San Clemente Island

After being stuck almost 10 hours in an undersea vehicle ensnared beneath 1,270 feet of water, three Navy crew members freed their submersible Turtle at 1:30 a.m. Wednesday.

The Turtle was operating in Wilson Cove near San Clemente Island when it was caught in a Kevlar or plastic line Tuesday at 4 p.m. Officials said they are not yet sure whether the line, commonly used for mooring, belonged to a Navy or civilian vessel.

The crew, Lt. Cmdr. George Billy, Chief Petty Officer Kent Weekly and Petty Officer 2nd Class David Diepenhorst, had already been aboard the Turtle for eight hours when it was snared. The men suffered no ill effect from their prolonged underwater stay, said Lt. Sonja Hedley, spokeswoman for Submarine Group 5.

The Turtle is an underwater work vehicle used for research and recovery of submerged equipment, such as downed airplanes. It can remain underwater 80 hours and, at the time it was snared, it had 72 hours left.

The Turtle crew notified its support vessel, and the three-man crew freed the Turtle using an underwater robot camera that relayed pictures showing how the vessel was snared to the support ship, which then gave instructions for coming free of the line. The crew of the Turtle can only see forward.

When the Turtle was snared it was placing hydrophones, which are sonar listening devices.