High-Tech Devices Provide Eyes on Ocean Bottom
HAMPTON BAYS, N.Y. (AP) _ It’s a scene to rival Jules Verne: a high-tech fleet of nautical robots fitted with cameras, mechanical claws and lasers, sent into the depths of the Atlantic to solve a great mystery.
But the work is not fiction. An array of remote-controlled devices have been used to aid divers in recovering bodies and wreckage from the explosion of TWA Flight 800.
With the recovery effort nearing the end of its fourth week, the high-tech tools are playing a key role, Navy officials said.
The most sophisticated tool _ an experimental device called a laser-line scanner _ recently completed a meticulous survey of an area where the first parts of the jumbo jet plunged into the ocean on July 17.
The USS Grapple, one of two salvage vessels on the scene, used the survey to collect items that _ while widely scattered and mostly small _ could prove crucial to investigators trying to determine why the Boeing 747 exploded.
Developed during the Cold War by Science Applications International Corp. of San Diego, the laser-line scanner previously has been used to inspect underwater oil lines and archaeological sites.
The ungainly, box-shaped ``LLS″ projects a blue-green laser beam toward the bottom in 70-degree sweeps, somewhat like painting a wall. Unlike the shadowy images of ordinary sonar, it can deliver distinct images, even detailing rivets and serial numbers on metal plates.
The device also can identify ``soft targets″ that often do no register on sonar. In the TWA search, the scanner found several bodies, including two that sonar missed, the Navy said.
Other devices probing the depths illuminate wreckage for divers and sometimes lift pieces with mechanical claws operated by remote control from the decks of the recovery fleet. The Navy has scanned more than 70 square miles during the operation.
Within days after the jetliner exploded in flight, killing all 230 aboard, the Navy salvage effort included: a National Oceanic and Atmospheric Administration ship carrying a side-scan sonar to map the ocean floor; remote operated vehicles aboard the USS Grasp and the salvage vessel Pirouette; and the Deep Drone 7200 _ a powerful submersible that can dive to 7,000 feet and lift 3,200 pounds while videotaping every move _ aboard the Grapple.
The Deep Drone’s ability to stay under water indefinitely while recording the scene and collecting objects make it useful even for widely scattered debris, said Lt. Nicholas Balice, a Navy spokesman.
``It saves the (human) divers a lot of down time, and just because it can pick up large items doesn’t mean it can’t pick up small ones,″ Balice said.
The remote operated vehicles, or ROVs, aboard the Grasp also have video and still cameras to photograph the wreckage, enabling divers to make decisions in advance on where to go and how to approach the task with minimal risk, said Lt. Cmdr. Gordon Hume, another spokesman.
The torpedo-like ROVs are an advanced version of submersibles used in numerous Naval operations to recover crashed military aircraft lost at sea. One also was used in recovering the Challenger space shuttle in 1986, said Lee Brown of Oceaneering Inc., a private salvage firm that operates the robots under government contract.