Livingston repeated back the order and issued commands to his watch section. After settling in behind Yury Dolgoruky, Tolbert had returned North Dakota to a normal watch section rotation, with each watch augmented with a Section Tracking Party comprised of an additional fire control technician to monitor the plots, a Contact Manager, and a Junior Officer of the Deck. By setting the Arctic Routine, Tolbert had ordered additional sonar consoles manned and the Deck and Conn split, with Tolbert and the XO alternating as the Conning Officer.
After a briefing from the Weps, Tolbert relieved him of the Conn, announcing to watchstanders in Control, “The Captain has the Conn, Lieutenant Livingston retains the Deck.”
The Quartermaster acknowledged and continued preparations for entering the Marginal Ice Zone. He energized the submarine’s topsounder and fathometer. The topsounder would send sonar pings up from one of four hydrophones mounted on top of North Dakota’s hulclass="underline" two on the sail and one each on the bow and stern. The topsounder would detect ice above and provide warning if an ice keel descended toward them. To help avoid the occasional small iceberg, North Dakota would run deep, closer to the bottom than usual, using the fathometer to ensure they didn’t run aground.
One of the sonar watchstanders shifted consoles, preparing to energize North Dakota’s High Frequency Array, the forward-looking under-ice sonar mounted in the front of the sail, which would detect ice formations ahead. The sonar technician entered the requisite commands, bringing the console on-line, then cast furtive glances toward the ship’s Captain.
Tolbert knew what he was thinking. North Dakota’s topsounder and fathometer weren’t detectable, emitting narrow high-frequency beams that bounced back to North Dakota after reflecting off the ocean’s surface or bottom. That was not the case with the High Frequency Array, which sent pulses out in front of the submarine. Having set the Arctic Routine, Tolbert had to make the decision he’d been putting off — whether to energize the under-ice sonar and risk being detected.
Commander Tolbert announced his decision. “Attention in Control. We will not use our under-ice sonar. We’ll let the Russians pick a path through the Marginal Ice Zone, and follow directly behind. Carry on.”
Tolbert added, “Pilot, come to course three-five-five.”
The Pilot entered the new course and North Dakota turned slightly left. Tolbert had been trailing the Russian submarine with an offset to starboard, but needed to trail directly behind while in the Marginal Ice Zone.
After North Dakota eased into position behind the Russian submarine, Tolbert turned back to the north. Moments later, the Quartermaster looked up from the electronic chart and announced, “Entering the Marginal Ice Zone.”
7
Yury Dolgoruky continued her steady trek north at ten knots. Thus far, the topsounder had detected only sporadic chunks of sea ice floating above them, while the bottomsounder reported the smooth, shallow bottom of the Barents Sea, averaging only 230 meters in depth. However, Stepanov was focused on Dolgoruky’s Ice-Detection Sonar display, which displayed objects in front of them as a colored blotch. Different colors represented the intensity of the sonar return, with red indicating a large, deep, or dense formation.
Unfortunately, ice-detection sonars were not very good at determining the depth of the object, which is what ultimately mattered. The color of the ice was key. As Dolgoruky closed on the object, shallow ice keels would recede upward and exit the top of the ice-detection beam. As it receded, the color would change from bright red to darker, cooler colors until it faded to black.
The Ice-Detection Sonar used a simple geometry algorithm to determine if the obstacle was a threat. If the ice didn’t change from red to another color within a certain distance — the Minimum Allowable Fade Range — Stepanov would have to turn or go deeper. The display was black; there were no ice formations ahead.
Several hours after entering the Marginal Ice Zone, Stepanov approached his First Officer.
“If an American submarine is following us, where are they?” Stepanov asked.
Pavlov answered, “They are directly behind us.”
“Why?”
Pavlov replied, “They are not using their under-ice sonar, afraid we will detect it. They are using us to chart a safe path through the Marginal Ice Zone.”
“Correct,” Stepanov replied. “That is what I needed to determine.”
When Stepanov did not amplify, Pavlov asked. “What is your plan?”
Stepanov replied, “We will use their lack of under-ice sonar against them.”
“How do we do that?”
Stepanov smiled. “We continue north, under the polar ice cap.”
As North Dakota continued north, Tolbert stopped by the navigation plot, examining the multicolored curves on the display. They were midway through the Marginal Ice Zone, passing between the archipelagos of Svalbard to the west and Franz Josef Land to the east. If Dolgoruky held her northern course, she would slip beneath the polar ice cap in a few hours.
“XO.” Tolbert summoned his Executive Officer, who joined him at the navigation plot. “Draft a message to CTF-69, advising them we’re tracking Yury Dolgoruky and might proceed under the polar ice cap.”
Lieutenant Commander Sites acknowledged and headed into Radio. The message was quickly drafted and Tolbert reviewed it, releasing it for transmission.
“Officer of the Deck, prepare to proceed to periscope depth. We have one outgoing.”
8
Seated at her desk in her West Wing office, National Security Advisor Christine O’Connor looked up from her computer display. Through her windows, she could see the Eisenhower Executive Office Building. Called the wedding cake by some due to its layered, palatial facade, the building housed the vice president’s ceremonial office. A heavy snow had started falling this morning, and a thick blanket was already coating the ornate building.
The white landscape reminded Christine of the scenery around Moscow, which pulled her thoughts back to the document on her computer monitor; her report on nuclear arms reduction negotiations between the United States and Russia. The report detailed the agreements reached to date, the differences to be resolved, and the one issue Russia was unwilling to negotiate. She had her suspicions as to why, which she would lay out during her 9 a.m. meeting with the president.
Her thoughts were interrupted by a firm knock on her door. “Enter,” she said, and the door opened, revealing a Naval officer in dress blues, with four gold stripes on each sleeve.
Captain Steve Brackman was the president’s senior military aide. There was no one on the president’s staff she had worked more closely with, agreeing on almost every issue. When engaging in battle with other staff over national security issues, it helped having the military on her side. A few months ago, when Brackman approached the end of his two-year tour, she had talked him into extending, not wanting to risk dealing with a replacement with opposing viewpoints.
“Good morning, Christine. The president’s schedule has changed and he’d like to meet with us now.”