Survivor tells of loss of power.
Three missing oil workers feared dead after helicopter carrying 18 ditched at sea - Telegraph
"Fifteen men, including eight described as walking wounded, were rescued following the incident close to Sumburgh Airport.
Dr Michael Bull, a father of one of the men rescued, said his son told him the helicopter lost power suddenly and immediately ditched into the sea. He said they "had seconds" before the craft hit the water, and then turned over."