Collapse Depth

For example: he knew the combination of the inner SAS safe, the safe-within-a-safe that held the sealed authentication codes that would allow the launch of a nuclear missile. That series of four double-digit numbers was so secret that he was not allowed to write it down, and he had nightmares about being summoned to radio at the start of World War III and being unable to remember it, his faulty memory removing Alabama from strategic service as surely as an enemy torpedo. And, as navigator, he knew the exact locations of their patrol areas, the vast swaths of ocean where Ohio-class submarines maintained their vigils, within missile range of their targets in China and eastern Russia. That kind of targeting information was so secret, classified beyond Top Secret, that even the name of the classification was unutterable to the vast majority of the ship’s 154 man crew.

He knew the ship’s top speed: not as fast as many novelists speculated, slower than a good speed boat, but impressive enough to those who understood how quietly their 18,000 ton warship could move beneath the ocean at that speed. And he knew the ship’s test depth, the deepest at which they ever operated, the depth at which their systems were tested against the maximum sea pressure they should ever face. More secret still, he knew the ship’s collapse depth, the depth at which engineers estimated that the hull would finally succumb to the pressure of the millions of tons of sweater that surrounded them. It was striking what sea pressure could do to the works of man at those depths, the way water could turn into a force as solid and destructive as any weapon. Their XO had a standard lecture he liked to give about the nature of submarining, how seawater was their only real enemy. Torpedoes and depth charges just allowed the enemy inside.

Unlike the ship’s relatively unimpressive top speed, its maximum depth would be striking to anyone knowledgeable about diving and submersibles, a very large number that was a monument to the engineering marvel that was a Trident Submarine. But, as the navigator knew and was reminded of every time he so much as glanced at the small, italic numbers that dotted every one of his charts: even that large number was very much smaller than the depth of the ocean almost everywhere that they operated. Another favorite monologue of the XO’s: he would hold his hand out at waist-height, the distance to the deck representing the depth of the Pacific. Test depth is here, he would say, pointing to a spot about four inches below his palm. The submarine could travel deep, but the Pacific was very much deeper, a kind of biblical abyss that was difficult for the mind to grasp, even the minds of men who’d spent their whole lives at sea.

But the navigator had another, even darker secret, one more frightening than a forgotten safe combination or the depth at which a submarine becomes destroyed by a heartless ocean, a secret that tortured him as he tried to stay focused on the charts: he knew the ship’s mission. Along with the captain and the XO, he’d seen the new orders that he feared would doom them. Doom humanity. As navigator he not only knew about it: he had to help plan it, and plot their course right into the belly of the beast. He envied the rest of the crew in their ignorance, their hectic, boisterous preparations for patrol.

“Nav, are you alright?”

The navigator looked up, startled. The Duty Officer, Lieutenant Maple, was staring at him from the conn. He’d stopped signing the thick stack of red DANGER tags in front of him and stared with concern.

“Yes. I’m fine.”

“You’re bleeding.”

The navigator looked where Maple was pointing. He’d been jamming the point of his dividers into his knee. He’d stabbed right through the fabric of his khakis, into his flesh. Blood ran down his leg into a dark red puddle on the deck.

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