The official explanation for the Estonia accident was that the bow gate failed, but rumors say the real cause was nuclear waste smuggled from Russia to the west spilled onto the car deck from the trailer of a Russian truck. The nuclear waste quickly corroded the already rusted bow visor, and masses of water rushed onto the car deck. Unfortunately, at the same time, the ship's crew opened the stern gate to vent cigarette smoke from the car deck. The cargo began to move, and this caused the list that caused the ship to sink. Signs of an accident were already in the air shortly after leaving Tallinn, when the Estonia steamed at full speed in 25 meters per second winds and a storm to demonstrate its superiority over the ships of Viking Line and Silja. In early 2017,
Risumies gave an interview to Yle's Friday program, in which he shared his own view of the accident and its cause: "The Estonia wouldn't have drowned if it had stayed on the shore!"
Hikipedia