On a blustery, cool autumn day, two divers at Naval Undersea Warfare Center Division Keyport, Washington, donned wetsuits, helmets and a tangle of hoses to hop into Liberty Bay for routine training. Four fellow divers from the Keyport Dive Locker circled them to make sure all the various pieces of equipment were hooked up and working correctly.
It wasn’t a necessary training, but one that couldn’t hurt considering the missions the sailors of the Dive Locker are called to perform.
The Keyport Dive Locker, which is a facility of expert dive personnel, equipment and storage, has a vast mission. They help to test and recover lightweight torpedoes, take part in unmanned underwater vehicle operations and do salvage and demolition work. The divers also take care of the upkeep to ships’ hulls, rigging and equipment, and their expertise is often contracted out to other Navy bases around the Pacific Northwest.
“Every day here is different,” said Navy Petty Officer 1st Class Andrew Turner, the diving supervisor at the Keyport Dive Locker. “Not a lot of diving units do as many different operations as Keyport does.”
One of those operations includes a unique agreement with Canada going back to 1965 in which Keyport Dive Locker personnel take part in the testing and evaluation of torpedoes dropped from helicopters into waters near a joint test facility on Vancouver Island. Three U.S. civilians also work on the island full-time to support the Canadian navy.
Keyport’s divers range from brand-new sailors fresh out of dive school to those with decades of experience, making it a good training ground for younger, more inexperienced divers.
A One-Stop Shop Portable Diving System
Back out on the bay, Navy Senior Chief Petty Officer Alejandro Delapena and Navy Chief Petty Officer Buster Eastland demonstrated a typical dive using the portable Fly-Away Diving System III, which can accommodate three divers at a time.
The system attaches an umbilical hose to each diver that includes four hoses — one for air; one for helmet-to-surface communications; one that measures diver depth, called a pneumofathometer; and one for hot water that’s heated on the surface and used to warm divers in cold water. Fellow divers monitor and operate the system from a trailer on the surface.
The air hose operates with a primary and reserve air bank, and in case of emergency, each diver also carries an independent air supply on their back with enough air for them to make it back to the surface. The FADS-III system is certified to use air as a breathing medium up to 190 feet of seawater. To execute deeper dives — from 190 to 300 feet of seawater — a calculated mixture of helium and oxygen, a portable recompression chamber and other ancillary diver life support systems are used to safely decompress the divers.
“For dives deeper than 100 feet of seawater, a diver’s going to start feeling a narcotic effect … it’s almost like a euphoric effect, like you’re drunk, or you’re just not thinking very clearly,” Turner said, referring to that effect as nitrogen narcosis. For deeper dives, “we’ll replace the nitrogen with helium, which does not have that same narcotic effect. And we can mix whatever percent of oxygen into that as we want, depending on the mission set.”
After Eastland’s and Delapena’s gear was checked by their fellow divers, the pair spent about 15 minutes at a depth of about 35 feet of seawater — just another day on the water for them.
The Historic ‘Whale’
The Keyport Dive Locker is also home to the 94-year-old “Whale,” the oldest certified active recompression chamber in the Defense Department. It’s used by naval facilities throughout the Pacific Northwest for treatment of diving illnesses, as well as hyperbaric oxygen therapy, which can help treat other various ailments, illnesses and medical conditions. The chamber also helps to fight infections and wounds that haven’t been able to heal from severe injuries. Recently, it was used to help an injured naval officer recover from a harrowing bicycle accident.
The Whale is also used as a simulator to pressure test dive school candidates — from Navy SEALs to explosive ordnance disposal technicians and civilians — to see if they can physically handle the depths Navy divers reach.
“It will basically prove to the Navy and us that you can clear your ears up to a depth of 60 feet,” Turner said.
According to Navy Chief Warrant Officer 2 Chris Lansford, having correct inner-ear anatomy and being able to equalize your ear pressure are prerequisites for the Navy’s dive school.
“We have a high percentage of people that cannot equalize their ear pressure with the atmospheric pressure, and we’ll have to stop at a very shallow depth before it damages anything,” Lansford said.
The chamber is also a claustrophobia test. “Some people like open ocean … but we try to put them in this relatively large metal tube compared to some of the other [chambers], and they’re like, ‘Nope, not doing it,”’ Lansford explained.
Dive Locker personnel are trained in how to keep potential panickers calm because the chamber has to slowly be depressurized, meaning they can’t pull candidates out quickly if they’re already at depth.
“With that pressure — the things that it does to the body and the gases in the body — we do have to come up slow,” Turner said. For the most part, he said, most people who do have claustrophobia issues make it known when they’re being briefed by the testing supervisor before any pressurization begins.
Some of the other side effects one might notice while in the chamber could be fatigue from breathing and moving the weight of the air, which is heavier the deeper you go, the divers said.
“You can’t whistle because the air density is different. Your voice changes because of the air density,” Lansford said.
Other Navy Dive Lockers and operational units all over the world that see barotrauma or decompression injuries use similar recompression chambers. For naval divers stationed at Keyport, preparing others for dive training and helping people get better is all in a day’s work.
