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 — Wilson would have to turn or go deeper. The display was black; there were no ice formations ahead.
Their journey beneath the ice would be treacherous, transiting over the shallow Chukchi Shelf in the Pacific and the Barents Shelf in the Atlantic. The ice keels were still deep this time of year, leaving little room for safe transit. As Wilson prepared to take Michigan beneath the ice, he knew he wouldn’t get much sleep until they reached the deep-water basins of the Arctic Ocean.
The Quartermaster looked up from the electronic chart and announced, “Entering the Marginal Ice Zone.”
Four days later, with his submarine five hundred feet beneath the polar ice cap, Captain Wilson entered USS Michigan’s Control Room, stopping to examine the electronic chart, assessing his submarine’s transit. Michigan was traversing the deep-water portion of the Arctic Ocean, her main engines pushing the eighteen-thousand-ton submarine forward at ahead flank speed. They were approaching the Lomonosov mid-ocean ridge, which rose rapidly to three thousand feet before dropping off to an average depth of fourteen thousand feet. In the deep-water basins, Michigan could proceed at maximum speed without fear of hitting the bottom or ice keels descending from above.
Beside Wilson stood Petty Officer Second Class Pat Leenstra, on watch as Quartermaster. Leenstra was analyzing the ship’s two inertial navigators for error. Once Michigan passed 84 degrees north latitude, both inertial navigators had been shifted to Polar Mode to compensate for the reduced effect of the earth’s rotation. Traveling across the top of the world was always touchy when relying on inertial navigators. For example, when at the North Pole, no matter which direction you turned, you were headed south.
“How are we doing, Leenstra?”
“Good, sir. Both inertial navigators are tracking closely together.”
That was good news, as they wouldn’t be able to get a satellite fix until they exited from under the polar ice cap, or came across a lead or polynya. The ice cap was not a solid sheet of ice, but a piecemeal collection of ice floes jammed together by the wind, currents, and waves. The floe edges did not always meet, creating leads — narrow gaps within which submarines could surface. There were also polynyas — ice-free holes the size of a small lake, often large enough for two or more submarines to surface. Polynyas were rare, however, with submarines almost always surfacing in leads or punching through a thin section of ice.
The under-ice transit had been uneventful thus far, and it wouldn’t be long before Michigan entered the Barents Sea.
Several days later, Michigan prepared to exit from under the ice in the Barents Sea.
“Approaching the Barents Shelf,” the Quartermaster announced.
“Helm, ahead two-thirds,” Wilson ordered, stationed as the Conning Officer again.
Wilson slowed from ahead flank as they approached the Barents Shelf, where the bottom rose rapidly from a depth of fourteen thousand feet to less than seven hundred. In another hour, they’d exit from beneath the polar ice cap and enter the Marginal Ice Zone again, then continue their trek south toward the Russian torpedo.
CHAPTER 6
GADZHIYEVO, RUSSIA
Along the curving shoreline of Yagelnaya Bay, with the early morning sun cresting the rocky hills to the east, Captain Second Rank Anatoly Mikhailov strode down the pier toward his submarine. The six-week-long polar night had ended a few months ago and the snowfall had ceased, but his shoes still crunched through the white remnants of the Kola Peninsula’s harsh winter. Tied up alongside the center pier of Gadzhiyevo Naval Base were Russia’s two newest nuclear attack submarines: K-561 Kazan and K-562 Alexander. The Yasen class submarines incorporated cutting-edge technology and were formidable ships. Mikhailov hoped an opportunity would soon arise to test his submarine’s capabilities against his American counterparts.
The sun glinted off the sides of his 140-meter-long submarine, the white uniforms of his men assembled topside contrasting with the ship’s black hull. All appeared ready for Kazan’s sortie to sea this morning. Across the pier, Alexander’s crew was also preparing to get underway. They had disconnected from electrical power and other shore services, and its brow was being lifted away by the nearby crane, swinging it onto the pier.
Mikhailov crossed the brow onto his submarine as the crane swiveled around toward Kazan. After exiting the Murmansk Fjord and entering the Barents Sea, both submarines would return to the same operating area where they had tested the torpedo last week. Technical adjustments had been made, Mikhailov had been told, although the design leads were tight-lipped about what those changes had been. He looked forward to a successful test, with Kazan’s role appropriately recognized.
Mikhailov stopped beside his First Officer, standing before the crew formation. After an update on preparations this morning and satisfied that his submarine was ready, Mikhailov gave the order.
“Station the underway watch.”
CHAPTER 7
USS MICHIGAN
“Two nautical miles to the mark,” the Quartermaster reported.
Now that Michigan had exited from under the polar ice cap and left the Marginal Ice Zone behind, Wilson had resumed the submarine’s normal underway watch stations. Lieutenant Bradley, on watch as Officer of the Deck, ordered Michigan to slow.
“Helm, ahead one-third.”
Michigan slowed to five knots and Bradley joined Captain Wilson at the navigation plot, watching the white dot representing their ship march south toward the red X, which annotated the position of the Russian torpedo. However, its location was only approximate, reconstructed from USS Pittsburgh’s encounter with the two Russian submarines. The course, speed, and range of each Russian submarine were only estimates, as was the location where the torpedo impacted Alexander’s hull. To find the torpedo on the bottom of the Barents Sea, they needed a more precise location.
Wilson waited patiently while Sonar searched for the torpedo’s end-of-run pinger, a high-frequency emission that sounded like a bird chirp. The end-of-run battery contained limited power, so the frequency was high, making the detection range short. Fortunately, Michigan’s crew knew where to look.
“Conn, Sonar. Detecting torpedo end-of-run pinger, bearing one-seven-seven.”
Bradley acknowledged, then ordered, “Helm, come left to course one-seven-seven.”
The Helm complied and Michigan altered course three degrees to port. They now knew in what direction the torpedo lay, but not how far. Michigan, like the other Ohio class submarines, had no active sonar system, but not even the most sophisticated system aboard the newest fast attacks could discern a torpedo on the bottom. They’d have to get close, then rely on the SEAL’s MK 1, MOD 0 eyeballs.
Michigan steadied on course one-seven-seven at five knots, with Sonar reporting the bearing to the torpedo every ten seconds until it suddenly vanished.