Shadow Divers

The book explains the unique dangers of deep-sea shipwreck diving. In contrast to its “cousin,” scuba diving, deep-sea diving poses a much higher risk of death. One of the main hazards is an elevated risk of nitrogen narcosis, a condition in which judgment and motor skills become impaired. In the pressure of deep water, the air in the divers’ tanks becomes denser, so divers breathe in more nitrogen than their bodies can handle. Divers describe nitrogen narcosis as similar to intoxication or anesthetic; it causes clumsiness, erratic emotions, and even hallucinations, leading to decompression sickness, or “the bends.” When a diver starts back up to the surface, they must take periodic breaks at different pressure levels to safely release the accumulated nitrogen in their system. If they rise too fast, the nitrogen in their bloodstream forms big bubbles that block circulation. This causes excruciating pain and sometimes paralysis and strokes. Nitrogen narcosis can cause a diver to panic and try to swim to the surface as fast as possible, leading to decompression sickness.

Nitrogen narcosis and the bends are dangers that originate inside a diver’s body, but the dangers of the wreck itself are just as frightening. Each diver brings “175 pounds of gear” with them into the water, including two air tanks, lights, tools like hammers and crowbars, safety lines, and breathing apparatuses. All these things are necessary for survival but complicate navigating in a wreck. A diver descends through the water along an “anchor line,” a weighted grapple dropped into the water intending to snag it on the wreck. This is the diver’s lifeline, leading them down to the wreck and back up to the boat. After entering a wreck, divers face different challenges. The structures are deteriorated, while cables and rails poke out that can snag a diver or damage equipment. Wrecks often settle on their sides or upside down, which makes navigating through them difficult. Flipping perspectives to navigate an upside-down space is challenging in itself, but for a diver with narcosis, it becomes terrifying. The movements of a diver kick up blinding “silt clouds.” In this zero-visibility scenario, panic can easily overtake a diver. The hazards of a shipwreck rarely kill divers; instead, deaths usually result from narcosis-induced panic and resulting bad decisions. Experienced divers know to doubt their emotions and instead rely on their training, ignoring their panic or their determination to reach a location or recover an object, in favor of survival.

Panic is the reason that deep-sea divers, unlike scuba divers, usually dive into wrecks alone. Scuba divers always use a “buddy” as a safety measure, but deep-sea divers know that a narcosis-addled brain can easily lead to injuring or even killing a partner. Likewise, a partner might try to rescue another diver in trouble but kick up more silt or block an exit, killing them both in the process. In 1988, a diver on the Seeker named Joe Drozd, despite his skill and experience, succumbed to panic and endangered fellow divers. Believing that he had drained both of his tanks of oxygen when he had only drained the first, he started to struggle and panic. The two other divers with him noticed his distress and tried to get him to safety. In the throes of narcosis, Drozd attacked them both with his knife, and they had to let him go to stay safe. He drowned with a full tank of air on his back. The other divers survived, though it was a close call since they had wasted decompression time in trying to save Drozd’s life. Drozd’s tragic death illustrates how divers are often their own greatest threat while deep-sea diving.

The Seeker finally reached the coordinates of the mystery wreck after a six-hour journey on the ocean. The 14 crew members, all experienced divers, planned to descend to the wreck either solo or in pairs. Using sonar, Nagle and Chatterton located the wreck, observing with trepidation that it was at least 230 feet deep, which is an unsafe depth even for the most experienced divers. Nevertheless, Chatterton decided to risk it. He set up a signal, planning to release two Styrofoam cups to the surface if the wreck was nothing important or was too dangerous, and one cup if it was an actual sunken ship that was safe to explore.

Chatterton descended carefully. When he reached the wreck, he landed on a “mass of metal” (46) and determined that it was in fact a ship. He decided that it was safe to dive and released one cup as a signal. On the surface, the other divers celebrated and prepared to enter the water. Continuing to explore the wreck, Chatterton first thought it was an old garbage barge, a type of boat that Americans used to fill with garbage, send out to sea, and then purposefully sink. However, he noticed a strange hatch, angled inward, on the ship’s surface. Further exploration revealed an intact torpedo, and Chatterton realized that the wreck was a submarine. Initially, he doubted this discovery, believing it was a narcosis hallucination. After investigating further, however, Chatterton realized that this was the “holy grail” of dive sites.

Chatterton ran out of time and started to ascend, pausing to decompress. After diving to this depth, it would take about an hour to get back to the surface. He met another diver from the boat and used a writing slate to communicate with him, writing the word “SUB” in large letters. Overjoyed, the diver turned back to relay the news to the rest of the crew while Chatterton decompressed.

The crew was thrilled at the chance to dive into a submarine wreck. The explorations of other divers confirmed Chatterton’s observations. They speculated about the submarine’s identity. Gradually, they became convinced that it was a German U-boat, a World War II submarine used in naval warfare. This find was unprecedented. Characteristically guarded, Nagle, Chatterton, and the crew all swore to keep their find an absolute secret to prevent others from coming in and plundering their find. Nagle was especially worried about his rival, Steve Bielenda. Nagle despised Bielenda, another well-known and respected diver, for his commercial success and publicly disparaged him for “following the money” (56) and exploring only established wrecks that posed no danger. Bielenda, meanwhile, called Nagle a “drunk” who endangered his customers. If Bielenda found out about the wreck, he would immediately charter his own expedition.

The secret lasted “nearly two full hours” (60). One of the divers called his friend, Richie Kohler, a passionate deep-sea diver and an avid history scholar with an interest in Germany. The diver knew that Kohler would be ravenous at the thought of an undiscovered U-boat. In addition, Nagle, despite having sworn everyone to secrecy, spilled the secret (while intoxicated) to a friend who had to bow out of the trip. Soon, the diving world was buzzing with the news of a huge find.

Chatterton, meanwhile, dreamt of the treasure he might find on a sunken U-boat. Over the next week, he speculated about the identity of the sub with Nagle, cross-referencing it with military records. None of the U-boats recorded as having been sunk off the East Coast matched up with the wreck’s location, leaving the identity of the boat a mystery. Chatterton flew to Chicago to visit the Museum of Science and Industry, home to the German U-boat U-505. He walked through the boat with other museum-goers, memorizing every detail to aid him in further exploration.