China returns seized undersea drone to U.S. Navy
WASHINGTON, Dec. 20 (UPI) — Four days after a Chinese ship snatched one of the U.S. Navy’s undersea drones out of the water, the unmanned exploratory vehicle was returned to the United States amid continued sniping between the two countries.
The U.S. Navy Ocean Glider Unmanned Underwater Vehicle seized by China on Dec. 15 was returned to Tuesday morning as the USS Mustin received the UUV in international waters near where the drone was first picked up a Chinese salvage ship.
“This incident was inconsistent with both international law and standards of professionalism for conduct between navies at sea,” Pentagon press secretary Peter Cook said in a statement. “The U.S. has addressed those facts with the Chinese through the appropriate diplomatic and military channels, and have called on Chinese authorities to comply with their obligations under international law and to refrain from further efforts to impede lawful U.S. activities.”
The vehicle was conducting a pre-programmed military oceanographic survey on Dec. 15 in the South China Sea and, as it was returning to the USNS Bowditch, was picked up by the salvage ship.
China said the drone was unidentified and could pose a threat to safety, calling their seizing of the UUV and effort by crew on the ship to identify it. China also claims the drone was in Chinese waters. The Pentagon, however, said the UUV was in international waters when it was snatched while gathering unclassified data to help submarines navigate in murky water.
The South China Sea is hotly contested by the nations surrounding it, with China attempting to claim most of it. Even if China’s claims were widely acknowledged, which they are not, the U.S. could still legally use drones for the type of exploration the Navy was conducting, according to experts.
U.S. and Chinese officials quickly worked out the UUV being returned, with the Chinese saying the exchange was set up with “friendly consultations,” though officials at the Pentagon say they will continue investigating the situation.
Original post upi.com
Slocum Sub-surface Electric Gliders
The Slocum electric gliders can be deployed for up to thirty days and travel up to 1500-km (longer using Lithium batteries) collecting scientific data from depths of 5 to 1000m.
The gliders are manufactured by Teledyne Webb Research and are classified as Autonomous Underwater Vehicle Gliders (AUVGs). The ~6ft long pressure hull is made of carbon fiber and aluminum and has a payload bay for a standard or custom suite of instrumentation. Data transfer and communication is accomplished via Iridium or radio frequency (RF) modem .
These gliders use a change in buoyancy to change vehicle pitch and create forward motion. An external oil bladder is filled or drained to change buoyancy and the wings convert the vertical velocity into forward movement. Multiple ascents and descents create a vertical sawtooth trajectory. The glider navigates to waypoints by using surface GPS fixes to apply corrections to dead reckoning.
A team of two can easily deploy and control several gliders from a small boat and access to the internet.
Slocum glider diagram
courtesy of Teledyne Webb Research