Showing posts with label submersibles. Show all posts
Showing posts with label submersibles. Show all posts

Thursday, August 6, 2009

New Submersible Designs Open Up Ocean Exploration

There is room for plenty of design innovations in ocean exploration. Armed with better batteries and stronger materials, new submersibles aim to go deeper than ever before and open up the unexplored ocean.

By liberal estimates, we’ve explored about 5 percent of the seas, and nearly all of that in the first 1,000 feet. Now engineers want to unlock the rest of the sea with a new fleet of manned submersibles. With the world’s highest mountains and both poles explored, the deep seas are a ripe frontier.

But sending a vehicle that deep requires new engineering and design. The craft must be small enough to move on battery power and sturdy enough to withstand immense pressure—10,340 pounds of water per square inch at 23,000 feet, equivalent to having a school bus on your head.

In 1960, American naval lieutenant Don Walsh and Swiss engineer Jacques Piccard made the only expedition to the world’s deepest point, piloting a 50-foot, submarine-like vehicle called the Bathyscaphe Trieste 35,800 feet down to the bottom of the Marianas Trench. They spent 30 minutes on the bottom of the world before surfacing with their glass viewing ports cracked by the pressure. No one has been back since.

There’s a heated debate among oceanographers over whether the next generation of deep exploration should be performed by robots, humans or both. The argument for remotely operated vehicles (ROVs) is led by oceanographer Robert Ballard, who gained fame in manned subs, discovering the first hydrothermal vents and exploring the wreck of the Titanic. Others argue that collecting samples from the seafloor is easier when a person is in the pilot’s seat, and that no machine can replicate the panoramic scope of human vision.

Today only five manned subs can dive to 15,000 feet: the French Nautile; two Russian submersibles; Woods Hole’s Alvin, which Ballard used to explore the Titanic; and the Japanese Shinkai 6,500, the world’s deepest-diving sub, which is capable of descending to 21,000 feet. As a result, manned deep-sea exploration is incredibly inefficient.

Click on the heading above to read the complete story on the Popular Science website.