USS Sentry
"Sentinel of the Sea"
Technology Aids Mine Hunting
USS Sentry Public Affairs

Sailors aboard the mine countermeasure ship USS Sentry (MCM 3) successfully piloted an unmanned underwater vehicle (UUV) mounted with live explosives to destroy a training mine as part of International Mine Countermeasures Exercise (IMCMEX) April 14.

“For Sentry, this was the ultimate validation of mission readiness,” said Lt. Cmdr. Lawrence Heyworth IV, Sentry’s commanding officer. “After several days of sustained operations at sea, our team successfully found, identified and neutralized a training mine. It’s the reason we’re out here.”

Mapping the sea floor with the SQQ-32(V4) mine hunting sonar, Sailors aboard Sentry can identify anomalies and classify objects as “mine-like” based on observed characteristics. Mine-like objects are then investigated and, if necessary, neutralized by deploying the SLQ-60 SeaFox UUV.

SeaFox is a remote-controlled mini submarine drone that can be piloted to a mine while the ship remains at a safe distance. Using sonar, cameras, fiber optics and searchlights, SeaFox allows MCMs to gain valuable visual information of the ocean floor and identify mines with certainty without deploying divers into a minefield. SeaFox has different variants that allow it to be used for investigations, training or mine neutralization. The SeaFox used for mine neutralization is an explosive variant called a combat round or “C-round,” and is rarely used for training.

“You can’t recover a C-round once it’s been deployed; you have to send another C-round after it and blow it up if it malfunctions,” said Mineman 3rd Class Matthew Drees, of Lee, Massachusetts, who piloted a C-round into the inert MK 36 training mine. “The three years I’ve been in the Navy I’ve never heard of a C-round being used, so it was pretty cool putting all the training to practice.”

The explosion of the C-round shook the ship slightly upon detonation.

To assess the effectiveness of the C-round, Drees piloted a SeaFox investigative round to the training mine. Carefully reapproaching the training mine, Drees was able to visually confirm that the C-round’s directional charge collapsed the sensory data collection chamber that the MK 36 influence mine would use to arm itself. The C-round placed and detonated by Drees would have rendered a live mine inert.

Although the SeaFox pilot is ultimately responsible for putting the ordnance on target, they aren't the only person contributing to the work, said Heyworth.

"Every rating pulls their own weight in a small crew," he said. "It's a collaborative team effort that enables that pilot to accomplish the mission."

IMCMEX is focused on maritime security from the port of origin to the port of arrival and includes scenarios that range from mine countermeasures, infrastructure protection and maritime security operations in support of civilian shipping. The exercise, which includes international naval and civilian maritime forces from more than 30 nations spanning six continents training together across the Middle East, showcases the use of technology to protect freedom of navigation and free flow of maritime commerce.

Sentry is an Avenger-class Mine- Countermeasures ship homeported in Manama, Bahrain. Surface Warfare Magazine


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