The Hindenburg wasn’t delivered down through lightning, static, or sabotage. History’s maximum well-known airship turned into destroyed through helium. Or rather, the dearth thereof. The zeppelin’s Nazi developers balked on the charge of this uncommon, lighter-than-air fueloline. So instead, they stuffed the blimp with hydrogen, that’s tons much less highly-priced, simply as buoyant, however manner extra explosive. So irrespective of what chain of occasions led as much as the explosion, it turned into helium’s shortage that killed the airship. And today, the equal fueloline—uncommon as ever—is placing a primary cramp in deep sea diving operations.
The US Navy’s divers are accountable for a extensive kind of salvage and rescue tasks, from prying sunken wrecks off the ocean ground to bringing distressed submarines to the floor. But each one of these divers desires oxygen it really is reduce with highly-priced helium (as opposed to nitrogen, which makes up maximum of the atmospheric cocktail we breathe at the floor). So to lessen fees—an allow extra missions—the Navy has evolved a brand new diving equipment that rescues the helium from a diver’s exhalations.
For shallow diving, a combination of oxygen and nitrogen is fine. But nitrogen is awful for deep divers, due to the fact it is impractical for them to ascend slowly sufficient to save you the fueloline from inflicting the bends and different agonizing physiological conditions. So for deep operations, divers get pumped a combination of oxygen and helium from the floor. “But metabolically, the diver’s most effective used approximately five percentage of the helium fueloline in every breath,” says John Camperman, the senior diving and existence help scientist on the Naval Experimental Diving Unit in Panama Beach, Fl. A lot of oxygen receives wasted this manner, too, effervescent away to the floor with each exhale.
Divers ought to re-use that exhaled air, the usage of up the relaxation of the oxygen and helium, if most effective for all of the carbon dioxide that incorporates it. The solution? A healthy that recycles the air returned right into a breathable composition. “Instead of exhaling your complete breath into the ocean, you presently are exhaling right into a carbon dioxide scrubber,” says Camperman, whose lab evolved the technology. The scrubber, carried in a backpack, is genuinely a canister complete of granular calcium hydroxide. This fabric chemically binds to carbon dioxide molecules, pulling them out of the diver’s grimy breath. Now, as opposed to of flooding the diver with sparkling air, the deliver from the floor is a measured trickle. “It operates at the precept of injecting simply the proper quantity of helium and oxygen to preserve the stability of gases,” says Camperman. He says the rebreather saves approximately eighty percentage of the helium from every breath.
This % might not simply scale back the Navy’s helium budget. “It additionally reduces the scale of our logistical footprint,” says says Warrant Officer Coy Everage, the diving officer on the Navy’s Explosive Ordinance Disposal unit primarily based totally in Little Creek, Va. (The explosive ordinance agencies cope with the Navy’s salvage and rescue operations.) This is due to the fact cylinders of oxygen and helium absorb quite a few space, and reducing down on that load will assist positioned divers wherein they want to be loads quicker. “Figuratively speaking, it is loads less complicated get on Delta Airlines with a suitcase as a carry-on as opposed to bringing aboard an entire truck,” says Everage. (Figuratively, due to the fact looking to carry even a shampoo-bottle sized field of compressed fueloline on a business airliner might get you placed on the TSA’s naughty list. Navy divers circulate their compressed gases across the world—carefully!—the usage of Navy planes and ships.)
Reducing helium fees may also supply the Navy cause to rethink salvage operations that were sidelined, says Camperman. And in contrast to the Hindenburg, reducing down on helium in all likelihood isn’t always going to purpose any subsurface explosions.