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Two ships collide and Halifax reels

The Story

On a beautiful December morning, the Mont-Blanc sails towards Halifax Harbour as re-enacted in this CBC Television clip. The French munitions ship is about to join a cross-Atlantic convoy to Europe and the war effort. On the other side of the harbour, the Norwegian ship Imo is on its way out of the harbour, heading to New York to pick up relief supplies for Belgian civilians. The Imo is running behind schedule. Amidst the rush and port traffic, the Imo crashes into the starboard side of the Mont-Blanc shortly before 9 a.m. Collisions are not uncommon at the time, especially given the heavy wartime traffic. But on that Thursday the Mont-Blanc is carrying 2,600 tons of military explosives. It is a floating bomb but in order to avoid German U-boat attacks the Mont-Blanc isn't flying warning flags. When the two ships pull away, the collision starts a fire on the Mont-Blanc's deck. The fire quickly ignites the dangerous cargo on board. At precisely 9:04:35 on Dec. 6, 1917, the Mont-Blanc explodes with a force the world has never known. 

Medium: Television
Program: CBC Television Special
Broadcast Date: May 24, 1967
Host: Thomas Raddall
Duration: 4:27

Did You know?

• At the time of the explosion, the Mont-Blanc was carrying 226,797 kg of TNT, 2,146,830 kg of picric acid, 56,301 kg of guncotton and 223,188 kg of Benzol -- all highly explosive and dangerous chemicals.

• The starboard side refers to the right-hand side of the ship when facing the bow(front).

• The Halifax explosion was the greatest man-made explosion in history until the atomic bomb in 1945. The 1917 explosion was 1/7 the size of the bomb dropped on Hiroshima.

• Physicist Robert Oppenheimer, known as the "father of the atomic bomb," studied the Halifax explosion to calculate the strength of the bombs that would be dropped on Hiroshima and Nagasaki.


The Halifax Explosion more