuarteron Reef to once again be their proving grounds should the Chinese submarines decide not to venture forth into deep water. The Captain hoped MIDAS would be able to distinguish between the coral reefs and the anechoic coatings of the Chinese submarines. But then, active sonar would be used only if Cheyenne’s presence were otherwise known.

  There was one other point Mack had to bring up. He liked to assume that the Chinese had equivalent overhead satellite imagery capability, and he was concerned for McKee’s safety.

  The admiral advised him not to worry, however, since they intended to weigh anchor shortly after Cheyenne’s departure and would periodically relocate outside the Chinese intelligence satellites’ footprints. The actual location of the next rendezvous would be provided to Cheyenne as soon as it was decided upon. It might even be in port in Brunei, or off that coast, where carrier air protection could be afforded both McKee and Cheyenne during their next reload period.

  Mack was pleased to hear that—and doubly pleased to know that chances for another reload were good—but he also knew that it would only be true if he could keep the Chinese submarines away from the basically defenseless McKee before the Independence Battle Group arrived to relieve him of the burden of protecting the tender.

  Shortly after getting under way from alongside McKee, Cheyenne quietly submerged. They weren’t scheduled to come to the surface again for quite some time—and, depending on how much action they saw and how well they fared in Cheyenne’s next war patrol off Cuarteron Reef, it might be even longer before they saw McKee again.

  As he had briefed his admiral, Mack made sure that they practiced the shallow water, high speed maneuvering en route. This maneuvering was not unlike flying an airplane—even some of the terminology was similar. In deep water, where the automatic depth-control system would frequently be used, the submarine’s vertical position in the water column was referred to as “depth.” During these maneuvers, however, the term was “altitude,” with added emphasis on maintaining a comfortable safety margin or altitude in the water column above the ocean bottom. To help with this, the upward-looking beams of the under-ice sonar, MIDAS, continually displayed the distance to the surface, while the secure fathometer, with its narrow sonar beam, provided the altitude information.

  As Mack had hoped, the McKee captain’s gig turned out to be a useful target for active sonar tracking. In addition, it provided a source of sonar passive tonal information. In shallow water like this, the TB-16 towed array’s entire 2,600-foot tow cable, with its 240 feet of hydrophones at the end, could not be totally deployed. Instead, it would be deployed at a “short stay,” an optimum length for all hydrophones to be at some distance away from its own ship tonals, yet short enough to ensure that it remained off the bottom during maneuvers, its own “towed-array altitude.”

  The longer TB-23 thin-line array, with its 960 feet of hydrophones, would remain stowed for these war patrol shallow water operations, thus ensuring its availability for deepwater tracking operations when—and if—the Chinese ventured into the deeper waters of the South China Sea. The depths northwest of the Spratly Islands, ranging to over 15,000 feet, were ideal for convergence zone tracking of the noisy Chinese submarines while they were running at high speeds.

  Cheyenne had nearly completed her exercises when Mack heard over the speaker at the periscope stand, “Captain, radio, incoming flash traffic!”

  Proceeding quickly to the radio room, he arrived in time to see the printer spitting out new orders. Cheyenne was to proceed at best speed to a location west of Cuarteron Reef. Overhead imagery had shown that the Chinese were stirring, probably preparing to deploy under cover of darkness, which was only hours away.

  Mack was ready. Before beginning the high speed, shallow water maneuvers, he had decided that Cheyenne should not dally inside the Sulu Sea. Instead, he had decided to continue west while conducting the proficiency training, and now he was doubly glad that he had made that decision.

  Cheyenne had earlier released the captain’s gig to return to McKee. Now, having already cleared Balabac Strait, deep water was nearby, so the captain used the radiomen’s microphone to pass the order, “Officer of the deck, Captain, shift main coolant pumps to fast speed and then proceed to flank speed. Make your depth four hundred feet.”

  The OOD repeated the captain’s order verbatim, then ordered maneuvering to shift the main coolant pumps to fast speed. The OOD could have accomplished the same thing by ordering flank on the engine order telegraph, a “jump bell,” but that method, which was faster than ordering maneuvering to shift the coolant pumps, was saved for when speed was of the essence ... as in torpedo evasion.

  Cheyenne arrived northwest of West Reef shortly after nightfall, remaining outside the 100 fathom curve for the time being. Upon receiv
ing the report from the officer of the deck that they were on station, Mack proceeded to the control room.

  “Make preparations to come to periscope depth,” he said.

  After acknowledging the captain’s order, the OOD slowed to two thirds and brought Cheyenne up to 130 feet, above the layer, and cleared baffles. He then advised the captain that he had no sonar contacts and was ready to proceed to periscope depth.

  “Very well,” Mack replied. “Come to periscope depth.”

  “Come to periscope depth, aye, sir. Sonar, radio, conn, proceeding to periscope depth.”

  “Conn, sonar, aye. No contacts,” replied the sonar supervisor.

  “Conn, radio, aye ... manned and ready.” That acknowledgment came from the communicator.

  “Diving officer, make your depth six zero feet smartly,” ordered the OOD as he raised the Type 18 periscope and started his underwater visual sweeps to make sure there were no dead-in-the-water underwater hulls for Cheyenne to run into during this last, most tenuous part of the trip to periscope depth.

  “Make my depth six zero feet, smartly,” answered the diving officer. “Smartly” meant that the diving officer would maintain the two-thirds bell as he ordered the helmsman to fifteen rise on the bow planes and ordered the planesman to a fifteen degree up bubble. Using the stern planes to control Cheyenne’s angle, the bubble would be eased as Cheyenne was nearing eighty feet for the final glide to sixty feet.

  “Seven zero, six five, six four, six three, six two,” the diving officer said, counting down their depths.

  When the count hit six two, the OOD called out, “Braking,” and quickly swung the periscope through a 360-degree arc. A moment later he said, “No visual contacts, Captain.” There were a number of radar contacts chirping over the Type 18 ESM receiver, but the periscope wasn’t picking up any visuals.

  “Ahead one third,” Mack ordered quietly to the OOD, not wanting to be entered in the deck log as having assumed the conn.

  “Conn, ESM, I have five ESM contacts, one a Chinese radar, and four Russian radars. HULTEC indicates a Han class, three Kilo class, and one Alfa class. The closest is the Han at signal strength three and increasing.”

  Captain Mackey and the OOD looked at each other with surprise.

  Mack turned to the microphone. “ESM, Captain,” he said, “are you sure about that Alfa?”

  “Yes, sir, Captain,” answered the voice of the NSG OIC. “It’s an Alfa. We’ve seen him, this particular one, in the North Fleet numerous times. No mistaking it, sir. He’s well registered in our computer database.”

  “Executive officer,” spoke the captain calmly as he turned to the executive officer standing aft in the darkness of the rig for black. “Are you back there?”

  “Yes, Captain. Should I draft a message report on the Alfa?”

  “Please do so. Release it when ready. We need to find out what gives.” The Alfa was designated Master 31, the Han Master 32, and the three Kilos Masters 33, 34, and 35.

  In less than half an hour, Cheyenne’s flash message report had been sent and answered by the communicators at CTF 74 headquarters in Yokosuka.

  Mack read the CTF message and filled in his executive officer on what he’d learned. “ESM is right. It seems the ’friendly’ Russians have sold a North Fleet Alfa to the Chinese,” he said, “who then crewed it and overhauled it, apparently at Cuarteron Reef. How many more Alfas are being transferred to China is anybody’s guess at this time. Naval intelligence is working on the problem. They’re paying special attention to the recent lack of openness of the Russian submarine bases at Vladivostok and Petropavlosk.”

  Mack chose this method of informing his executive officer, rather than filling him in during a private briefing, because he’d made a policy of ensuring that all his crewmen were knowledgeable about any enemy they were likely to encounter.

  Because of this, the messenger of the watch—who had heard the initial ESM report but not the follow up—knew, or thought he knew, the implication of an Alfa, a Russian submarine, in the immediate area. The messenger of the watch quickly spread the word through the crew’s mess as he stood there with his red goggles on, drawing coffee for the control room watch standers. The movie operator even shut down the movie and turned on the lights so they could all discuss the new information.

  But for all Mack’s openness, the crew was never as well informed as the officers. In this case, because the messenger of the watch had been sent for coffee before hearing Mack’s final report, none of the crew on board Cheyenne knew that the Alfa was manned not by Russians but by Chinese sailors.

  The captain called for an immediate meeting of all officers in the wardroom to share with them the new intelligence on the Alfa, manned by Chinese, and its current exodus with a Han and three Kilo SSKs. He expected the SSNs to wait for deep water before diving, but anticipated the Kilos would dive in twenty fathoms.

  That was as far as Mack got before the OOD called him on the sound-powered phones, allowing the mess specialist to sneak out of the wardroom galley and pass the word on the Chinese crew to the already buzzing crew’s mess.

  “Captain, ESM reports the Kilo radars and the Han radar have shut down. They were drawing left while the Alfa radar is still drawing right.”

  “Okay, men. We have our work cut out for us. The three Kilos and the Han have probably submerged. And the Alfa may be trying to do an end around to get behind us. It’s time to man battle stations.”

  Mack’s reading of the situation was correct. Sonar had just finished reporting tonals from the Han SSN to the conn as the captain arrived and ordered the OOD to man battle stations torpedo. There was still nothing from the Kilos acoustically, but the Alfa had also shut down its radar—last bearing due south of Cheyenne.

  As directed by the captain, who was now the conning officer, the executive officer, in his role as the fire control coordinator, passed the order to the torpedo room over the sound-powered phones, “Torpedo room, fire control, make tubes one and two ready in all respects, including opening the outer doors.” He wanted to get the tubes ready as early as possible and as far from the enemy submarines as possible.

  The order from the captain, carried by the open microphone at the periscope stand, alerted the sonar operators that noisy evolutions would be taking place near the BSY-1 spherical array so they could attenuate the sound level reaching their sensitive ears.

  The torpedo room crew acknowledged the order. “Make tubes one and two ready in all respects, including opening the outer doors, fire control, torpedo room, aye.”

  Moments later, the torpedo room reported completing the ordered evolution with the torpedo tubes. The executive officer relayed the information to Mack. “Captain, tubes one and two are ready in all respects. Both outer doors are open.”

  “Very well, fire control,” answered the captain.

  The Han was drawing left and closing. It was not quiet by any means, and was easily tracked by the TB-16, spherical, and conformal arrays at the same time. The inputs to the three BSY-1 computers made the solution a snap for the fire-control party.

  When the BSY-1 operator and the fire-control coordinator were satisfied with the TMA (target motion analysis) solution on Master 32, the Chinese Han class attack submarine, the captain ordered, “Firing point procedures, Master 32.”

  The combat systems officer reported the target course, speed, and range.

  “Sonar, conn, stand by,” ordered the captain.

  “Conn, sonar, standing by.”

  “Match sonar bearings and shoot, tubes one and two, Master 32.”

  “Match sonar bearings and shoot, tubes one and two, Master 32, aye.”

  After the large piston of the torpedo-ejection pump ram drove home, the Mk 48 ADCAP torpedoes were ejected from their resting places at the same time that their Otto fuel engines were coming up to full speed. “Tubes one and two fired electrically,” reported the combat systems officer.

  “Conn, sonar, units from tubes one and two running
hot, straight, and normal,” came the report from the sonar supervisor as the two torpedoes executed their wire clearance maneuvers and accelerated rapidly to fifty knots en route to convergence with the Chinese submarine.

  “Very well, sonar,” Mack said. Then, a moment later, he asked, “Time to acquisition?”

  “Eight minutes, Captain,” answered the combat systems officer.

  To Mack, it seemed like an eternity before he heard, “Unit one has acquired ... Unit two has acquired.”

  “Cut the wires, shut the outer doors, and reload tubes one and two,” Mack ordered now that the Chinese submarine’s fate was in the hands of the Mk 48s. There was no escaping their relentless attack. The subsequent reverberations and breaking up sounds were deafening.

  “Conn, sonar, we have a torpedo in the water, SET-53, bearing 089!” The sonar supervisor’s excited report came just as the ocean started to quiet. Apparently the Han CO had launched a snap shot at the bearing of the incoming torpedoes as part of a last-ditch effort prior to his certain death.

  “Right full rudder, all ahead flank. Cavitate. Make your depth one thousand feet,” Mack said, followed rapidly by his calm, but forceful words over Cheyenne’s 1MC, “Rig ship for depth charge.”

  With the ship already at battle stations, the reports from Cheyenne’s various compartments came in quickly to the chief of the watch at the ballast control panel. The engineering officer of the watch (EOOW) had ordered main coolant pumps shifted to fast speed, and the throttle man answered the ordered bell as soon as the pumps were reported in fast speed by the reactor operator.

  In fact, the throttle man was a little quicker than the EOOW had expected. With the precision of his training, he had acknowledged the engine order telegraph backup to the captain’s orders and was already nearing 50 percent steam flow. Now he was just waiting for the chance to complete his spinning open the main engine throttles, which he couldn’t do until the steam generator automatic level controls allowed him to. The safeguards were there to prevent excessive level swell, which might result in carry-over of water into the steam piping.