01:09 - Source: CNN
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Inactive nuclear bomb reportedly found in Canada

Plane carrying dummy nuke went down over British Columbia in 1950

CNN  — 

A diver hunting sea cucumbers may have found a missing inactive nuclear device – which some historians have dubbed “the lost nuke” – jettisoned by a US bomber in 1950.

Canadian coastal defense forces will investigate water around Prince Rupert, in British Columbia, after diver Sean Smyrichinsky found a mysterious object on a recent trip, officials told CNN.

“I came out from the dive and I came up and I started telling my crew, ‘My god, I found a UFO. I found the strangest thing I’d ever seen’,” Smyrichinsky told the CBC, a CNN partner broadcaster.

After friends told him of a B-36 bomber that crashed in 1950 with a Mark IV nuclear weapon on board, he looked up photos of the bomb online.

“It was a piece that looked very much like what I saw,” he told the broadcaster. “The plane that was carrying the bomb, it crashed 50 miles south of where I found that object.”


On February 13, 1950, a Convair B-36B plane was flying from Alaska to Texas when something went wrong.

“One engine is feathered, and two others are losing power. We are descending,” the crew radioed, according to Robert Dorr’s history of the bomber group.

“Severe emergency (…) letting down due to icing and an engine fire. Alerted crew to bail out but may ditch.”

The missing Mark IV bomb is a modified form of the "Fat Man" detonated over Nagasaki in 1945.

At 8,000 feet, before the 17 crew members parachuted out of the doomed plane, they jettisoned a dummy nuclear bomb they were carrying on board.

The bomb – a Mark IV nuclear weapon filled with lead, uranium and TNT, but not the plutonium necessary for a nuclear explosion – has been missing ever since.

A US Army Air Force B-36 bomber.


In a statement, Canada’s Department of National Defense said the device Smyrichinsky found did appear to be the dummy B4 weapon.

“That particular dummy capsule did not contain any nuclear material and there is no suspected radiological safety hazard from this ordnance,” it said.

HMCS Yellowknife will investigate the area in coming weeks, and a submersible will take photos and video of the ocean floor to finally say for sure, if the missing device has been found.