The adventurous life of a fast-rising Pearl Harbor Navy officer came to a tragic end May 20 when he may have encountered problems using a complex “rebreather” device in the early stage of an off-duty dive off Waikiki.

Ensign Brian Bugge, 35, leaves behind children ages 2 and 3. His widow, Ashley, is seven months pregnant.

“Brian and I at least once or twice a week for the past five years have said, ‘How the hell did we get so lucky with each other?’” Ashley Bugge said. “I don’t know what life looks like now.”

A GoFundMe page to help the family has been set up at www.gofundme.com/brian-bugge-memorial.

Brian Bugge, who served on the submarines USS Ohio and USS Pennsylvania, made the rank of chief petty officer in 10 years.

Even though he didn’t have a college degree, he was promoted three years later to ensign limited-­duty officer, his widow said. In Hawaii he was assigned to the U.S. Pacific Fleet Submarine Force’s Integrated Undersea Surveillance Systems department as the training and assessments officer.

“Brian was the best of the best of the best. He pushed himself in every possible way,” Ashley Bugge, 34, told the Honolulu Star-Advertiser in a phone interview.

He had COURAGE tattooed in big letters down one shin, and STRENGTH on the other.

The couple bought a 36-foot sailboat in Washington state, and then Brian Bugge learned he would be moved to Hawaii. He sailed the Stay Gold here from Gig Harbor with his cousin and two friends, leaving July 6 and arriving 21 days later.

He had served in Africa, was an avid underwater photographer and recently had signed up for a cave diving course in Florida.

“His priorities in life, without a doubt, were me and our children, and below that was adventure in any type and form — as long as it was on the water, sailing, diving and being on submarines,” Ashley Bugge said.

The next step in diving for Brian Bugge was the use of a rebreather, a closed-circuit system that absorbs carbon dioxide, recycles oxygen and adds more oxygen.

Rebreathers allow divers to go deeper and stay down longer — and don’t emit bubbles like scuba tanks, which makes them appealing to special-operations divers.

“We’re both open-water scuba certified, but he was really interested in the challenge and the technical side of the rebreathing,” Ashley Bugge said. She added that “his thing was, What can I do next? What’s bigger and better?”

Andrew Fock, then with the Department of Intensive Care and Hyperbaric Medicine at The Alfred Hospital in Victoria, Australia, wrote a research paper in 2013 that said rebreathers have a 25-fold increased risk of component failure compared with scuba.

KISS Rebreather in Arizona, which sells the devices, even warns on its website that rebreather diving “can result in serious injury or death.” The devices have hundreds of parts — “which will eventually fail,” KISS said.

“Careful maintenance, assembly and testing will not prevent a failure from happening. At best it will only delay the failure,” the company said.

Use of a rebreather requires constant monitoring and a complete awareness of potential problems likely to be encountered, KISS said.

Scuba Diver Life reported in 2017 that Canadian filmmaker Rob Stewart was diving to 229 feet on a rebreather with another diver in the Florida Keys.

Both hit the surface with breathing problems, and while the other diver was attended to, Stewart suffered hypoxia, or lack of oxygen, blacked out and sank, the publication said. His body was found days later at 300 feet.

Brian Bugge was planning to dive on the Sea Tiger, a well-known wreck in about 90 to 110 feet of water, using his own rebreather equipment.

The Navy man was the first in the water and had headed over to the dive line, where someone handed him his camera, Ashley Bugge said.

“(Brian) was communicating with them, and then the next person got in the water and went to check the visibility,” she said. In that first minute or so, something happened, and her husband was spotted 30 to 40 feet underwater with the rebreather “loop” air piece out of his mouth, Bugge said.

Another diver managed to get Brian Bugge to the surface, but more minutes had passed, she said. Cardiopulmonary resuscitation and mouth-to-mouth breathing was started. He was transferred to a hospital where he died, officials said.

The Honolulu Police Department is investigating, and autopsy results haven’t been released yet, Ashley Bugge and officials said. A “first look” by the medical examiner’s office didn’t find any trauma that could cause a blackout. The Navy ensign had about 100 hours on the rebreather, “which is a lot of hours,” she said.

The family is now taking things one day at a time, and made it through the funeral with a gun salute and folded-flag presentation, Bugge said.

She and her kids plan to leave by the end of the month for Boise, Idaho, where her husband’s family lives and where she plans to have her baby.

“At this point, throughout the day I have moments where I’m waiting to wake up from this terrible pregnancy dream,” she said.

“Ensign Bugge’s drowning was certainly a loss to the Navy and the submarine force. Our sincerest condolences, prayers and support have been provided to his family and friends,” said Cmdr. Corey Barker, a spokesman for the Pacific submarine force.

Ashley Bugge plans to scatter some of her husband’s ashes in Puget Sound in Washington, where they are from.

“And then I think next year — I say this now but I don’t know how I’ll be feeling a year from now,” she said, “I’d like to come back here and take a boat out and scatter (his ashes) over the Sea Tiger where he went down.”