by Mary Roach
A BALLISTIC MISSILE submarine will take you to the remotest places you’ll ever travel and show you none of it. The sub has no windows or headlights, nothing to make it visible in the surrounding black. Below the depth that sunlight penetrates, a periscope is useless. The crew see by sonar, picking up propeller sounds from ships and plotting their distance and course. To remain undetected, ballistic missile subs use passive sonar only: no pinging. Echolocation—sending out sound and timing its bounce-back—would give away the sub’s own location. The Tennessee is blinder than a bat.
At 450 feet down, our current depth, there are no other vessels to smack into. (Each sub has an assigned territory, or “box,” extinguishing the infinitesimal likelihood that two of them might collide.) The biggest danger outside at the moment is shrimp. When galley crew empty the grind bucket, vast schools of snapping shrimp rush the hull to feed. Their collective tumult can mask engine noise from other vessels.
In the sonar shack this morning, four men sit at monitors, watching snowy green crawls of sonar feed and listening through headsets. A sonarman can identify a ship by propeller noise the way a birder might distinguish one woodpecker species from another by the speed or timbre of the hammering. Someone passes me a headset to hear the click-jabber of some porpoises. After a few days in a submarine, any contact with nature can be a bit heady. “Flipper!” I hate to apply the verb squeal to myself, but that’s what it is.
“Uh huh,” says the sonarman. “Flipper all night long.”
Although ballistic missile subs are able to stay deep for months, they typically do not. The Tennessee surfaces regularly, like a whale, to exhale emails. We’re about to come up in a merchant transit lane, which has everyone a little on edge. In the hour-long lead-up to the moment when the sub breaches the water’s surface, someone’s been at the periscope, face pressed to the eyepiece, scanning for anything sonar might have missed. Because the view is less than 360 degrees, he circles slowly, around and again, crossing one leg behind the other, a slow dance with a canister vacuum. You want to be very, very sure there’s nothing up there.
In 2001, the USS Greeneville surfaced directly beneath a 191-foot Japanese fishery training ship. The sub’s rudder sliced the hull, causing the trawler to sink and resulting in the death of nine people aboard. (Sleep deprivation wasn’t cited as a contributing factor. A group of visitors was: fourteen CEOs and, um, a writer. All but one of the group were up in the control room, crowding the periscope platform, blocking access to critical displays, distracting the sonarmen.)
The captain of the Greeneville exhibited what is known in these parts as poor periscope discipline. He scanned for about half as long as procedure called for. Another potential danger for a surfacing sub is “bow null.” If the front of a ship points straight into a submarine’s sonar array, the sound waves emanating from that ship’s propulsion are blocked by its own body and cargo. The Tennessee’s safety officer compares it to “yelling through the trunk of a car to your kids in front of the car.” A helpful, if disquieting, metaphor.
It’s the weekend, which can be a more dangerous time to come up. Container ships that are nearing a port outside standard work-week hours will sometimes loiter, timing their arrival for Monday, when pay scales drop back to normal. A container ship is the size of a strip mall, but if its engines are silent, it’s all but invisible to the crew of a ballistic missile sub. Aboard the Tennessee, a sailboat is more worrisome than a warship. Now you understand how it came to pass that the USS San Francisco, in January 2005, ran into an undersea mountain. They’re very quiet, mountains.
Adding to stress levels: Last-ditch evasive maneuvers are out of the question. A surfacing ballistic missile sub is traveling between 6 and 12 miles per hour. “It’s like a baby crawling out of the way of a truck,” says the safety officer, as though yelling through the trunk of a car that there may be something just a little bit off with him.
Extreme caution is ever the mind-set. If a new sonar contact should appear on the screen during surfacing, an “emergency deep” may be ordered. Because without echolocation, you don’t immediately know how far off the other vessel is. “Be safe now and figure it out after,” the commanding officer said yesterday, as we dove to avoid a ship that would turn out to be several miles off. A ballistic missile sub is a boat without a destination, its course a series of evasions and nervous retreats. Any time a contact is calculated to be within two miles, the commanding officer is called. And, often, the navigator and the executive officer.
And there goes another night’s sleep. “I expect to be woken three or four times per sleep,” the navigator told me. Murray wakes up, too, because he has a speaker mounted on the wall of his stateroom, above his pillow, that picks up the conversation in the control room. He’s like a new mother with a baby monitor on the nightstand. “All of a sudden, out of a lot of background noise and chatter, you’ll catch a certain word or a change in the tone or volume of somebody’s voice. It just snaps you out of a sleep.”
Unsurprisingly, submariners have a robust tradition of caffeination.‡ The Tennessee left port with a thousand pounds of coffee. The world’s first nuclear-powered submarine, built in 1954, is now a floating museum in Groton, Connecticut, and if you tour it, you will see metal rings bolted to consoles and bulkheads at the different watch stations: cup holders! Caffeine is safe and effective but not without a downside. Depending on one’s sensitivity, it has a half-life of six to eight hours. Even if you have no trouble falling asleep after drinking coffee late in the day, you may wake more easily during the night because your nervous system is still aroused, your brain attuned to sounds and other stimuli that would otherwise go unheeded. The more poorly you sleep, the more caffeine you tend to consume the next day, and the more lightly you sleep the following night. And so on. As Murray said upon seeing me refill my mug, “That’s not a long-term solution, shipmate.”
We’re approaching periscope depth. The lights in the control room have been shut off. This is done for the benefit of the man at the periscope, who will shortly be taking a look around in the 5:00 a.m. darkness at the surface. To everyone else up here, many of whom are going on four or fewer hours of sleep, darkness is the opposite of helpful. Not only is it warm and dark in here, but because we’re nearing the surface, the submarine is now rocking gently with the swells. “Torture,” says the helmsman.
Torture was the word used by sleep researcher William Dement, who, as a student in the 1950s, helped Nathaniel Kleitman document Rapid Eye Movement (REM) sleep. Before there were eyelid electrodes and electrooculargraphs, there were grad students pulling all-nighters. “Staring at the closed eyes of human adults by the dim light of a 30-watt bulb in the middle of the night was sheer torture,” Dement wrote in a tribute to Kleitman, who is known in his field as “the Father of Sleep Research.” (Tougher yet was the job of the chaperone Kleitman insisted be present when the subject was female: watching someone else watching the eyes of a sleeping human all night.)
THE PHOTOGRAPH dates from 1938. Nathaniel Kleitman sits at a dinner table, knife and fork crossed in a slab of hickory-smoked ham. What’s unusual about this ham supper is that it took place in a cave 119 feet underground. Kleitman, with a graduate student assisting, spent thirty-two days in Kentucky’s Mammoth Cave investigating the cycles of human sleep and wakefulness. He wished to find out: to what extent are these rhythms tied to external cues and routines? If you took away the cues—sunlight, established mealtimes, regular business hours—could people slip easily into an altered routine? Going underground seemed like the easiest§ path to an answer.
Submarines interested Kleitman, because, like caves, they present a sort of real-world laboratory for chronobiology. Kleitman, in turn, interested the Submarine Force. They were, as they are today, having some alertness issues. Kleitman came up with a watch schedule that took advantage of a submarine’s isolation from sunlight—the fact that it’s always, as Murray put it, “70 degrees and fluorescent.” It should thus be possible, K
leitman reasoned, to put each of three separate watch crews on a different schedule by staggering their waking hour, each crew beginning the day at a different time.
Beginning in 1949, three submarines, the Corsair, the Toro, and the Tusk, gave the Kleitman watchbill a two-week trial. At the end of it, Kleitman distributed questionnaires. “Should new schedule replace old?” read the last question. “Yes,” said 19 sailors. “No,” said 143. What happened? Catastrophic decompensation in the galley. Rather than cooking and cleaning up one breakfast, one lunch, and one dinner every twenty-four hours, galley crew had to do three of each, accommodating the different start times of each watch group’s “day.” The cooks were exhausted and peeved. The galley was a mess—“never clear and clean for more than an hour and a half,” causing every meal to be “flavored with the odor of the last, and the whole permeated with the aura of aged refuse.” And because a submarine’s galley doubles as its rec room, movies could no longer be screened. “Recreational activities had to be curtailed to such an extent that they degenerated to periods of loafing around trying to keep out of the way.” Friends who weren’t assigned to the same “time zone” were now isolated from each other. “It is considered neither desirable nor feasible to continue this experimental watch schedule any further,” concluded the final memo in the submarine folders of the Nathaniel Kleitman Papers.
There were some in the Submarine Force who believed Kleitman’s watchbill deserved a fuller chance, that the galley and recreation routines could have been adjusted. One executive officer blamed “just plain orneriness. Sailors,” he wrote, “hate to try anything new.” It is perhaps no coincidence that the colloquialisms “don’t rock the boat” and “don’t make waves” share a nautical element.
The officer was probably right. The Kleitman watchbill was grounded in sound science. Sunlight is our most powerful internal clock-setter. Along with rods and cones, we have a third kind of photoreceptor, one that is keyed to the blue wavelengths of sunlight. Information about this light, or the lack of it, is passed along to the pineal gland, producer of melatonin, the body’s natural soporific. Sunlight triggers a cutoff of melatonin, bringing on wakefulness. (Indoor light—particularly the light from tablets and smartphones—can also suppress melatonin, but nowhere near as dramatically as sunlight.) This is why night shift workers who drive home in the morning through sunlight and then struggle to fall asleep may find relief by buying amber-lensed Bono-style glasses that block the sun’s blue light wavelengths.
NSMRL has been developing goggles rimmed with battery-powered lights that emit the blue melatonin-suppressing wavelengths, thereby fooling the brain into thinking it’s daytime. Depending on which direction you’re flying, one or another of these distinctive eyewear options can help you preadjust to a new time zone. Or, in the case of Special Operations types heading to the Middle East to undertake secret 3:00 a.m. missions, not adjust. Lieutenant Kate Couturier, a circadian rhythm researcher at NSMRL, outfitted a planeload of Navy SEALs with blue light–emitting goggles on a series of flights from Guam to the East Coast of the United States, to see if it were possible to make them unattractive to females, oops, I mean, to keep them on Guam time. It worked.
It is probably fair to say that circadian dysrhythmia affects alertness and performance as much as or more than the amount of sleep a person has been getting. In the late 1990s, a team of sleep researchers and statisticians from Stanford University analyzed twenty-five seasons of Monday Night Football scores. Because the games were played at 9:00 p.m. eastern standard time, West Coast players were essentially competing at 6:00 p.m.—a time chronobiologically closer to the body’s late afternoon peak for physical performance.¶ As the researchers predicted, West Coast teams were shown to have won more often and by more points per game. The effect was striking enough that teams sometimes travel a few days in advance of a game to give the players’ body rhythms a chance to adjust.
Another complicating factor with military sleep is that the people making the schedules are often middle-aged and the people following them are teenagers. Not only do adolescents typically need more sleep, but their circadian rhythm is “phase-delayed” compared to adults’; melatonin production begins later in the evening, with the result that a teenager or even a twenty-two-year-old may not feel sleepy until well past midnight. Horrifically, the traditional boot camp lights-out is at 10:00 p.m., with a 4:00 a.m. wake-up.
Jeff Dyche told me about an admiral who approached him wanting to address sleep deprivation in the Navy boot camps. She wanted to move lights-out to an hour earlier—9:00 p.m.—to give the lads more time to sleep. Dyche quietly took her for a walk around camp after lights-out. “Almost every sailor was sitting up wide awake, twiddling his thumbs. They’re all going to sleep at midnight no matter how early they have to get up.” Dyche managed to move some 4:00 a.m. wake-ups to 6:00 a.m. Test scores improved so dramatically that one of the command master chiefs assumed there’d been a cheating scandal.
For the past four decades, submarines have run on a watchbill known as “sixes,” which divides sailors’ time into six-hour chunks: six hours on watch, six for other duties and studies, six for personal time and sleep, then back on watch. The creation of an 18-hour day saw each sailor putting in six extra hours of watch time every 24-hour period. The problem is that his activities ceased to align with his biological rhythms. He’s now working when his body badly wants to be sleeping. “It’s like flying to Paris every day,” Kate Couturier said. Without Paris. “It’s a quadruple whammy,” said Couturier’s colleague Jerry Lamb, when I met with him and other Navy sleep experts before boarding the Tennessee. “We flip around their sleeping and working times, we work them like dogs, we give them very short periods of sleep, and we wake them up for drills.” He turned to his colleagues. “Did I miss anything?”
Lamb was involved in the push for the new “circadian-friendly” watchbill. There has been, as there always is, some resistance. Sixes is how it’s been done for fifty years. “As flawed as it is, we’d perfected it,” commanding officer Bohner said one morning as we sat in his stateroom. “Now we’re going to shake the ball and throw the pieces back down again.” I tried to picture what game that might be.
The problem resides mainly with the midnight to 8:00 a.m. shift—the dreaded “mids.” You come off watch and instead of sitting down to dinner, you’re having breakfast. You’re sleeping from 4:00 p.m. to 10:00 p.m., when there’s often, despite Nathan Murray’s best efforts, something that you have to get out of bed for. To more fairly distribute the suck, the crew swap watch schedules every other week. Instead of flying to Paris every day, it’s every two weeks. The switchover happens on a Sunday, its being normally—that is, when riders are not coming aboard creating extra work for everyone—the quietest day of the week.
Today is that Sunday. Lieutenant Kedrowski, the man on the periscope platform, the officer of the deck, is switching to mids. It’s his birthday. Happy birthday, Kedrowski. You get to scramble your circadian rhythms and get three hours sleep—in a rack that smells like someone else, because you had to give yours up to some writer from California.
“I’m really sorry, by the way.” I would have been happy to sleep among the warheads.
“It’s no problem,” says Kedrowski, with unforced bonhomie. Almost everyone I’ve met down here has been easygoing and upbeat, especially given how tired they must be. I am, to quote the Dole banana carton in the galley pantry, “hanging with a cool bunch.” If everyone in the world did a stint in the Navy, we wouldn’t need a Navy.
Up above Kedrowski’s head, a red light is flashing. Kedrowski explained this alarm box earlier. It’s the one that goes off if the President of the United States orders a nuclear missile launch.
“So this is another drill then?”
“No.” Kedrowski finishes writing something in a three-ring binder and looks over at the box. “It’s kind of broken.” He puts down his pen and listens. “They’re supposed to say, ‘Disregard alarm.’” The
y don’t, and soon it stops. “They need to fix that,” he says.
The missile alarm is mildly unnerving (good god, what if?) but not particularly frightening. In the queer logic of war in general and nuclear conflagration in specific, five hundred feet underwater on an undetectable Trident submarine is the safest place you could possibly be. The crew of the modern ballistic missile submarine endures long hours and grueling tedium, homesickness, horniness, and canned lima beans, but they are spared the thing that keeps most of us out of the military: the nagging awareness that you could be shot or blown up at almost any moment. Better dead-tired than dead.
___________
* In military slang, there’s a friendly epithet for everyone. I, for example, am a “media puke.”
† By weight, a submarine carries more paperwork than it does people—despite the best efforts of Vice Admiral Joseph Metcalf III. Metcalf, who led the invasion of Grenada, waged an equally headstrong campaign for shipboard computerization—“a paperless ship by 1990,” he told the New York Times in 1987. He calculated that even a smaller surface warship carries 20 tons of technical manuals, logs, forms, and shelving—tonnage that could be used for fuel or ordnance. Metcalf’s battle cry (“We do not shoot paper at the enemy”) attracted some media attention and probably one or two spitballs, but—if the USS Tennessee is any indication—no serious commitment to change.
‡ To reduce troops’ load, the Army adds caffeine to gum or mints or foods that soldiers are already carrying, like jerky. Natick public affairs officer David Accetta feeds a Caffeinated Meat Stick to reporters who visit the food lab. To me, it tasted just like you’d expect caffeinated meat to taste. Accetta was taken aback. “Brian Williams loved them.” Or did he?