Kneeling in the sand beneath 120 feet of water, the ship where his grandfather nearly perished 69 years ago looming before him, James Eric Tidwell made an impromptu tribute.

"I kind of laid my hands on it," said Tidwell, who had long hoped to dive the wreckage of the USS Jacob Jones while the man he calls "Gramps" is still alive.

Last weekend, the 39-year-old Navy commander was finally able to realize what he called this "awesome opportunity."

His grandfather, Joe Tidwell, 91, wasn't there for Friday's dive, but he did arrive from Florida on Sunday. He had not set eyes on Cape May since a Nazi U-boat torpedoed his Camden-built destroyer, killing 131 of the 142 men aboard.

It was Feb. 27, 1942, he was 21, and "that water was cold," Joe said, in a voice like Alabama, where he grew up.

If he hadn't gone to the galley to get sugar for the coffee for his crew in the boiler room when the torpedo hit, Joe Tidwell likely would have died with the rest. But he was a good swimmer, and he managed to get to a raft where he and 10 others were picked up.

On Sunday, Jim Rodan was on hand to welcome Joe to Cape May - for a second time.

An 87-year-old Navy veteran from Lower Township, he had met the Jones survivors in a local diner after they were pulled from the icy Atlantic.

"You probably don't remember me," Rodan said with a smile, shaking hands with Tidwell, then doing it again for the cameras.

Watching these two old salts - Tidwell in a wheelchair, Rodan leaning on a cane - was among a succession of emotional moments Sunday.

Volunteers organized by Atlantic Divers, which coordinated the Jones dive for free, joined the Tidwells and other veterans at the restored World War II lookout tower. As the weather turned from steamy to rainy, the gathering became a celebration of family, history, and country.

"This is epic," said Gene Peterson, the owner of the Egg Harbor Township firm.

"The dive went like clockwork. We had a great team."

Peterson supervised a deep-water training session for James Eric Tidwell at a quarry near Lancaster.

On Friday, they departed from Utch's Marina on Brian Sullivan's 36-foot boat, the RV Explorer. It took two hours to reach the Jacob Jones, and with Peterson acting as his diving tour guide, Tidwell was able to spend 22 minutes exploring the wreck.

The experience "was one of the most patriotic things of my life," Peterson said.

All three of Tidwell's children - Janet, with whom he lives, Joe, and Jim [James' father] flew from Florida, Arizona, and Tennessee.

Standing proudly around their father's wheelchair, they said he taught at a Jacksonville vocational high school for many years after his career in the Navy.

The family has a long tradition of military service; Joe's two brothers also fought in World War II, and since then there has always been a Tidwell in uniform.

But Joe rarely talked about the war; only when his wife, Jeanette, died two years ago ("She was my sweetheart," Joe said) did his children find a cache of clippings and other material about the Jacob Jones.

His grandson said that while he had thought about doing the dive for several years, that his next command will be with a flight squadron based in Japan added to the urgency.

"For me to be able to do it," he said, "was an honor."

Contact staff writer Kevin Riordan at 856-779-3845, kriordan@phillynews.com, or @inqkriordan on Twitter. Read the metro columnists' blog, "Blinq," at http://www.philly.com/blinq.