A second order had subsequently been received, sending Michigan southeast. Now, an hour after the northeastern turn at the bottom of the gulf, Wilson’s crew was approaching its destination — the minefield stretching across the Strait of Hormuz. Although Michigan’s slower speed had been a handicap earlier, the guided missile submarine’s new capabilities might now come in handy. It would take over a week for mine-clearing assets capable of dealing with the deeper mines to arrive at the strait. In the meantime, Wilson had been ordered to devise a way to utilize the SEAL detachment and their equipment aboard to clear a path through the minefield.
Wilson glanced at the navigation display; Michigan was fifteen nautical miles from the strait, still traveling at ahead full, with the turbulent water flowing past the hydrophones blunting the detection range of the submarine’s sensors.
“Slow to ahead two-thirds,” Wilson ordered Lieutenant Brian Resor, the Officer of the Deck.
Resor relayed the order to the Helm, slowing the ship to ten knots. He followed up, “Sonar, Conn. Report all contacts.”
Two minutes later, after shifting their equipment lineup to take advantage of the longer detection range of the submarine’s sensors at the slower speed, Sonar reported, “Hold a new contact on the towed array, designated Sierra eight-five, ambiguous bearings zero-zero-five and zero-nine-five.”
With the towed array being a single string of cylindrical hydrophones, the sonar algorithms couldn’t determine which side of the array the sound had been received on. A maneuver would be required to determine whether the contact was to the north or east. More important, however, was the contact’s classification — surface ship or submarine. Sonar quickly completed its initial assessment.
“Conn, Sonar. Sierra eight-five is classified submerged. Analyzing.”
No other American or NATO submarines were authorized in Michigan’s new operating area, which meant Sierra eight-five wasn’t friendly.
Wilson turned to his Officer of the Deck. “Man Battle Stations Torpedo silently.”
55
K-328 LEOPARD
Captain Second Rank Maksim Sidorov, seated in the Captain’s chair in the submarine’s Central Command Post, listened intently to Hydroacoustic’s report.
“Command Post, Hydroacoustic. Hold a new contact on the towed array, a sixty-point-two Hertz tonal, designated Hydroacoustic two-five, ambiguous bearings one-one-zero and two-five-zero. Sixty-point-two Hertz frequency correlates to American nuclear-powered submarine.”
Interesting, Sidorov thought.
The commanding officer of Leopard, a second flight Akula nuclear attack submarine, and his crew had waited patiently at their assigned station just west of the minefield stretching across the Strait of Hormuz. The explosive barrier had done its job thus far, preventing additional American warships from entering the Persian Gulf to assist the Theodore Roosevelt strike group, helping to ensure that the preeminent symbol of U.S. naval power — the potent aircraft carrier — did not escape its doomed fate.
Sidorov’s assignment was less glamorous than that of the other four Russian submarines hunting the aircraft carrier. Leopard’s task was to assist in keeping the minefield in place, sinking mine-clearing ships that attempted to clear the obstacles. What he hadn’t expected was the arrival of the lone American submarine in the gulf. Why was it headed toward the strait instead of protecting the aircraft carrier?
The next report Sidorov received was even more perplexing. “Command Post, Hydroacoustic. Contact tonals correlate to American ballistic missile submarine, Ohio class.”
The report confused Sidorov. What was a ballistic missile submarine doing in the Persian Gulf? They normally prowled the depths of the Atlantic and Pacific Oceans, far away from the busy shipping lanes, hiding during their months-long patrols. Then he realized the new contact wasn’t a ballistic missile submarine at all. It was one of America’s four guided missile submarines — Ohio-class submarines converted to carry Tomahawk missiles and a SEAL detachment.
During the recent engagement with the Theodore Roosevelt strike group, two submarine escorts had been detected. The lead submarine had been sunk, but the second had faded from the sensor screens as it accompanied the evading aircraft carrier. That submarine had now been located, approaching the strait for some reason. The American submarine’s mission was unclear, but its fate was not.
“Man Combat Stations silently,” he ordered.
The two Command Post Messengers sped through the submarine, and three minutes later, Leopard’s Central Command Post was fully manned.
“This is the Captain,” Sidorov announced, capturing the attention of the Command Post watchstanders. “I have the Conn and Captain Lieutenant Yegorov retains the Watch. The target of interest is Hydroacoustic two-five, an American guided missile submarine. Track Hydroacoustic two-five.”
As his crew set to their initial task — determining their target’s course, speed, and range — Sidorov knew he had the advantage over his adversary, even if Leopard had been detected.
The contact had been gained on the towed array, but even though two ambiguous bearings had been reported, Sidorov already knew which one was the true one and which one was false. With the minefield barrier on Leopard’s starboard side, the approaching American submarine was clearly to port, bearing two-five-zero. No maneuver would be required to resolve the bearing ambiguity.
Additionally, Sidorov’s crew already had a rough target course to work with, since the Persian Gulf slanted northeast as it met the Strait of Hormuz. It would not take long to lock down a firing solution for the approaching American submarine. A single maneuver should provide Leopard’s fire control algorithms with the information necessary.
Sidorov ordered, “Steersman. Ahead standard. Left full rudder, steady course one-nine-zero.”
56
USS MICHIGAN K-328 LEOPARD
“Conn, Sonar. Master one is classified Akula.”
Wilson acknowledged Sonar’s report, then surveyed the watchstanders in the Control Room. Michigan was at Battle Stations Torpedo, every station manned with his crew communicating via headsets, augmented by occasional reports from Sonar coming across the Conn speaker. The submarine’s Executive Officer, Lieutenant Commander Tom Montgomery, hovered behind the three combat control consoles, examining their displays.
The console operators — two fire control technicians and one junior officer — adjusted Master one’s estimated solution: its course, speed, and range, analyzing how the combat control system reacted. It was a complicated process combining complex algorithms and the operator’s ability to fuse the myriad data available — frequency shifts and bearing changes over time, geographic constraints, and target characteristics — using the data to guide the algorithms more quickly to an accurate target solution.
Montgomery stood erect, alerted by a report coming across his headset. After acknowledging, he announced, “Possible contact zig, Master one, due to upshift in frequency.”
Wilson glanced at the nearest time-frequency plot. The target’s tonals were increasing. He checked the contact’s bearing drift; the bearings were drifting to the left of those projected by combat control, indicating a maneuver to port.
Montgomery’s eyes shifted between the combat control displays, coming to the same conclusion. “Confirm target zig. Contact has turned to port. Set anchor range at ten thousand yards. Master one has turned to a southern course and has increased speed.”