As Alvarez tries to secure the exposed mooring chain to a pulley, the ship's movement causes the big links to slide across the deck toward him. Young pulls his shipmate quickly out of harm's way by his life jacket. No one is hurt.
The buoy is encrusted with more than 3,000 pounds of mussels, urchins and starfish that fill the air with a strong briny odor. The growth, more than a foot thick in places, is removed with scrapers and high-pressure hoses, scattering slippery organic debris throughout the work area.
By now, the buoy deck is filled with a cacophony of sledgehammers, clanking chain, pneumatic wrenches and a whining power saw used to cut open master links that connect lengths of mooring chain. Orange sparks rain across the deck.
"I love it," said Chief Warrant Officer Dan Twomey, the Cobb's executive officer, who has worked on buoy tenders for half of his 14-year career. "As an enlisted man, I got out of it for a while, but when the opportunity arose again, I took it."
Twomey is on the port side of the bridge, two decks above the buoy.
He keeps the Cobb in position with the help of global positioning satellites, computers and a small joystick connected to one of the most sophisticated propulsion systems available--Z-Drive.
The Cobb, which went into service two years ago, has no rudder. Instead, it is equipped with bow thrusters and two aft propellers that can pivot. The ship can move sideways or rotate 360 degrees, ideal for buoy tending.
That kind of maneuverability was unheard of aboard the aging Conifer, a World War II-era buoy tender that the Cobb replaced.
The Conifer had a crew of 50 compared to the Cobb's 24, and the vintage ship took much longer to perform some of the same tasks.
The Cobb's navigation systems are so accurate it can reset a buoy within three meters of the spot where it was removed.
"It used to take one or two hours to get back on station by manual triangulation," Twomey said. "It was a real challenge."
On deck, the crew replaces 90 feet of the light buoy's mooring chain with a technique they have dubbed "heat and beat." The pin of the new master link is heated with a blow torch until red hot.
Then Young and Morfin take turns smashing the softened steel with sledgehammers. They look like a pair of railroad workers driving spikes.
After the electrical system and batteries are tested, Lighted Bell Buoy No. 1 is ready to be lowered back into the sea.
The crane operator puts tension on the line and the lashings are removed.
"Live buoy!" Cavallo yells. "Stand clear."
The crane operator slowly lifts the navigation aid slightly off the deck and eases it over the port side into the water. All lines and tackle are removed before the Cobb backs away.
"Buoy's clear," Cavallo says. "Good job this time. Good job."