HMCS Protecteur, a 44-year-old supply ship, was in the Pacific Ocean, north of Hawaii, on Thursday night when the fire broke out. The ship was on its way to its home port of Esquimalt, B.C.
The crew put out the flames and the ship was stabilized, though it had limited power, said Commodore Bob Auchterlonie, the commander of the navy's Pacific fleet.
Auchterlonie called the fire a "serious event," noting the large engine room contained a lot of fuel.
"Picture an elementary school gymnasium — three stories high, made of medal with a lot of machinery inside of that — and that space was on fire," he said Friday at Canadian Forces Base Esquimalt, west of Victoria.
"This was a worst-case scenario, a major machinery space fire, hundreds of miles from anywhere, and this ship defended itself on its own."
Auchterlonie commended the crew, who he said battled the fire over a significant period of time and saved the vessel.
He said roughly 20 people suffered minor injuries while fighting the blaze.
"There was dehydration, there was exhaustion, there was smoke inhalation, and that's what the nature of the injuries were," he said.
"Fortunately, we have a doctor on board, we have physician assistance on board, and we're aware all these people have been treated."
Auchterlonie said the fire extensively damaged the machinery that controls the vessel's propulsion, forcing the ship to stop in the water about 630 kilometres north of Hawaii.
"At this point, it's looking like she will be towed back to Hawaii, into Pearl Harbour," Auchterlonie said.
The American destroyer USS Michael Murphy and another ship were sent to assist the Canadian vessel, and Auchterlonie said the navy was also looking at the possibility of using Hawaii-based tugboats.
The commander said it wasn't clear when Protecteur would reach Hawaii, but technicians were heading to Pearl Harbour to meet it.
Protecteur is one of two auxiliary oil replenishment ships in the Canadian navy, both launched in 1969.
The crew on the 172-metre vessel contacted headquarters at CFB Esquimalt at 10:20 p.m. Pacific time on Thursday to report the fire, the navy said.
Auchterlonie said on Friday it was too early to speculate on the cause of the blaze, or how the incident would affect the navy's fleet of supply ships.
Protecteur, which left on Jan. 6 with HMCS Regina, was carrying 279 crew, 17 family members and two civilian contractors. The vessel was returning to B.C. from extended operations with the U.S. navy in the mid-Pacific.
The Department of National Defence said in a news release that having family members on board for the final part of such a voyage is a common practice with navy ships returning from extended operations and exercises.
"The idea behind it is they're seeing what life is like in a ship," Auchterlonie said. "Last night, they experienced more life on a ship than they probably wanted to experience again."
The aging Protecteur was damaged last August in a collision with HMCS Algonquin while en route to Hawaii.
Algonquin sustained the most significant damage in the accident, but Protecteur also suffered damage to its front end. Both ships were forced to cancel a planned voyage to Australia and instead return to port in Esquimalt for repairs.
The military announced in October that HMCS Protecteur and its sister ship on the East Coast, HMCS Preserver, will be retired in 2015.
Construction of new supply ships are expected to begin in late 2016, with a target of having them in service by 2019-20.
— By Vivian Luk in Vancouver
Follow @vivluk on Twitter
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