PORTLAND – The lifeboat accident that took the life of a Canadian oil rig worker came without warning and was over in an instant, one of the two survivors said.

Kevin Nicholson said Tuesday he was sitting in the back of the 26-foot enclosed lifeboat Jan. 13 as it was being hoisted back to the deck of the newly built rig Pride Rio de Janeiro at the end of a demonstration drill.

“There was [a] large, loud boom and something let go. I really couldn’t say what it was,” Nicholson told the Portland Press Herald on Tuesday.

Nicholson and two co-workers were inside the bright orange lifeboat when it disconnected from its cables and plunged about 60 feet into the water.

Andrew Caldwell, 49, of Atlanta, Nova Scotia, was killed when the boat hit the water. Charles Dorey of Cape Breton, Nova Scotia, was hospitalized for several days and has declined to talk to the media about the accident.

Nicholson, now home in Halifax recovering from a broken wrist, said he feels lucky to be alive.

The Maine Medical Examiner’s Office said Tuesday that Caldwell died of massive head and neck trauma.

The three men had been in Portland a few weeks as part of a crew working and living aboard the rig, which was outfitted by Cianbro Corp.

The accident occurred when a cable had somehow disconnected from the hook at the rear of the boat, leaving only the cable at the front attached.

“The boat started to drop out from underneath me and there was another loud ‘kaboom’ when the other end let go,” Nicholson said. “And then there was that falling sensation.”

He said he felt weightless and knew they were falling before the roof of the boat struck the water with a “a big splat” that caved in the fiberglass shell.

“Immediately, the water rushed in,” he said.

Nicholson said he was not strapped in and is not sure how he escaped more severe injury when the boat struck the water. He and Dorey were able to get out of the boat into the water, where help was already arriving.

U.S. Coast Guard investigators continue to search for the cause of the accident. There were no obvious mechanical failures or human errors that provided an easy explanation, and manufacturers are helping examine the hook system that is supposed to secure the boat to the cables.