Early morning of the 21st of February 1917, the SS Mendi slowly steamed ahead in the thick fog through the English Channel, constantly blowing her whistle. Her escort, the destroyer HMS Brisk, following her stern light. The thick fog reduced visibility to almost nothing. As the Mendi made her way to La Havre in France to unload her labour troops from South Africa, the SS Darro, sounding no whistle, suddenly appeared on her starboard bow and seconds later crashed into her with full speed at almost right angle, instantly killing the men in the forward holds.

The two ships spun around and eventually drifted apart. Those men who did not die on impact, drowned in the dark icy English Channel waters. The SS Mendi rapidly began to sink. Men rushed to their designated points on the deck to launch the lifeboats, but the Mendi listed heavily to starboard, rendering the port side lifeboats ineffective. Officers and NCO's urged the men to jump into the water and get away from the sinking ship.

With only a few of the boats in the water, other men hung onto the life-rafts and life-buoys in the just above freezing waters. Skin colour didn't matter anymore, just humanity. Men were men, saving each other from the dangers of the deep. Several men gave up their seats to accommodate others. They sang and prayed together. 

As the men tried to survive in the water, HMS Brisk quickly sent out boats to help the men, but it was difficult in the thick fog. On the other hand, the master of the SS Darro, Captain Stump made no attempt to investigate any possible survivors in the water. Only when a life boat rowed up to the Darro did the men realise that there are men in the water, yet Stump still did not send out boats to rescue the survivors, even though the SS Darro was in no danger after the collision and had more than enough life saving equipment on board.

Only the few survivors were picked up by the SS Darro, the others were picked up by the HMS Brisk and Sandsend. In total 647 men were missing, under the water or dead in lifebelts. Of the South African Native Labour Contingent, 607 of 802 died. 2 of their 5 officers, and 7 of their 17 NCO's. Of the crew 89 of the SS Mendi, 31 died.

An avoidable accident if the SS Darro followed the regulations set by the Board of Trade, by maintaining slow speed and sounding her whistle. After a formal hearing and investigation, Stump was suspended for a year as he was negligent in following the regulations. The court came to the conclusion that he simply lost his nerve, for not saving any of the men.