ARLINGTON, Va.-The muscular U.S. Navy diver hoisted a 60-pound life-support
regulator onto his back, then donned a 30-pound metal helmet.
Fellow divers connected his diving suit to an "umbilical" hose pumping in
breathing gas and establishing communications with the surface. After
receiving approval to hit the water, the diver descended into a large test
pool at Naval Surface Warfare Center Panama City (NSWC), Florida-home to the
Navy Experimental Diving Unit.
The diver's mission: demonstrate the effectiveness of the MK29 Mixed Gas
Rebreather-a new prototype system that's the first of its kind within the
Navy diving community, developed by NSWC Panama City.
The technology is sponsored by the Office of Naval Research Global (ONR
Global) TechSolutions program. TechSolutions is ONR Global's rapid-response
science and technology program that develops prototype technologies to
address problems voiced by Sailors and Marines, usually within 12 months.
"This rebreather system is an awesome opportunity to enhance the
capabilities of Navy divers and accelerate their deployments," said ONR
Command Master Chief Matt Matteson, who heads up TechSolutions.
Navy diving missions include underwater rescues, explosive ordnance
disposal, ship hull maintenance, recovery of sunken equipment, and salvage
of vessels and aircraft.
Beneath the waves, Navy divers breathe a careful mixture of oxygen and
nitrogen. Below 150 feet, however, nitrogen becomes toxic-leading to
nitrogen narcosis, a drowsy state that can dull mental sharpness severely
and jeopardize safe return to the surface.
The solution is to replace nitrogen with helium. However, helium is
expensive and hard to obtain because of recent worldwide shortages. And the
Navy needs a lot of it for missions and training exercises, requiring
canisters of the gas to be transported on accompanying ships or planes.
The MK29 rebreather solves these problems. Used oxygen-helium is filtered
through a carbon dioxide scrubber-which removes carbon dioxide and recycles
the breathable gasses back to the diver.
The result? Very little venting (giveaway bubbles)-or wasted helium.
"The MK29 decreases helium requirements by approximately 80 percent," said
Dr. John Camperman, a senior scientist overseeing the development of the
MK29 at NSWC Panama City. "Divers can perform more dives with the same
amount of gas, or bring less helium."
Test results suggest this system will be a major asset to Navy divers-who
can not only perform more dives, but also stay underwater longer if surface
supply gas is interrupted.
The MK29 even reduces breathing noise and fogging of helmet viewports. It's
also the first piece of Navy diving equipment to feature 3D-printed titanium
tubing that connects hoses from the helmet's breathing manifold to the
regulator backpack. That titanium reduces the risk of breathing hoses being
sliced by sharp or jagged underwater objects.
The idea for the MK29 came from a NSWC Panama City master diver, who
contacted TechSolutions seeking a way to reduce helium consumption while
using newly available rebreather technology. Recognizing the expertise of
Camperman and his team, TechSolutions asked them to develop the MK29.
Camperman's research team will conduct further MK29 tests this year-and hope
to see the rebreather issued throughout the fleet by next year.
Watch the video, https://youtu.be/rCbPlSGrXZ8, of the MK29
Warren Duffie Jr. is a contractor for ONR Corporate Strategic
Office of Naval Research