18 MTR March 2011
Craig Thorngren never thought he would grow up to be
one of the U.S.’s leading experts on underwater robotics.
His initial interests were in Law Enforcement. He joined
the US Coast Guard at 18 as a way to get the government
to pay for his education. He was involved in increasingly
important positions around the U.S. until December 11,
2001. That changed everything for the USCG.
Part of the increased focus on terrorism was the threat of
explosive devices planted on ships or docks. The USCG
was tasked after 9/11 with preventing that from happen-
ing, along with new terrorism prevention missions. The
USCG embarked on a program of thirteen Maritime
Safety and Security Teams, located at tier one ports
throughout the country. Each would be equipped with
the best underwater Remotely Operated Vehicles (ROV)
and accessories from VideoRay LLC of Phoenixville,
Pennsylvania. The first one – number 91101 – was estab-
lished in Seattle Washington, and the first person assigned
to develop an ROV team was Craig Thorngren.
After several years working the Seattle MSST ROV team
and working with the USCG to develop tactics and tech-
niques to use this new technology to keep US ports safe,
Craig retired from the Coast Guard in 2007, taking a
position with a Seattle sonar company BlueView
Technologies. Then a year later he branched out on his
own, taking advantage of his pioneering work on observa-
tion ROVS to form his company Submerged Recovery
and Inspection Services.
When Craig got the call in September of 2010 from his
friend Dennis Lancaster of Waterworks Resources, LLC of
Newport, Oregon, he quickly assessed the job. An expen-
sive hydrophone array belonging to scientist Joe Haxel of
Oregon State University’s Hatfield Marine Science Center
needed to be recovered. The acoustic release that should
have sent a buoy to the surface had not worked, and the
equipment - 300 pounds of it, six miles offshore, 175 feet
deep – needed to be brought to the surface. While the
location was known, a mission with divers would be
expensive and dangerous, and an alternative technique
was needed.
The data stored on the array was critical to the
Northwest Marine Renewable Energy Center, for an envi-
ronmental impact study of wave energy conversion
devices. This acoustic baseline research, sponsored by the
US Department of Energy, The Oregon Wave Energy
Trust and Oregon State University, was irreplaceable.
Joe Haxel was familiar with VideoRays, having operated
one in the Antarctic in 2006. Craig was familiar with this
kind of recovery, having been involved with several simi-
lar missions in the King County area, as well as Norway
and Australia. Dennis had worked with Craig before, and
was confident that a plan would be successful. The 54
foot R/V Elakha from Oregon State University was
booked for five hours. With travel time to and from the
site, there was a three hour window to locate and assess the
condition of the equipment, develop a plan for recovery,
and execute the plan successfully.
The first dive was planned to find the array, assess the
condition of the equipment and the recovery lines, and
develop a retrieval plan. A BlueView P900-130 multi-
Video Ray and
Acoustic Hydrophone and Data Recover off of Oregon
LEFT: The Hydrophone is located in “snow-blind” conditions at 176 ft. with the VideoRay Pro 4 ROV outfitted with
multibeam sonar. The buoys to bring the apparatus to the surface released but became entangled as seen here.
CENTER: A carabiner with retrieval line is held in the VideoRay ROV Manipulator Arm as it follows the Pro 4 sonar
equipped “guide” to the recovery line of the apparatus.
RIGHT: The ROV snaps the carabiner onto the recovery line and releases the carabiner from the Manipulator Arm.
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