About 300 yards out from the Fort Story beach, three old trucks or cars had been dumped. On the stern of the 511 Engineer Dive Detachment’s new 26-foot boat, Sgt. Kyle Ferguson was peering at the cloudy brown and yellow display on his computer, trying to spot them.
“We’re good, on the track,” Sgt. Carlos Ortiz, at the wheel, called back.
“What’s your depth? Ferguson replied, still peering at the screen.
“5-9,” Ortiz replied — 59 feet.
“Keep dropping it a little more,” Ferguson said to Staff Sgt. Ricardo Mansilla, who was keeping a tight grip on the 60-pound “tow-fish” — the torpedo-shaped side-scan sonar device the 511 soldiers were towing, as they drilled with the familiar chore of an underwater search but from a new boat.
The 26-footer is a big step up from the seven-person inflatable rafts the Fort Eustis-based detachment had been using for its underwater searches and for its main dive platform – there’s not much room on them for soldiers and the tow-fish and diving gear. But it means getting a feel for the bigger boat and how it moves through the water.
“Hey Ortiz, on this pass, head down a just a little farther,” Ferguson called. “With this current, I think they may have drifted down a little.”
Ferguson’s read on the current came after listening to how Ortiz had to goose the boat’s two big outboard motors when heading west, but kept them barely turning over when making a eastward pass.
The 511’s three-day exercise at Fort Story was a chance for the engineer-divers to drill on the underwater searches and underwater mapping that are just one part of their mission.
For mapping, they use a hydrographic survey depth finder — a long yellow rod, with a radio at one end and a sonar transceiver at the other.
Every few seconds, the radio pings a GPS ground station the soldiers set up on the first day of the exercise exercise while the sonar does the same for the seabed below — the result is a precise read on the depth at a precise location.
That’s what one of the 511’s newest soldiers, PFC Brian Warren, was working on in one of the seven-soldier rafts. He’d missed the class on the survey gear a few days earlier, in order to get a COVID-19 vaccination, but had been watching closely as Sgt. Caleb Blaylock programmed the equipment and was about to try for himself.
On the raft, the soldiers simply hold the depth-finder at the stern — but that’s not easy on their new boat, since the two big motors and the thick metal fender around them make things awkward. So Blaylock welded together a bracket to hold the depth-finder on the side of the new boat.
Later, Warren will get his turn on the new boat, working with the tow-fish and the side-scan sonar, searching for the submerged trucks.
When the 511 find them, comes the best part of their mission: “Diving!”, said Capt. Olivia Schretzman, the 511’s commander.
The 25-soldier detachment is a mix of old hands and soldiers, like Warren, fresh out of dive school. Much of the unit’s continuing training and drilling comes down to the old hands showing newer soldiers the ropes, Schretzman said.
“There’s always something new to learn,” she said. “I learn from them too.”
On the beach behind her, Sgt. Wesley Wray is running a class on chart-reader — but it’s a new subject for him.
“Ortiz has been on boats forever,” he said. “He talked to me a bit, gave me the books, and told me to study them,” he said.
“We’ve got GPS on the boats,” he said. “But if that blows up, we need to know how to get home.”
For Ortiz, meanwhile, the bigger boat isn’t that big a challenge.
“I’ve been out sailing with my dad since I was 4 years old,” he said.
But the new boat meant Mansilla’s task this day is a bit simpler — the inflatable bounces over waves in a way that keeps the tow-fish minder constantly hauling or easing up on the line to keep the fish at a relatively constant depth.
And with the fish not on the move quite as much, it’s easier for Mansilla and Ferguson to find the right depth to avoid the underwater clouds of sand that obscure sonar signals.
“Let’s try dropping it down another 15,” Ferguson asks Mansilla.
Then, frowning at the yellow cloud displayed on his screen, to the left of where it shows the boat’s track, Ferguson asks: “let’s drop another 10.”
Still frowning, he asks: “Bring it up a bit.”
The black line Mansilla hauls on is trembling below his grip as he hauls away.
“Try another 5,” Ferguson said.
“Yes, That’s a little better.”
Dave Ress, 757-247-4535, dress@dailypress.com
