One day in early February this year, Viking Line's Rosella passenger ferry left port from Mariehamn, Åland with its bow door open. The Åland Shipping Association says that the ship's crew tried unsuccessfully to close the visor.
The hydraulic locking system wasn't working properly, but the ship set sail towards Sweden on schedule. As the cruise began, the ship's crew consulted Viking's technical director.
Together, they agreed that if they weren't able to close the door once the boat reached a lighthouse, some 7 kilometres from port, they'd turn back to port.
However, the traffic safety administration says that Rosella had already passed the lighthouse and sailed into open waters before the bow door was secured.
Wind speeds that day were reported to be 15 metres per second with rough seas. Viking said that there are other watertight doors installed in the bow, as became mandatory after the Estonia tragedy, and that these doors were working properly.
Viking's technical director Tony Öhman said that whether the Rosella incident was illegal remains up for discussion.
Traffic safety officials are investigating the incident. The Agency's maritime inspector said that regulations on the locking of bow doors are clear.
International Laws on locking ferry bow doors changed some 20 years ago. It was the cruise ship Estonia tragedy in 1994 that sparked those changes.
The Estonia's bow door was left unsecured before water flooded car decks causing the ship to sink to the bottom of the Baltic and claiming 757 lives.